Sorting method using actively controlled magnetic microparticles

Abstract

Disclosed is a magnetic sorting method for selectively separating biological target particles (142) from other biological particles (146) within a liquid of a suspension (160). The method comprises providing the suspension (160), which is added with magnetic microparticles (140). At least a shell section (170) of each of the magnetic microparticles (140) is applied with target-specific surface coupling elements (190) configured for selectively coupling to a surface of the biological target particles (142). A dynamic magnetic field is applied for actively controlling movements of the magnetic microparticles (140) within the suspension (160) and coupling to the biological target particles (142) via the target-specific surface coupling elements (190) forming magnetic particle complexes (144). The magnetic particle complexes (144) are separated from the other biological particles (146) using a magnetic moment of the magnetic microparticles (140) comprised by the magnetic particle complexes (144).

Description

SORTING METHOD USING ACTIVELY CONTROLLED MAGNETIC MICROPARTICLESFIELD OF THE INVENTION

[0001] The invention relates to the field of biological sorting, more precisely a selecting and separating of biological target particles.BACKGROUND

[0002] Biological sorting, i.e., a selecting and separating of biological target particles, may be required for a wide range of applications. However, it may be challenging to provide an efficient and effective sorting method. In particular, providing a sorting method which works for a wide variety of biological target particles may be challenging.SUMMARY OF THE INVENTION

[0003] It is an objective to provide for a magnetic sorting method for selectively separating biological target particles from other biological particles within a liquid of a suspension. It is a further objective to provide for a computer program and a computer component for controlling a magnetic sorting system for selectively separating biological target particles from other biological particles within a liquid of a suspension. Finally, it is an objective to provide for a magnetic sorting system for selectively separating biological target particles from other biological particles within a liquid of a suspension. The objectives underlying the invention are solved by the features of the independent claims.

[0004] Disclosed is a magnetic sorting method for selectively separating biological target particles from other biological particles within a liquid of a suspension. The method comprises providing the suspension. The suspension is added with magnetic microparticles, which comprise a permanent net magnetic moment. At least a shell section of each of the magnetic microparticles is applied with target-specific surface coupling elements configured for selectively coupling to a surface of the biological target particles. A dynamic magnetic field is applied for actively controlling movements of the magnetic microparticles within the suspension. Theapplied dynamic magnetic field is configured for inducing the magnetic microparticles to perform translational movements through the suspension and, while moving through the suspension, to couple to the biological target particles via the target-specific surface coupling elements forming magnetic particle complexes. The magnetic particle complexes are separated from the other biological particles using the magnetic moment of the magnetic microparticles comprised by the magnetic particle complexes.

[0005] Examples may provide a method for selectively targeting biological target particles and separating the biological target particles from other biological particles within a liquid of a suspension using actively controlled translational movements of magnetic microparticles. The active controlling of the translational movements of magnetic microparticles may, e.g., comprise a spatial and / or a temporal controlling. For example, the active controlling may comprise a spatiotemporal controlling. Thereby, the active controlling of the translational movements may allow for a globally controlling and / or timing of positions of the magnetic microparticles within the suspension. For example, positions of the magnetic microparticles on a surface of a substrate may be controlled and / or timed.

[0006] Examples may use the actively controlled translational movements of the magnetic microparticles to select and separate biological target particles. Examples could have the advantage that an enhanced effectiveness in targeting and separating target biological particles may be achieved. This may result from an enhanced effectiveness of the coupling to the biological target particles enabled by the usage of the dynamic magnetic field for actively controlling the translational movements of the magnetic microparticles. By controlling the movements of the magnetic microparticles, their interactions with the biological target particles may be controlled. Furthermore, an enhanced coupling efficiency may allow for an enhanced separation efficiency using the magnetic moment of the magnetic microparticles comprised by the magnetic particle complexes.

[0007] Examples may provide a method for separating biological target particles, such as cells, biomolecules, and / or DNA, from other biological particles using actively controlled translational movements of magnetic microparticles. The magnetic microparticles may, e.g., be moved over a surface of a substrate.

[0008] The target-specific surface coupling elements conjugated to the actively controlled magnetic microparticles may enable a selective coupling of the magnetic microparticles tobiological target particles. Such target-specific surface coupling elements may, e.g., comprise recognition moieties, like antibodies, peptides, and / or small molecules.

[0009] The actively controlled translational movements of magnetic microparticles may enhance a binding efficiency of the magnetic microparticles to the biological target particles and accelerating the selection as well as the separation.

[0010] Biological sorting refers to a selectively targeting and separating of desired biological target particles and may be used for various applications. Examples may provide for a magnetic sorting using magnetic microparticles that are coupled to the biological target particles using target-specific surface coupling elements, like specific targeting moieties. The magnetic microparticles may be used for labeling the biological target particles. The biological target particles labelled with the magnetic microparticles, i.e., the resulting magnetic particle complexes, may then be separated using the magnetic moment of the magnetic microparticles. For example, magnetic field gradients may be used for moving and / or retaining the magnetic particle complexes for the purpose of separation.

[0011] Examples may provide a novel method for sorting biological materials, i.e., biological target particles, like cells and proteins, using actively controlled magnetic microparticles, which are actuated using a dynamic magnetic field. This active control using the dynamic magnetic field may enable the magnetic microparticles to locate and collect the biological target particles within a suspension. For example, the biological target particles may be located and collected within a microfluidic chip, cartridge, Petri dish, or similar environment. Upon recognizing the biological target particles, e.g., through surface interactions, magnetic particle complexes may be formed and transferred to a target region for sorting and / or additional downstream analyses. Examples may overcome the limitations of passive particle movements within the liquid of the suspension. Thereby, a safe and thorough mixing of the magnetic microparticles with the biological particles comprised by the suspension and in particular with the biological target particles may be achieved. This may, e.g., significantly improve an overall accuracy, shorten a required time for executing the sorting method and improve reliability of the sorting method.

[0012] Examples may enable actively controlled translational movements of the magnetic microparticles throughout the complete suspension, e.g., in a dispersed and homogeneous manner. Examples may enable actively controlled translational movements of the magnetic microparticles over a comparably large area. For example, actively controlled translational movements over a substrate of a 100 mm Petri dish may be enabled with magneticmicroparticles moving from one boundary to the other over the whole substrate. The actively controlled translational movements of the magnetic microparticles through the complete suspension may significantly increase a likelihood of collisions between the magnetic microparticles and the biological target particles throughout the suspension leading to a reduction in selection and separation time. For example, the selection and separation time may, e.g., be reduced to just a few minutes.

[0013] Magnetic field properties of the dynamic magnetic field may be configured to ensure that the magnetic microparticles travel over and cover the entire area of the suspension, e.g., an area on which the suspension spreads over a surface of a substrate. Thus, the magnetic microparticles may be enabled to quickly encounter the biological target particles on their way through the suspension. As a result, an efficiency of targeting and sorting of the biological target particles may be increased.

[0014] Examples may be capable of handling a wide range of starting biological material volumes, i.e., numbers of biological particles. Small as well as large samples may be handled. For example, samples with particle numbers from 103to 107may be handled efficiently.

[0015] Examples may provide for an unsupervised, rapid sorting method for selectively separating biological target particles from other biological particles within a liquid of a suspension. Examples may allow for an automated sorting method, which may require minimal to no supervision. For example, micro- and conventional robotics may be leveraged to ensure an accurate sorting of the biological target particles with high efficiency and reliability.

[0016] Examples may offer potential advancements in diagnostics, disease monitoring, cell isolation and sorting, as well as medical research applications. Examples may be applicable in the fields of oncology, hematology, cell engineering and immunology.

[0017] The suspension may comprise a heterogeneous mixture of biological particles, i.e., the biological target particles as well as the other biological particles.

[0018] The dynamic magnetic field may be applied to actuate the magnetic particles, e.g., on a substrate, by breaking a flow-field symmetry for the magnetic particles within the liquid of the suspension. An orientation of the dynamic magnetic field may determine a direction of movement of the magnetic particles throughout the suspension. The dynamic magnetic field may, e.g., be generated using an electromagnetic coil configuration, rotating and / or translationally moving a permanent magnet and / or permanent magnet configuration. The sourceof the dynamic magnetic field may be arranged at a distance, where field gradients are negligible or insignificant. Implementing predefined, e.g., preprogrammed movements of the magnetic particles within the suspension, e.g., on a surface of a substrate, may increase the chance of collisions between magnetic particles and biological target particles. An increased chance of collision may go hand in hand with an increased chance of a coupling of the magnetic microparticles to the biological target particles.

[0019] Translational movements refer to directed movements of the magnetic microparticles, e.g., on a substrate. A velocity of the translational movements may be defined by body length or body diameter per time, e.g., body length per seconds (B.L. / s). The actively controlled translational movements of the magnetic microparticles using the dynamic magnetic field are achieved using a net magnetic moment m comprised by the individual magnetic microparticles. The dynamic magnetic field may induce symmetry-breaking movements of the magnetic microparticles, i.e., movements breaking a flow-field symmetry around the magnetic particles, which are then converted into translational movements of the magnetic microparticles. The translational movements of the magnetic microparticles may, e.g., comprise movements of the magnetic microparticles along a surface of a substrate, on which the suspension is arranged. Position of magnetic microparticles within the suspension may, e.g., be actively and precisely controlled by adjusting properties of the dynamic magnetic field.

[0020] The dynamic magnetic field may, e.g., be a magnetic field generated using an electromagnetic coil configuration comprising one or more magnetic coils, a permanent magnet configuration comprising one or more permanent magnets, or combinations thereof. A dynamic magnetic field may be a magnetic field characterized by time-varying and / or spatially varying properties. A dynamic magnetic field may, e.g., exhibit a temporal modulation and / or spatial modulation. A temporal modulation may, e.g., comprise an amplitude, a frequency, and / or a phase varying over time. A spatial modulation may, e.g., comprise a creation of one or more gradients, a shifting of a center of rotation of the magnetic field, and / or a reorientation of the magnetic field. Varying properties of a dynamic magnetic field may, e.g., change continuously and / or in discrete steps or intervals. An interaction of such varying properties may result in spatiotemporal changes, e.g., a combination of a temporal and a spatial modulation, in the magnetic field. A dynamic magnetic field may, e.g., be implemented as a rotating magnetic field, an oscillating magnetic field, a pulsed magnetic field, and / or a magnetic field comprising one or more magnetic field gradients. Such a dynamic magnetic field may be utilized to generate translational movements of the magnetic microparticles. For example, the dynamic magneticfield may be used for inducing rotations of the magnetic microparticles, which result in the translational movements. Properties of the dynamic magnetic field may be adjusted based on specific requirements to be satisfied by the translational movements of the magnetic microparticles, like speed, direction, and / or efficiency.

[0021] A rotating magnetic field is a specific type of dynamic magnetic field where a magnetic field vector of the magnetic field rotates, i.e., changes orientation continuously or discretely following a circular or elliptical path around a fixed or moving axis of rotation. Such a rotation of magnetic field vector may, e.g., be achieved using a rotation and / or translation of one or more permanent magnets of a permanent magnet configuration and / or of one or more electromagnets comprising an electromagnetic coil configuration with one or more electromagnetic coils. The rotation of magnetic field vector may, e.g., be achieved by applying multiple time-varying currents to a set of electromagnets, e.g., a set of electromagnetic coils, resulting in a net rotating effect. The generated rotating magnetic field may induce the translational movements of the magnetic microparticles. Direction, speed and / or efficiency of the translational movements may be adjustable using adjustments of properties of the dynamic magnetic field.

[0022] The selection and separation of the biological target particles using the magnetic sorting method may, e.g., involve forming complexes between the magnetic microparticles and the biological target particles. In case of a positive selection, the biological target particles may be biological particles of the suspension to be kept, while the other biological particles are biological particles to be removed from the suspension. In this case, a target of the selection and separation may be to remove the other biological particles. In case of a negative selection, the biological target particles may be biological particles to be removed from the suspension, while the other biological particles are biological particles of the suspension to be kept. In this case, a target of the selection and separation may be to remove the biological target particles.

[0023] The magnetic particle complexes may, e.g., be isolated using the actively controlled translational movements of the magnetic microparticles and / or magnetic field gradients. The isolation may, e.g., be followed by an extraction of the isolated magnetic particle complexes. The extraction may allow for a further usage of the extracted magnetic particle complexes and / or for a further usage of the remaining solution, from which the magnetic particle complexes have been extracted. The isolation may, e.g., be followed by a washing. By the washing, e.g., the other biological particles may be removed from the suspension. The removal may allow for a furtherusage of the removed biological particles and / or for a further usage of the retained magnetic particle complexes, while the other biological particles are removed.

[0024] In positive selection, the biological target particles may be particles to be magnetically labelled, in order to retain the labelled particles. In negative selection, the biological target particles may be particles to be magnetically labelled, in order to remove the labelled particles and leave the other biological particles in the suspension.

[0025] For the separating, e.g., magnetic field gradients may be used to selectively attract and retain the magnetic particles complexes formed by the magnetic microparticles coupled to the biological target particles. For example, the magnetic particles complexes may be retained on a surface of a substrate. These magnetic field gradients may, e.g., enable a targeted attachment of the magnetic particle complexes to the surface, ensuring their retention while the other biological particles may be efficiently extracted for further usage or while the other biological particles may be efficiently washed away as remnants to be discarded. A strength and / or configuration of the magnetic field gradients may be used for controlling an attachment process, e.g., in order to enhance a separation efficiency and / or facilitating a removal of uncoupled biological particles using a subsequent washing.

[0026] Examples may be adaptable for larger-scale processing by increasing a substrate size, e.g., using layered substrates, and / or integrating parallel magnetic field generator components. The resulting scalability may make the examples suitable for industrial-scale bioprocessing and / or environmental sample analysis applications.

[0027] Examples may enable a customizability of the dynamic magnetic field. For example, a tailoring of the dynamic magnetic field generated by the magnetic field generator component for unique applications may be enabled, such as a differentiating between closely related cell types by adjusting motion dynamics of the magnetic microparticles to favor specific interactions with biological target particles.

[0028] Examples may, e.g., be integrated with other separation methods, such as acoustic or dielectrophoretic separation systems, to provide hybrid systems capable of multi-modal sorting and analysis, e.g., increasing a utility in complex biological samples.

[0029] Examples may, e.g., apply the sorting method in a dynamic environment such as a microfluidic system. For such an application in a dynamic environment the interaction betweenfluid flow and magnetic microparticle movements may be adjusted to prevent an undesired drift and ensure effective substrate coverage.

[0030] Examples may integrate the magnetic sorting method with automated systems, e.g., robotic systems, enabling a fully automated, high-throughput setup. Such a setup may, e.g., further be integrated with imaging and / or analyzing tools for a real-time monitoring.

[0031] Examples may, e.g., allow for a usage of a low-energy magnetic actuation ensuring environmental sustainability, especially in large-scale and / or continuous operation scenarios, aligning with green technology principles.

[0032] Examples may, e.g., use a substrate with an adaptive surface with dynamic properties, such as switchable adhesion and / or a temperature-sensitive coating. A usage of such an adaptive surface may further refine the separation and isolation achievable by the magnetic sorting method.

[0033] Examples may, e.g., enable a single-cell sorting with high precision, enabling applications in single-cell genomics and proteomics. For achieving such a single-cell sorting with high precision, e.g., a particle size of the magnetic microparticle and / or an optimizing magnetic field control may be adjusted.

[0034] Examples may, e.g., be integrated with a remote system setup allowing for a remote operation of a magnetic sorting system. Examples may enable a remote monitoring and / or controlling of a magnetic sorting method, making the system suitable, e.g., for decentralized laboratory setups and / or fieldwork applications.

[0035] Examples may, e.g., enable a surface marker quantification. Examples may enable an isolating and enriching of specific cell populations. This feature could be coupled with a quantification technique to determine an abundance and / or distribution of specific surface markers, aiding in detailed phenotypic profiling.

[0036] Examples may, e.g., be integrated with a real-time analytical tool, like a spectrometry device and / or an on-chip PCR. Thus, an inline analysis of sorted samples may be enabled, reducing a need for separate downstream workflows.

[0037] Examples may allow for dynamic adjustments during sorting. A real-time monitoring of the sorting process may, e.g., allow for dynamic adjustments to magnetic field parameters to improve a performance of the magnetic sorting, e.g., in response to a sample variability.

[0038] In an example, the method further comprises retaining the magnetic particle complexes on a surface using a magnetic field gradient in a direction perpendicular to the surface.

[0039] Examples could have the advantage that a stable retention of the magnetic particle complexes and thus of the biological target particles could be achieved for a selective isolation of the complexes. This may be enabled by the magnetic field gradient spatially confining the magnetic particle complexes during separation.

[0040] In an example, the method further comprises using the dynamic magnetic field to move the magnetic particle complexes to a predefined target area of the suspension.

[0041] Examples could have the advantage that a precise localization of magnetic particle complexes and thus of the biological target particles could be achieved by directing the magnetic particle complexes to the predefined target area using the dynamic magnetic field. Thus, a targeted collection and localization of the biological target particles may be achieved.

[0042] In an example, the method further comprises extracting the magnetic particle complexes from the predefined target area within the suspension.

[0043] Examples could have the advantage that an efficient extraction of the magnetic particle complexes and thus of the biological target particles could be achieved. This extraction may, e.g., be facilitated by the concentration of the magnetic particle complexes with the biological target particles in the predefined target area. Examples could make it possible to enhance effectiveness and efficiency of the extraction by focusing the extraction to the predefined target area. For example, dispersion of the biological target particles within the suspension may be reduced by collecting the biological target particles within the predefined target area.

[0044] In an example, the method further comprises extracting the other biological particles from the suspension.

[0045] Examples could have the advantage that an effective separation may be achieved with only the magnetic particle complexes, which comprise the biological target particles, remaining. Examples could make it possible that a sample purity may be increased, resulting from the systematic removal of undesired particles from the suspension. The undesired particles may, e.g., be the other biological particles. The undesired particles may, e.g., be biological target particles.

[0046] For example, when retaining the magnetic particle complexes on a surface, the remaining suspension with the other biological particles may be pipetted. This may provide an easy and efficient method for extracting the other biological particles from the suspension.

[0047] For example, the dynamic magnetic field is a temporally varying magnetic field. For example, the dynamic magnetic field is a spatially varying magnetic field. For example, the dynamic magnetic field is a spatiotemporally varying field.

[0048] For example, the dynamic magnetic field comprises one or more of the following: a rotating magnetic field, an oscillating magnetic field, a pulsed magnetic field, a magnetic field gradient.

[0049] In an example, the dynamic magnetic field comprises a rotating magnetic field causing rotations of the magnetic microparticles. The rotations of the magnetic microparticles result in the translational movements of the magnetic microparticles.

[0050] Examples could have the advantage that effective translational movement of the magnetic microparticles could be achieved with the rotational motions of the magnetic microparticles caused by the rotating magnetic field being converted into the translational movements.

[0051] Examples could make it possible that controlled particle trajectories could be achieved by controlling the dynamic magnetic field.

[0052] Examples may allow for a controlling of magnetic microparticles in an unsupervised way, i.e., without a feedback through a microscope or the like. The magnetic microparticles may rather react to the dynamic magnetic field in a predefined way and their translational movements may be controlled such that the whole suspension is covered, e.g., the whole area of a surface of a substrate covered by the suspension.

[0053] For example, the magnetic microparticles rotate with a rotational frequency of 1 Hz to 100 Hz. In an example, the magnetic microparticles rotate with a rotational frequency of 1 Hz to 50 Hz, preferably of 5 Hz to 20 Hz, and more preferably of 10 Hz to 15 Hz.

[0054] Examples could have the advantage that the specified rotational frequency range may provide a sweet spot between efficient movement of the magnetic microparticles through the solution and efficient coupling of the magnetic microparticles to the biological target particles.

[0055] For example, the rotational frequency, i.e., the rotational speed of the magnetic microparticles may be 5 to 20 Hz. Examples may avoid a domination of rotational fluidic forces at high frequencies. If such rotational fluidic forces become too large, they may even push aside or away biological target particles, preventing an interaction. On the other hand, if the rotational speed is small, also the resulting translational speed may be small, resulting in a time required to sort the biological target particles to be rather high.

[0056] In an example, the magnetic microparticles are spherical particles.

[0057] The spherical shape may, e.g., facilitate a rotational movement of the magnetic microparticles. Examples could have the advantage that uniform motion could be achieved, resulting from the spherical shape minimizing drag and irregular flow during sorting. Examples could make it possible that reproducible particle behavior may be achieved, resulting from the symmetry of spherical microparticles facilitating predictable magnetic responses.

[0058] For example, the magnetic microparticles have a diameter of at least 0.5 pm. For example, the magnetic microparticles have a diameter of 0.5 pm to 8 pm. For example, the magnetic microparticles have a diameter of at least 0.75 pm. For example, the magnetic microparticles have a diameter of 0.75 pm to 8 pm.

[0059] In an example, the magnetic microparticles have a diameter of 1 pm to 8 pm, preferably of 1.5 pm to 3 pm, and more preferably of 1.75 pm to 2.25 pm. For example, the magnetic microparticles have a diameter of 2 pm.

[0060] Examples could have the advantage that an optimal balance between surface area and volume could be achieved, resulting from the defined particle diameter range enhancing magnetic coupling and fluid dynamics. Examples could make it possible that improved interaction with biological targets may be achieved, resulting from the particle size being tailored to maximize binding efficiency.

[0061] In an example, the magnetic microparticles have a surface-to-volume ratio of 3 to 0.3, preferably of 2 to 1, more preferably of 1.75 to 1.25. For example, the magnetic microparticles have a surface-to-volume ratio of 1.5.

[0062] Examples could have the advantage that increased effective reaction surface could be achieved, resulting from the optimized surface-to-volume ratio enhancing interactions with target particles. Examples could make it possible that higher sensitivity in particle sorting may beachieved, resulting from improved binding and coupling efficiency due to the specific surface characteristics.

[0063] For example, smaller particles with a larger surface-to-volume ratio may contribute to an increased interaction with the biological target particles.

[0064] In an example, the magnetic microparticles comprise a pre-magnetized ferromagnetic component providing the permanent net magnetic moment of the magnetic microparticles.

[0065] Examples could have the advantage that reliable magnetic responsiveness could be achieved, resulting from the inclusion of a pre-magnetized ferromagnetic component ensuring a consistent net magnetic moment of the magnetic microparticles. Examples could make it possible that sustained magnetic performance may be achieved, resulting from the inherent stability of the ferromagnetic material under varying operational conditions.

[0066] The pre-magnetized ferromagnetic component of the magnetic microparticles may, e.g., be implemented in form of thin film ferromagnetic coating. The thin film ferromagnetic coating may, e.g., comprise Ni, Co, and / or FePt.

[0067] The pre-magnetized ferromagnetic component of the magnetic microparticles may, e.g., be implemented in form of nanoparticles doped into a matrix of the magnetic microparticles. The nanoparticles may, e.g., comprise FePt and / or FeaC .

[0068] A base material of the magnetic microparticles may, e.g., be of organic origin, like Poly(lactide-co-glycolide). The base material of the magnetic microparticles may, e.g., be of inorganic origin, like silica. The base material may, e.g., be synthesized with various methods comprising one or more of the following: emulsion polymerization, spray drying, microfluidics, precipitation, coacervation, electrospraying, solvent evaporation, template-assisted synthesis, self-assembly methods.

[0069] The pre-magnetized ferromagnetic component, enabling the translational movements of the magnetic microparticles, may, e.g., be incorporated into the magnetic particles during and / or after a synthesis of the particles.

[0070] For example, a maximum magnetic field strength of the applied dynamic magnetic field is lower than a coercivity of the pre-magnetized ferromagnetic component of the magnetic microparticles.

[0071] Examples may have the beneficial effect that the magnetic features of the magnetic microparticles remain unaltered by the applied dynamic magnetic field.

[0072] In an example, the magnetic microparticles are magnetic Janus microparticles comprising a first shell section and a second shell section, which is different from the first shell section. The first shell section comprises the pre-magnetized ferromagnetic component. The second shell section comprises the target-specific surface coupling elements.

[0073] Examples could have the advantage that multifunctional particle behavior could be achieved, resulting from the dual-shell design that segregates magnetic and biochemical functionalities. Examples could make it possible that enhanced specificity and control may be achieved, resulting from the distinct roles of the Janus particle's shell sections in magnetic response and target binding.

[0074] For example, the ferromagnetic component comprises ferromagnetic nanoparticles arranged in the first shell section. For example, the shell is a polymer shell.

[0075] For providing magnetic Janus microparticles, e.g., hollow spherical base bodies may be fabricated using a base material. The base material may, e.g., be of organic origin, like Poly(lactide-co-glycolide), or of inorganic origin, like silica. The base material may, e.g., be synthesized with various methods comprising one or more of the following: emulsion polymerization, spray drying, microfluidics, precipitation, coacervation, electrospraying, solvent evaporation, template-assisted synthesis, self-assembly methods.

[0076] On the prepared base bodies, a ferromagnetic component, e.g., in form of a thin layer of nickel may be deposited, e.g., using a sputter coater. Furthermore, a passivation layer, e.g., in form of a thin layer of gold may be added sequentially, e.g., using the sputter coater. The nickel may introduce magnetic properties, i.e., enabling a net magnetic moment, while the gold may serve as a passivation layer for the magnetic microparticles, preventing the ferromagnetic component from oxidizing and / or causing toxicity to cells. Since sputtering is a positional deposition method, only half of the base bodies may be covered with the ferromagnetic component, e.g., in form of a thin film ferromagnetic coating. Thus, magnetic Janus microparticles may be fabricated.

[0077] By controlling a size of the ferromagnetic component, e.g., a thickness of the nickel, a size of a resulting net magnetic moment of the magnetic Janus microparticles may be influenced. If the ferromagnetic component is too, e.g., if too much nickel is deposited, the magnetic Janusmicroparticles may magnetically aggregate, preventing an effective usage for a magnetic sorting method. A critical thickness may, e.g., depend on the size of the magnetic Janus microparticles. For example, layers of 20 nm Ni and 50 nm Au may be used for 2 pm magnetic Janus microparticles, while layers of 60 nm Ni and 50 nm Au may be used for larger particles. Due to an increased surface to volume ratio, 2 pm magnetic Janus microparticles may have relatively more magnetic content and tend to aggregate with a thinner film compared to larger particles.

[0078] After the deposition, the magnetic Janus microparticles may be magnetized to be able to realize translational movements using a dynamic magnetic field, e.g., a rotational magnetic field. For example, an out-of-plane magnetization may be used. For example, a 1.8 T uniform magnetic field may be used. For example, a uniform magnetic field of 200 to 500 mT may be enough as a coercivity of a thin film ferromagnetic coating may, e.g., be 5 to 20 mT. Thus, saturation may be reached already around 200 mT. After the magnetization, the magnetic Janus microparticles may, e.g., be transferred to a liquid phase so that they can be further utilized.

[0079] Different materials may be used to fabricate similar types of magnetic Janus microparticles. For example, silica microparticles may be replaced by PMMA microparticles, nickel may be replaced by cobalt or some other alloys, gold may be replaced by titanium and so on. For example, ferromagnetic nanoparticles embedded into polymer matrices may be used rather than a thin film ferromagnetic coating.

[0080] For actively controlling translational movements of magnetic Janus microparticles, a dynamic magnetic field B(t), e.g., in form of a rotating magnetic field, may be used. The magnetic Janus microparticles have a net magnetic moment, e.g., due to a pre-magnetized ferromagnetic component comprised by the magnetic Janus microparticles. The rotating magnetic field may cause a rotation of the magnetic Janus microparticles with a rotational speed O. The rotational speed O may be matched with a rotational rate of the dynamic magnetic field and converted to translational movements of the magnetic Janus microparticles with a translational speed v.Microscale physics in fluids may be rather different from macroscale physics as viscous forces may dominate over inertial forces, where the Reynolds number is much less than unity (Re « 1). At such a low Reynolds number regime, an active propulsion mechanism may rely on a breaking of a flow-field symmetry around the magnetic Janus microparticles in the suspension, which may result in a net translational movement.

[0081] Upon an application of the rotational magnetic field, the magnetic Janus microparticles with their net magnetic moment want to align themselves with the magnetic field resulting in acontinuous rotation with the rotational speed of O. This rotation of the magnetic Janus microparticles is converted to translational movements with the speed of v, e.g., along a surface of a substrate by breaking the flow symmetry around the magnetic Janus microparticles in the suspension. The surface of the substrate may form a nearby boundary responsible for the breaking of the flow symmetry around the magnetic microparticle in the suspension, when the magnetic Janus microparticles rotate. Due to the breaking of the flow symmetry, the magnetic Janus microparticles may move on a hydrodynamic liquid layer provided by the liquid of the suspension translationally along the surface of the substrate.

[0082] The rotational magnetic field magnitude may be lower than a coercivity of the magnetic material incorporated into the magnetic microparticles. If this condition satisfies, the magnetic microparticles may behave like a ferromagnetic material and rotation may takes place. By keeping the rotational magnetic field magnitude lower than the coercivity of the magnetic material, a reprogramming in the magnetic material may be avoided. Typical magnetic field magnitude may, e.g., be between 5 to 10 mT.

[0083] Translational movements may be achieved at the microscale, as Brownian motion dominates at the nanoscale. Similar Translational movements may be achievable with microparticles, e.g., as small as 1 pm. However, for smaller particles efficiency may decrease as surface forces become dominant. When magnetic particles are too far from a nearby substrate, which is the case for small particles, they may not be able to perform translational movements.

[0084] In an example, the magnetic microparticles form paramagnetic and / or superparamagnetic chains. The magnetic microparticles may, e.g., be paramagnetic microparticles, which under a magnetic field, create chains, which have a quasi-magnetic moment due to a shape-anisotropy effect and may perform translational movements.

[0085] Examples could have the advantage that collective magnetic behavior could be achieved, resulting from the formation of paramagnetic and / or superparamagnetic chains enhancing the overall magnetic response. Examples could make it possible that improved alignment and sorting efficiency may be achieved, resulting from the cooperative effects among chained microparticles during separation.

[0086] In an example, the translational movements of the magnetic microparticles break a diffusion limit for particle movements within the suspension.

[0087] Examples could have the advantage that accelerated separation kinetics could be achieved, resulting from breaking the natural diffusion limit through active translational movement. Examples could make it possible that higher throughput in particle separation may be achieved, resulting from the increased mobility overcoming diffusion constraints.

[0088] In an example, the method further comprises controlling the dynamic magnetic field for controlling the translational movements of the magnetic microparticles along a predefined path.

[0089] Examples could make it possible that precise sorting patterns may be achieved, resulting from the ability to customize the movement trajectory of magnetic microparticles. Furthermore, examples could have the advantage that targeted particle routing could be achieved, resulting from the controlled dynamic magnetic field guiding particles along predefined paths.

[0090] For example, some randomness may be comprised by the predefined path. Examples of predefined paths may, e.g., comprise straight-line trajectories such as Boustrophedon paths, a sector search, or creeping line patterns. Examples of predefined paths may, e.g., comprise geometric configurations including square, circular, hexagonal, or triangular grid arrangements. Examples of predefined paths may, e.g., comprise curvilinear paths such as Archimedean or logarithmic spirals, sinusoidal or wave-like pattern. Examples of predefined paths may, e.g., comprise randomized trajectories inspired by Brownian motion or Monte Carlo-based exploration. Examples of predefined paths may, e.g., comprise hybrid strategies combining linear and curvilinear paths for enhanced coverage efficiency.

[0091] In an example, the suspension is provided on a surface of a substrate and the translational movements of the magnetic microparticles induced by the applied dynamic magnetic field are translational movements along the surface of the substrate.

[0092] Examples could have the advantage that enhanced control of particle movement could be achieved, resulting from confining the suspension to a substrate surface that directs translational motion. Examples could make it possible that reduced interference from bulk fluid dynamics may be achieved, resulting from the movement being restricted along the substrate surface.

[0093] For example, the magnetic microparticles move on a hydrodynamic liquid layer translationally along the surface of the substrate.

[0094] For example, the magnetic microparticles as well as the biological target particles may be arranged near the surface of the substrate due to sedimentation. Thus, translational movements of the magnetic microparticles along the surface of the substrate may result in an effective interaction between the magnetic microparticles and the biological target particles.

[0095] In an example, the dynamic magnetic field extends across the complete surface of the substrate. The translational movements of the magnetic microparticles extend across the complete surface of the substrate.

[0096] Examples could have the advantage that uniform treatment across the substrate could be achieved, resulting from the dynamic magnetic field extending over the complete surface.Examples could make it possible that consistent separation performance may be achieved, resulting from the homogeneous application of magnetic forces throughout the substrate area.

[0097] For example, the translational movements of the magnetic microparticles along the predefined path extend across the complete surface of the substrate.

[0098] For example, the dynamic magnetic field may be controlled in such a way that the resulting translational movements of the magnetic microparticles are configured such that the magnetic microparticles may repeatedly cross every subsection of the surface of the substrate, which is comparable in size with a size of the biological target particles, multiple times. Examples may ensure a thorough and uniform interaction between the magnetic microparticles and the biological target particles across the entire substrate. Thereby an efficiency and / or effectiveness of the isolation and / or separation resulting from the magnetic sorting method may be improved.

[0099] For example, the suspension extending within an area of the surface of the substrate, which is smaller than a total area of the surface of the substrate. For example, the translational movements of the magnetic microparticles extend across the area of the surface of the substrate, within which the suspension extends. For example, the translational movements of the magnetic microparticles along the predefined path extend across the area of the surface of the substrate, within which the suspension extends.

[0100] In an example, the surface of the substrate is a non-adhesive surface with respect to the biological target particles. Furthermore, the substrate may also be a non-adhesive surface with respect to the other biological particles comprised by the suspension.

[0101] Examples could have the advantage that non-specific binding is minimized, resulting from the substrate's non-adhesive properties toward biological target particles and / or the other biological particles. For example, an unwanted adhesion of the biological target particles and / or the other biological particles of the suspension on the substrate surface may be prevented. Examples could make it possible that a higher efficiency of sorting and thus a higher purity in a resulting sorted sample after separation may be achieved.

[0102] For example, the surface of the substrate may be a sterile surface.

[0103] For example, the surface of the substrate may be modified using a coating and / or a surface treatment for rendering the surface non-adhesive with respect to the biological target particles and / or the other biological particles. Examples may ensure that the biological target particles and / or the other biological particles do not anchor themselves to the surface.

[0104] In an example, the non-adhesive surface comprises one or more of the following: poly-HEMA, polyethylene glycol, polytetrafluoroethylene, a hydrophilic polymer brush, a silicone-based anti-fouling coating, zwitterionic polymers, a superhydrophobic surface, polyethylene oxide, a fluoropolymer coating, amphiphilic block copolymer.

[0105] Examples may comprise a treatment of the surface with polyHEMA, i.e., poly(2-hydroxyethyl methacrylate, which resists protein adsorption and cellular attachment by forming a hydration layer or steric barrier on the surface. Examples may comprise a treatment of the surface with polyethylene glycol (PEG), which resists protein adsorption and cellular attachment by forming a hydration layer or steric barrier on the surface. Examples may comprise a treatment of the surface with polytetrafluoroethylene (PTFE) for its hydrophobic, low-adhesion properties. Examples may comprise a treatment of the surface with a hydrophilic polymer brush, such as polyethylene oxide) (PEO) and / or poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), which may create a hydrated, non-fouling barrier on the surface. Examples may comprise selfassembled monolayers (SAMs) arranged on the surface, which may be customized with nonfouling functional groups, like PEG, to prevent a binding. Examples may, e.g., comprise an alginate and / or polyvinyl alcohol (PVA) coating on the surface, which may offer hydrated surfaces that inhibit attachment. Examples may comprise a silicone-based coating, like modified polydimethylsiloxane (PDMS), which may create a non-adhesive surface through hydrophobicity. Examples may comprise a coating using zwitterionic polymers, such as poly(sulfobetaine methacrylate) (PSBMA), which may create a non-adhesive surface through balanced charge distribution.

[0106] In an example, the substrate is provided by one of the following: a Petri dish, a microfluidic chip, a cartridge.

[0107] Examples could have the advantage that adaptability to various laboratory setups could be achieved.

[0108] In an example, the target-specific surface coupling elements comprise one or more of the following: surface characteristics, targeting moieties.

[0109] Examples could have the advantage that enhanced binding specificity could be achieved, resulting from the inclusion of tailored surface coupling elements like targeting moieties or specific surface characteristics. Examples could make it possible that increased capture efficiency may be achieved, resulting from the optimized interaction between the coupling elements and the biological target particles.

[0110] For example, a surface section of the magnetic particles comprised by the shell section, i.e., a surface section of the shell section, may be covered and / or chemically conjugated with targeting moieties.

[0111] Such targeting moieties may, e.g., be configured for targeting surface antigens of the biological target particles.

[0112] In an example, the targeting moieties comprise one or more of the following: antibodies, aptamers, ligands, peptides, molecules, carbohydrates, glycoproteins, glycolipids, nanobodies, adhesion molecules, metabolic markers.

[0113] Antibodies may, e.g., comprise epCAM, HER2, and / or CD family antibodies, like CD20, CD45, etc. Aptamers may, e.g., comprise SGC8, which is configured to bind to PTK7 expressing cells, which is typically the case with cancer cells. Ligands may, e.g., comprise folate, which is overexpressed some types of cancer cells. Peptides may, e.g., comprise RGD Peptide, which is a adhesion peptide. Glycoproteins may, e.g., comprise MUC1, which may be expressed in different types of cells. Adhesion molecules may, e.g., comprise the selectin family, which may be found more in endothelial cells. Glycolipids molecules may, e.g., comprise gb3, which is likely to be expressed in tumors.

[0114] Targeting moieties refer to specific molecules and / or structures that are configured to identify, bind to, and / or interact selectively with particular biological particles, e.g., within a heterogeneous mixture of biological particles. Such moieties enable a selective isolation,enrichment, and / or depletion of biological target particles comprising the respective moieties. Targeting moieties may, e.g., comprise cell surface proteins, which are clusters of differentiation (CD) molecules, like, e.g., CD34, CD45, and / or CD3. Targeting moieties may, e.g., comprise adhesion molecules, like EpCAM, VCaml, and / or ICAM-1. Targeting moieties may, e.g., comprise receptors, such as growth factor receptors and / or hormone receptors. Targeting moieties may, e.g., comprise integrins, such as a7-integrin and / or pi-integrin. Targeting moieties may, e.g., comprise nanobodies, antibodies, glycoproteins, glycolipids, carbohydrate antigens, mucins, and / or gangliosides. Targeting moieties may, e.g., comprise membrane-associated enzymes, which are, e.g., alkaline phosphatase and / or metalloproteinases. Targeting moieties may, e.g., comprise major histocompatibility complex (MHC) class I and / or class II molecules, tumor-associated antigens, specific tissue antigens, and / or lineage-specific markers. Targeting moieties may, e.g., comprise artificially introduced markers comprising fluorescent proteins, like, e.g., GFP and / or RFP, affinity tags, like, e.g., His-tag and / or FLAG-tag. Targeting moieties may, e.g., comprise metabolic markers, such as enzymes involved in specific metabolic pathways and / or metabolites unique to certain cell types. Molecules may, e.g., be small molecules, like biotin. Small molecules may be molecules with less than 900 to 100 Da. Biotin has 320 Da MW.

[0115] Such targeting moieties may be utilized in various coupling configurations between magnetic microparticles and biological target particles. Coupling configurations may, e.g., comprise an antibody-based coupling, which uses monoclonal and / or polyclonal antibodies that specifically bind to cell surface markers of the biological target particles. Coupling configurations may, e.g., comprise an aptamer-based coupling, which employs synthetic oligonucleotides that bind to specific cell surface structures of the biological target particles. Coupling configurations may, e.g., comprise an affinity ligand coupling, which utilizes natural ligands or synthetic molecules that bind to specific cellular receptors of the biological target particles. Coupling configurations may, e.g., comprise a metabolic labelling, which exploits and targets unique metabolic properties of certain cell types of biological target particles.

[0116] The choice of target-specific surface coupling elements to be used may depend on the specific type biological target particles of interest, the heterogeneity of a sample provided in form of the suspension, and / or intended additional downstream applications. Target-specific surface coupling elements may be used individually or in combinations to increase the specificity and / or purity of a resulting isolated population of biological target particles.

[0117] Target-specific surface coupling elements, like targeting moieties, may, e.g., be conjugated to or in conjunction with fluorescent dyes for an additional flow cytometry-based cellsorting method, magnetic microparticles with various densities for an additional density-based cell sorting method, affinity matrices in a microfluidic device, and / or capture antibodies in an additional immunoaffinity-based separation method.

[0118] In an example, the biological target particles comprise one or more of the following types of biological particles: cells, subcellular components, microorganisms, multicellular structures, cell-derived structures, genetically modified biological microentities, phenotypically modified biological microentities.

[0119] In an example, the other biological particles comprise one or more of the following types of biological particles: cells, subcellular components, microorganisms, multicellular structures, cell-derived structures, genetically modified biological microentities, phenotypically modified biological microentities.

[0120] Biological particles, i.e., the biological target particles as well as the other biological particles comprised by the suspension, may be particles containing genetic information that may be configured for replication, i.e., for replicating itself and / or for being replicated in a biological system. Biological particles may encompass a wide range of cellular and subcellular components, including, e.g., nucleic acids, like DNA, RNA, and / or genes. Biological particles may, e.g., comprise proteins, peptides, and / or microorganisms, like bacteria, viruses, and / or fungi. Biological particles may, e.g., comprise cells, i.e., plant, animal, and / or human cells, and / or cell culture samples with or without genetic modifications. Cells may, e.g., comprise mammalian cells, like human and / or animal cells, plant cells, microbial cells, like bacteria and / or yeast, immune cells, like T cells, B cells, and / or NK cells, blood cells, like red blood cells, white blood cells, and / or platelets. Subcellular components may, e.g., comprise nucleic acids, like DNA, RNA, and / or genes, proteins, polypeptides including antibodies, cell organelles, like mitochondria and / or chloroplasts. Microorganisms may, e.g., comprise viruses, bacteria, fungi, and / or protozoa. Cell-derived structures may, e.g., comprise exosomes, microvesicles, and / or liposomes. Multicellular structures may, e.g., comprise spheroids, organoids, and / or tissue samples. Genetically and / or phenotypically modified biological cells may, e.g., including genetically engineered cells, transformed cells, fused cells, like hybridomas, and / or induced pluripotent stem cells. Biological particles may, e.g., particles that can be isolated from their natural environment, synthetically or recombinantly produced, and / or modified through genetic engineering or other biotechnological processes.

[0121] The biological target particles may, e.g., comprise specific surface markers, antigens, and / or receptors that may be used for a selective coupling of the magnetic microparticles to the biological target particles. These may include cell surface proteins, including clusters of differentiation (CD) proteins and adhesion molecules, e.g., EpCAM, glycoproteins, lipid structures, and / or artificially introduced markers, like fluorescent proteins and / or affinity tags. The coupling may enable a magnetic labeling of the biological target particles using the magnetic microparticles for an isolation, separation, and / or sorting of the biological target particles. The biological particles may, e.g., be provided in complex mixtures such as whole blood, tissue homogenates, liquid biopsies, and / or environmental or cell culture samples.

[0122] For example, the liquid comprises one of the following: phosphate buffered saline (PBS), Hank's balanced salt solution (HBSS), a cell culture medium based liquid, a water-based liquid. For example, 0.1% w / v albumin solution supplemented with 5 mM EDTA in lx PBS may be used.

[0123] For example, the suspension is provided as a stagnant fluid.

[0124] For example, the suspension is provided using a continuous flow system integrated with microfluidic channels.

[0125] In an example, the method further comprises analyzing the biological target particles and / or the other biological particles after the separating.

[0126] For example, one or more of the following analyzing techniques are used: flow cytometry, microscopy, molecular and / or immunological assays, proteins, or other biomolecules, western blotting, mass spectrometry, single-cell RNA sequencing.

[0127] Separated biological particles may, e.g., comprise the other biological particles and / or the biological target particles provided in form of the magnetic particle complexes. A flow cytometry may, e.g., be used for quantifying and / or characterizing of surface markers, size, and / or granularity of separated biological particles. A microscopy may, e.g., be used for visualizing and / or analyzing a morphology and / or specific labeling of separated biological particles. The microscopy may, e.g., including fluorescence and / or confocal microscopy.Molecular assays, such as PCR, qPCR, and / or ELISA, may be used for detecting and / or quantifying nucleic acids, proteins, and / or other biomolecules. A western blotting and / or mass spectrometry may be used for a detailed protein characterization. A single-cell RNA sequencing may, e.g., be used for analyzing gene expression profiles of individual cells. The aforementioned techniquesmay, e.g., provide a comprehensive insight into the separated biological particles and / or enable a further functional analysis, classification, and / or molecular profiling.

[0128] Examples could have the advantage that detailed post-separation analysis could be achieved, resulting from the integration of advanced techniques such as flow cytometry and microscopy.

[0129] Combining the magnetic particle-based separation with other microfluidic and / or analyzing techniques may provide an integrated and automated platform biological particle analysis and / or manipulation.

[0130] Examples may, e.g., comprise an adjusting of a ratio of the magnetic microparticles to the biological target particles. The ratio of the magnetic microparticles to the biological target particles may, e.g., be adjusted to enhance the interaction between the magnetic microparticles and the biological target particles, where a higher ratio may, e.g., improve a likelihood of coupling between the magnetic microparticles and the biological target particles.

[0131] Examples may, e.g., comprise an adjusting of a size of the magnetic microparticles. The size of the magnetic microparticles may, e.g., be adjusted to balance an effective translational movement of the magnetic microparticles and a magnetic responsiveness of the same.

[0132] Examples may, e.g., comprise an adjusting of a path-planning for the actively controlled translational movements of the magnetic microparticles. For example, a planning of the applied dynamic magnetic field and the resulting paths of the magnetic microparticles may be adjusted to ensure an effective modulation of the translational movements of the magnetic microparticles for a suitable area coverage. This may allow for a targeted enrichment, depletion, and / or fractionation of biological particles, e.g., tailored to the specific requirements of the application.

[0133] For example, the suspension may be added with different types of magnetic microparticles with different types of target-specific surface coupling elements configured for selectively coupling to surfaces of different types of biological target particles. Thus, a plurality of different biological target particles may be selectively separated using a plurality of different magnetic microparticles.

[0134] For example, the magnetic microparticles may each be applied with a plurality of different types of target-specific surface coupling elements configured for selectively coupling to surfaces of different types of biological target particles. Thus, the magnetic microparticles may beconfigured to couple to more than one type of biological target particle and a plurality of different biological target particles may be selectively separated using these magnetic microparticles.

[0135] Further disclosed is a computer program for controlling a magnetic sorting system for selectively separating biological target particles from other biological particles within a liquid of a suspension. The magnetic sorting system comprises a suspension inlet component, a magnetic field generator component, a separation component, and a computer component. The computer program comprises machine executable instructions for an execution by the computer component. The execution of the machine executable instructions causes the computer component to control the magnetic sorting system to perform a method comprising controlling the suspension inlet component to provide the suspension. The suspension is added with magnetic microparticles. The magnetic microparticles comprise a permanent net magnetic moment. At least a shell section of each of the magnetic microparticles is applied with targetspecific surface coupling elements configured for selectively coupling to a surface of the biological target particles. The magnetic field generator component is controlled to apply a dynamic magnetic field for actively controlling movements of the magnetic microparticles within the suspension. The applied dynamic magnetic field is configured for inducing the magnetic microparticles to perform translational movements through the suspension and, while moving through the suspension, to couple to the biological target particles via the target-specific surface coupling elements forming magnetic particle complexes. The magnetic field generator component is further controlled to separate the magnetic particle complexes from the other biological particles using the magnetic moment of the magnetic microparticles comprised by the magnetic particle complexes.

[0136] Examples could have the advantage that an automated and precise control of the sorting system could be achieved, resulting from the computer program's execution of coordinated instructions for suspension handling, field generation, and separation.

[0137] Execution of the program instructions by the computer component may, e.g., cause the computer component to control the magnetic sorting system to execute any of the aforementioned examples of the magnetic sorting method for selectively separating biological target particles from other biological particles within a liquid of a suspension using magnetic microparticles.

[0138] The magnetic field generator component may, e.g., comprise an electromagnetic coil configuration, a permanent magnet configuration, or a combination thereof.

[0139] For example, the magnetic sorting system further comprises a substrate. The suspension inlet component is controlled to provide the suspension on a surface of the substrate. The magnetic field generator component is controlled to apply a dynamic magnetic field configured for inducing the translational movements of the magnetic microparticles along the surface of the substrate.

[0140] For example, the magnetic sorting system further comprises a magnetic microparticle inlet component. The magnetic microparticle inlet component is controlled to add the magnetic microparticles to the suspension.

[0141] For example, the magnetic sorting system further comprises an extraction component. The extraction component is controlled to extract the magnetic particle complexes and / or the other biological particles from the suspension.

[0142] An example may comprise a computer program product for controlling a magnetic sorting system for selectively separating biological target particles from other biological particles within a liquid of a suspension. The magnetic sorting system comprises a suspension inlet component, a magnetic field generator component, a separation component, and a computer component. The computer program product comprises a non-transitory computer readable storage medium having program instructions embodied therewith. The program instructions are executable by the computer component. The execution of the machine executable instructions causes the computer component to control the magnetic sorting system to perform a method comprising controlling the suspension inlet component to provide the suspension. The suspension is added with magnetic microparticles. The magnetic microparticles comprise a permanent net magnetic moment. At least a shell section of each of the magnetic microparticles is applied with target-specific surface coupling elements configured for selectively coupling to a surface of the biological target particles. The magnetic field generator component is controlled to apply a dynamic magnetic field for actively controlling movements of the magnetic microparticles within the suspension. The applied dynamic magnetic field is configured for inducing the magnetic microparticles to perform translational movements through the suspension and, while moving through the suspension, to couple to the biological target particles via the target-specific surface coupling elements forming magnetic particle complexes. The magnetic field generator component is further controlled to separate the magnetic particle complexes from the otherbiological particles using the magnetic moment of the magnetic microparticles comprised by the magnetic particle complexes.

[0143] Execution of the program instructions by the computer component may, e.g., cause the computer component to control the magnetic sorting system to execute any of the aforementioned examples of the magnetic sorting method for selectively separating biological target particles from other biological particles within a liquid of a suspension using magnetic microparticles.

[0144] Examples could have the advantage that an automated and precise control of the sorting system could be achieved, resulting from the computer program's execution of coordinated instructions for suspension handling, field generation, and separation.

[0145] Further disclosed is a computer component for controlling a magnetic sorting system for selectively separating biological target particles from other biological particles within a liquid of a suspension. The magnetic sorting system comprising a suspension inlet component, a magnetic field generator component, and a separation component. The computer component comprises a memory with machine executable instructions stored therein for an execution by the computer component. The execution of the machine executable instructions causes the computer component to control the magnetic sorting system to perform a method comprising controlling the suspension inlet component to provide the suspension. The suspension is added with magnetic microparticles. The magnetic microparticles comprise a permanent net magnetic moment. At least a shell section of each of the magnetic microparticles is applied with targetspecific surface coupling elements configured for selectively coupling to a surface of the biological target particles. The magnetic field generator component is controlled to apply a dynamic magnetic field for actively controlling movements of the magnetic microparticles within the suspension. The applied dynamic magnetic field is configured for inducing the magnetic microparticles to perform translational movements through the suspension and, while moving through the suspension, to couple to the biological target particles via the target-specific surface coupling elements forming magnetic particle complexes. The magnetic field generator component is further controlled to separate the magnetic particle complexes from the other biological particles using the magnetic moment of the magnetic microparticles comprised by the magnetic particle complexes.

[0146] Examples could have the advantage that automated and precise control of the sorting system could be achieved using the computer component executing coordinated instructions for suspension handling, field generation, and separation.

[0147] Execution of the program instructions by the computer component may, e.g., cause the computer component to control the magnetic sorting system to execute any of the aforementioned examples of the magnetic sorting method for selectively separating biological target particles from other biological particles within a liquid of a suspension using magnetic microparticles.

[0148] Examples using a computer component for controlling the magnetic sorting system may enable an implementation of the magnetic sorting method in an automated manner, with all steps being executed in a robotic fashion, such that the introduction of biological particles, the adding of the magnetic microparticles, the active controlling of the translational movements of the magnetic microparticles for the interaction with the biological target particles, the separating, the washing, and / or the analyzing may controlled and executed by a robotic system, requiring minimal to no manual intervention. An exemplary sorting system comprising a computer component for controlling the magnetic sorting system may be configured to facilitate a seamless operation, enabling a reproducible, high-throughput processing of biological samples in a fully automated or semi-automated manner, allowing for efficient scalability and ease of integration into laboratory workflows.

[0149] Examples may enable a parallel sorting a for selectively separating different biological target particles in parallel. Different samples of a suspension comprising a mixture of the different biological target particles may be provided and added with different types of magnetic microparticles. The different types of magnetic microparticles may, e.g., differ in the type of target-specific surface coupling elements comprised by the same. Different types of targetspecific surface coupling elements may be configured for selectively coupling to the surfaces of different ones of the different biological target particles comprised by the suspension. Depending on the type of biological target particle to be sorted in a sample, magnetic microparticles with suitable target-specific surface coupling elements may be added. For example, a well plate may be used to provide the different samples in parallel and add the different types magnetic microparticles to the different samples in parallel. Thus, a parallelization of the sorting method for selectively separating different biological target particles from a suspension may be implemented, in particular in an automated way.

[0150] Further disclosed is a magnetic sorting system for selectively separating biological target particles from other biological particles within a liquid of a suspension. The magnetic sorting system comprises a suspension inlet component, a magnetic field generator component, a separation component, and a computer component for controlling a magnetic sorting system.

[0151] Examples could have the advantage that a sorting system for an automated and precise control of a selective separating of biological target particles from other biological particles may be provided. Examples could make it possible that a fully integrated sorting platform could be achieved, resulting from the combination of a suspension inlet, magnetic field generator, separation component, and computer control.

[0152] It is understood that one or more of the aforementioned examples may be combined as long as the combined examples are not mutually exclusive.BRIEF DESCRIPTION OF THE DRAWINGS

[0153] In the following, examples are described in greater detail making reference to the drawings in which:

[0154] Fig. 1 is a block diagram of an exemplary magnetic sorting system,

[0155] Fig. 2 shows an exemplary path of magnetic microparticles through a suspension,

[0156] Fig. 3 shows an exemplary magnetic microparticle in form of a magnetic Janus microparticle,

[0157] Fig. 4 shows an exemplary generation of a translational movement of a magnetic microparticle,

[0158] Fig. 5 illustrates an exemplary dependency of a translational speed of a magnetic microparticle on a frequency of the respective magnetic microparticle,

[0159] Fig. 6 illustrates exemplary sorting methods,

[0160] Fig. 7 illustrates an exemplary targeting of biological target particles using magnetic microparticles,

[0161] Fig. 8 shows exemplary flow cytometry results for a suspension before execution of a magnetic sorting method,

[0162] Fig. 9 shows further exemplary flow cytometry results for the suspension before execution of the magnetic sorting method,

[0163] Fig. 10 shows exemplary flow cytometry results for a suspension after execution of a magnetic sorting method,

[0164] Fig. 11 shows further exemplary flow cytometry results for the suspension after execution of the magnetic sorting method,

[0165] Fig. 12 illustrates an exemplary separating of biological target particles using magnetic microparticles,

[0166] Fig. 13 shows exemplary flow cytometry results for a collected supernatant cell solution,

[0167] Fig. 14 shows further exemplary flow cytometry results for the collected supernatant cell solution,

[0168] Fig. 15 shows exemplary flow cytometry results for a magnetically collected cell pellet solution,

[0169] Fig. 16 shows further exemplary flow cytometry results for the magnetically collected cell pellet solution,

[0170] Fig. 17 shows a flowchart of an exemplary magnetic sorting method, and

[0171] Fig. 18 shows a block diagram of an exemplary computer component for controlling a magnetic sorting system.DETAILED DESCRIPTION

[0172] In the following, similar elements are denoted by the same reference numerals.

[0173] In the following an example of a preparation of magnetic microparticles for a selectively separating of biological target particles from other biological particles within a liquid of a suspension is provided (example 1): The magnetic microparticles were prepared by first forming monolayers of 2-micrometer silica particles on a hydrophilic glass slide. To achieve this, 25 pl of a 5% w / v particle solution was drop-cast onto a 2x2 cm2glass slide and allowed to dry at room temperature. The dried particles were then coated with layers of nickel (Ni, 18 nm) and gold (Au, 50 nm) using sputtering. Ni served as the magnetic component, while Au provided a passivationlayer to prevent oxidation. The sputtering process produced Janus particles, with one hemisphere of each particle consisting of silica and the other covered by the metallic coatings described above.

[0174] After sputtering, the coated particles were magnetized in an out-of-plane direction using a vibrating sample magnetometer with a 1.5 T uniform magnetic field. The magnetized particles were transferred to a liquid phase by sonicating them in ethanol, then collected in a centrifuge tube, centrifuged, and resuspended in phosphate-buffered saline (PBS lx) for further use.

[0175] In the following an example of a conjugation of target-specific surface coupling elements in form of antibodies to the magnetic microparticles is provided (example 1): The conjugation of the target-specific surface coupling elements, i.e., targeting moieties in the form of antibodies here, was achieved using a combination of different chemical strategies. First, hydroxyl groups (-OH) on the silica side of the Janus particles were converted to amino groups (-NH2) by reacting the particles with a 5% v / v solution of (3-Aminopropyl)triethoxysilane in ethanol for 16 hours. The particles were then baked at 80°C for 1 hour and subsequently washed several times with ethanol to remove any unbound molecules.

[0176] Next, the amino groups were converted to biotin by reacting with N-Hydroxysuccinimide-biotin (NHS-biotin). The amino-modified Janus particles were washed thoroughly with dimethyl sulfoxide (DMSO) and then treated with 5 mg / mL NHS-biotin in DMSO for 3 hours at room temperature using a vortex shaker. After the reaction was complete, the particles were washed again several times with DMSO and resuspended in PBS lx.

[0177] The biotin-functionalized Janus particles were then conjugated with fluorescent streptavidin, enabling subsequent binding of biotin-conjugated antibodies. This was achieved by shaking the biotin-modified particles with streptavidin for 45 minutes in PBS lx, followed by extensive washing in PBS lx to prepare for antibody conjugation. Finally, biotin-epCAM antibodies were conjugated to the streptavidin-coated Janus particles by shaking for 45 minutes in PBS lx. To prevent non-specific attachment, the particles were treated with 10% fatty acid-free bovine serum albumin for lh. At the end, the Janus particles were washed with PBS lx for further use.

[0178] In the following an example of a preparation of a non-adhesive surface of a substrate (example 3) is provided: Petri dishes and well plates have been treated with Poly(2-hydroxyethyl methacrylate) (poly-HEMA) solution. Briefly, 12 w / v% poly-HEMA solution was stirred overnight at 65 °C in 95% v / v ethanol in deionized water. Then, the solution was diluted by ten times in 95%v / v ethanol. The diluted solution was added to Petri dishes and kept in a laminar flow hood for 72 hours until the solution slowly dried out. Then, Petri dishes and well plates, respectively, were ready for further experiments.

[0179] In the following an example of a selection of biological target particles in form of cancer cells is provided (example 4): BJ fibroblast cells (CRL-2522) were grown in Eagle's Minimum Essential Medium with 10% v / v fetal bovine serum and 1% v / v penicillin-streptomycin at 37°C in a 5% CO2, 95% air humidified atmosphere. Similarly, CAPAN-2 pancreatic cell lines were grown in McCoy's 5a Medium with 10% v / v fetal bovine serum and 1% v / v penicillin-streptomycin in a similar fashion with BJ fibroblast cells. Separated BJ fibroblast and CAPAN-2 pancreatic cancer cell populations were stained with calcein AM blue and green, respectively, live-cell fluorescent dyes. The cells were incubated with 2 pM calcein AM in PBS for 30 minutes at 37°C. Then, BJ fibroblast cells and CAPAN-2 pancreatic cancer cells were mixed in a falcon tube. The cells were then dispersed in a medium containing 0.1 %w / v bovine serum albumin and 5 mM EDTA in lx PBS with a concentration of 100.000 cells per 75 pL. Then, EpCAM antibody-coated streptavidin-tagged magnetic microparticles were added in a concentration of 500.000 particles per 75 pL in a solution containing 0.1 %w / v bovine serum albumin, 5 mM EDTA in lx PBS. The analysis was performed in a flat bottom poly-HEMA coated 96-well plate. The cells and the magnetic microparticles were mixed in a centrifugation tube with a pipette, each from 75 pL, with a total volume of 150 pL. Then, the mixture was transferred to well plates and placed on a magnetic field generator component to commence the selection process. A dynamic magnetic field in form of a rotating magnetic field was applied for 10 minutes without user interference to enable a selection of the CAPAN-2 cancer cells as the biological target particles with the magnetic microparticles containing anti-epCAM as target-specific surface coupling elements. During the 10-minute magnetic cell selection process, the magnetic microparticles perform rotations resulting in translational movements along the substrate, which lead to a selection of specific cells from the total cell population. This selection is illustrated in Fig. 4. After that process, the cell solution was collected and fluorescence signals measured using a flow cytometer. The separated cell populations were analyzed using a flow cytometer equipped with 488, 555, and 647 nm lasers for fluorescence excitation. Fluorescence intensity was measured using 530 / 30, 570 / 30, and 670 / 30 nm bandpass filters. Forward and side scatter parameters were used to examine intact cells. At least 10,000 events were collected for each sample. While only 2.2% of the tumor cells have been selected before the actively controlled translational movements of the magnetic microparticles, 80.7% of the tumor cells are selected after the magnetic selection process. The results for both cases, i.e., before and after the actively controlled translationalmovements, are illustrated in Fig. 8 and 9 as well as Fig. 10 and 11, respectively. On the other hand, the healthy cell population was not selected by the magnetic microparticles. The red fluorescence emission for the healthy cell population stayed similar, 99.0% and 98.0%, before and after the selection process, respectively. The selection ratio of tumor cells could, e.g., be further increased by adjusting the rotating magnetic field, increasing the number of magnetic microparticles, and / or increasing an assay time.

[0180] In the following an example of a separation of the biological target particles in form of the tumor cells from the cell mixture is provided (example 5): Using the rotating magnetic field, CAPAN-2 cancer cells were selected from a suspension comprising a mixed cell population using magnetic microparticles functionalized with anti-EpCAM antibodies as target-specific surface coupling elements. The magnetic microparticles formed magnetic particle complexes with the selected CAPAN-2 cells and were attracted to the surface of the substrate using a permanent magnet for a magnetic field generation, while the supernatant containing BJ cells was transferred to a falcon tube. This separation is illustrated in Fig. 12. Then, the permanent magnet was removed and the magnetic particle complexes with the CAPAN-2 cells were transferred to another falcon tube. The separated cell populations were analyzed using a flow cytometer equipped with 488, 555, and 647 nm lasers for fluorescence excitation. Fluorescence intensity was measured using 530 / 30, 570 / 30, and 670 / 30 nm bandpass filters. Forward and side scatter parameters were used to examine intact cells. At least 10,000 events were collected for each sample. Fluorescence values of tumor and healthy cell populations were compared to assess separation efficiency. The percentage of calcein-green-positive tumor cells in each population was determined using various gating processes compared to calcein-blue-positive healthy cells in each population. While a majority of the cell population in the supernatant (79.0%) was healthy cell population, a majority of the magnetic particle-based selected cell population (75.4%) was cancer cell population. The results of this separation are shown in Fig. 13 and 14 as well as Fig. 15 and 16, respectively. A majority of the cancer cell population (91.15%) in the cell pellet was coupled to magnetic micro particles. The separation quality could, e.g., be further increased by adjusting the magnetic field gradients and / or incorporating multiple washing steps.

[0181] Fig. 1 shows a block diagram of an exemplary magnetic sorting system 100 for selectively separating biological target particles from other biological particles within a liquid of a suspension. The magnetic sorting system comprises a substrate 102, e.g., provided by a container, a suspension inlet component 104, a magnetic microparticle inlet component 106, a magnetic field generator component 108, a separation component, and a computer component120 for controlling at least the magnetic field generator component 108. The separation component may comprise a sorted particle outlet component 110 and a residue outlet component 112.

[0182] The suspension inlet component 104 is controlled to provide the suspension on a surface of the substrate 102. Furthermore, the magnetic microparticle inlet component 106 is controlled to add the magnetic microparticles to the suspension. The magnetic microparticles comprise a permanent net magnetic moment. At least a shell section of each of the magnetic microparticles is applied with target-specific surface coupling elements configured for selectively coupling to a surface of the biological target particles. The magnetic field generator component 108 is controlled using the computer component 120 to apply a dynamic magnetic field for actively controlling movements of the magnetic microparticles within the suspension. The applied dynamic magnetic field is configured for inducing the magnetic microparticles to perform translational movements along the surface of the substrate 102 through the suspension and, while moving through the suspension, to couple to the biological target particles via the targetspecific surface coupling elements forming magnetic particle complexes. The dynamic magnetic field may, e.g., be a rotating magnetic field with a specific angular velocity (O) and varying orientation, which ultimately determines the translational movements of the magnetic microparticles in a predetermined area of the substrate 102.

[0183] The magnetic field generator component 108 is further controlled to separate the magnetic particle complexes from the other biological particles using the magnetic moment of the magnetic microparticles comprised by the magnetic particle complexes. The magnetic field generator component 108 may, e.g., comprise an electromagnetic coil configuration, a permanent magnet configuration, or a combination thereof. The sorted particle outlet component 110 of the extraction component may be controlled to extract the magnetic particle complexes. The residue outlet component 112 of the extraction component may be controlled to extract the other biological particles from the suspension.

[0184] The dynamic magnetic field, e.g., a rotating magnetic field, induced by the magnetic field generator component 108 leads to a synchronous rotation of the magnetic microparticles. Such a rotation may cause translational movements of the magnetic microparticles by breaking a flowfield symmetry on the substrate 102 with a certain translational velocity of V, typically multiple body lengths of the magnetic microparticles. By changing the orientation of the dynamic magnetic field, the position of the magnetic microparticles may be precisely controllable, allowing them to cover a specific area in their close vicinity. The same type of translationalmovements by the magnetic microparticles may occur uniformly across the substrate 102 due to the global dynamic magnetic field. Thus, e.g., a complete coverage of the entire surface of the substrate 102 by the translational movements of the magnetic microparticles may be ensured. In other words, a high number of magnetic microparticles on the substrate 102 may continuously move in a coordinated manner, ensuring that the entire surface of the substrate 102 may be efficiently swept and interacted with as the dynamic magnetic field directs the movements of the magnetic microparticles. An adjusting of the properties of the dynamic magnetic field generated by the magnetic field generator component 108 may allow to directly determine both the duration and quality of the assay. For example, smaller angular velocities (O) of rotation induced in the magnetic microparticle would result in lower translational velocities (V) of the magnetic microparticles, thereby significantly increasing the duration of the assay. Additionally, the predetermined path that the magnetic microparticles follow may influence the assay time.

[0185] The computer component 120 may, e.g., be configured for controlling the complete magnetic sorting system 100. The computer component 120 may comprise a memory with machine executable instructions stored therein for an execution by the computer component 120. The execution of the machine executable instructions may cause the computer component 120 to control the magnetic sorting system 110 to perform a sorting method as described above.

[0186] Fig. 2 shows an exemplary path 150 of a magnetic microparticle 140 on a substrate 102 through a suspension. The magnetic microparticle 140 is actively controlled using a dynamic magnetic field to execute a translational movement along the path 150 with a translational velocity V. The magnetic microparticle 140 may, e.g., follow different predetermined movement directions at different time points (t). While following the path 150 through the suspension, the magnetic microparticle 140 will reach different positions on the substrate 102 at different points in time (t). The exemplary path 150 shown in Fig. 2 is a spiral path.

[0187] The magnetic particle 140 may comprise a pre-magnetized ferromagnetic component, e.g., a thin film ferromagnetic coating and / or embedded ferromagnetic magnetic nanoparticles, to align with a dynamic magnetic field, e.g., a rotating magnetic field, enabling effective movements of the magnetic particle 140 on the substrate 102. Additionally or alternately, the magnetic particles 140 may be configured to form superparamagnetic or paramagnetic microparticle chains.

[0188] Fig. 3 shows an exemplary magnetic microparticle 140 in form of a magnetic Janus microparticle. The magnetic Janus microparticle 140 comprises a first shell section 170 and asecond shell section 172, which is different from the first shell section 170. The first shell section 170 may comprise a pre-magnetized ferromagnetic component 180 providing a permanent net magnetic moment m of the magnetic Janus microparticle 140. The first shell section 170 may be magnetized. The magnetization direction 182 of the magnetic Janus microparticle 140, i.e., the first shell section 170, is e.g., pre-programmed to the direction indicated by the arrow 182.

[0189] The second shell section 172 may comprise target-specific surface coupling elements 190 configured for selectively coupling to a surface of biological target particles.

[0190] Fig. 3 further shows a cross-section 184 of the first shell section 170. The magnetic Janus microparticle 140 may, e.g., comprise a hollow spherical base body 186 made of a base material. The base material of the magnetic Janus microparticle 140 may, e.g., be of inorganic origin, like silica, or of organic origin, like Poly(lactide-co-glycolide). The pre-magnetized ferromagnetic component 180 of the magnetic Janus microparticle 140 may, e.g., be implemented in form of a thin film ferromagnetic coating as shown in Fig. 3. The thin film ferromagnetic coating may, e.g., comprise Ni, Co, and / or FePt. The pre-magnetized ferromagnetic component 180 of the magnetic Janus microparticle 140 may alternatively, e.g., be implemented in form of nanoparticles doped into a matrix of the magnetic Janus microparticle 140. The nanoparticles may, e.g., comprise FePt and / or FeaC . The pre-magnetized ferromagnetic component 180, enabling the translational movement of magnetic Janus microparticle 140, may, e.g., be incorporated into magnetic Janus microparticle 140 during and / or after a synthesis of the particle. The pre-magnetized ferromagnetic component 180 of the first shell section 170 of the magnetic Janus microparticle 140 may, e.g., be covered by a passivation layer 188, e.g., to prevent oxidation. The passivation layer 188 may, e.g., be made from gold. The passivation layer 188 may, e.g., be impermeable for ions.

[0191] Fig. 4 shows an exemplary generation of a translational movement of a magnetic microparticle 140, e.g., in form of a magnetic Janus microparticle, using a dynamic magnetic field B(t), e.g., in form of a rotating magnetic field. The magnetic microparticle 140 has a net magnetic moment m, e.g., due to a pre-magnetized ferromagnetic component comprised by the magnetic microparticle 140. The rotating magnetic field causes a rotation of the magnetic microparticle 140 with a rotational speed O. The rotational speed O may be matched with a rotational rate of the dynamic magnetic field and converted to a translational movement of the magnetic microparticle 140 with a translational speed v. Microscale physics in fluids may be rather different from macroscale physics as viscous forces may dominate over inertial forces, where the Reynolds number is much less than unity (Re « 1). At such a low Reynolds number regime, anactive propulsion mechanism may rely on a breaking of a flow-field symmetry around the magnetic microparticle 140 in the suspension, which may result in a net translational movement as illustrated in Fig. 4.

[0192] Upon an application of the rotational magnetic field, the magnetic microparticle 140 with its net magnetic moment m wants to align itself with the magnetic field resulting in a continuous rotation with the rotational speed of O. This rotation of the magnetic microparticle 140 is converted to a translational movement with the speed of v along a surface of the substrate 102 by breaking the flow symmetry around the magnetic microparticle 140 in the suspension. The surface of the substrate 102 may form a nearby boundary responsible for the breaking of the flow symmetry around the magnetic microparticle 140 in the suspension, when the magnetic microparticle 140 rotates. Due to the breaking of the flow symmetry, the magnetic microparticle 140 may move on a hydrodynamic liquid layer provided by the liquid of the suspension translationally along the surface of the substrate 102.

[0193] Fig. 5 illustrates an exemplary dependency of a translational speed of a magnetic microparticle on a frequency, i.e., rotational speed, of the respective magnetic microparticle. The dependency is shown for a magnetic microparticle in form of a magnetic Janus particle with a 8 pm diameter and a magnetic component provided by a 60 nm coating layer of Ni applied to half of the magnetic Janus particles shell. As illustrated in Fig. 5, the translational speed of the magnetic microparticle is directly coupled by the rotational speed. There may be a limit for the rotational speed, that is related to the amount of magnetic material in the magnetic microparticle and field strength. After a rotating frequency of around 120-130 Hz, the speed drops because the magnetic torque created no longer matches the fluidic torque.

[0194] Fig. 6 illustrates exemplary sorting methods. In the upper row of Fig. 6, steps of an exemplary sorting method with a positive selection are shown. In the lower row of Fig. 6, steps of an exemplary sorting method with a negative selection are shown. A suspension 160 comprising a mixture of biological target particles and other biological particles is provided. In a first step of the exemplary sorting method, the liquid suspension 160 comprising biological target particles 142 as well as other biological particles 146 is provided. Magnetic microparticles 140 are added to the suspension 160, which comprise target-specific surface coupling elements configured for selectively coupling to a surface of the biological target particles 142. In a second step of the exemplary sorting method, the magnetic particles 140 are actively controlled by applying a dynamic magnetic field generated using a magnetic field generator component. The applied dynamic magnetic field is configured for inducing the magnetic microparticles 140 to performtranslational movements through the suspension 160 and, while moving through the suspension 160, to couple to the biological target particles 142 via the target-specific surface coupling elements forming magnetic particle complexes 144. The method using actively controlled magnetic microparticles 140 may ensure a higher probability of collisions between the magnetic microparticles 140 and the biological particles 142, 146, in particular the biological target particles 142, thereby increasing process efficiency. The magnetic field generator component may, e.g., be controlled to allow the magnetic microparticles 140 to cover the entire substrate 102 multiple times in a time-efficient way.

[0195] In the second step, the actively controlled magnetic microparticles 140 overcome the diffusion limit of the suspension 160, which defines the limit of the slow process of molecules spreading or mixing in the suspension 160 solely through passive diffusion. This limitation is particularly significant at the microscale and in microfluidic systems, where mixing becomes inefficient due to the small scale and the reduced movement of particles. At these scales, particles move slowly, and the natural mixing process may be insufficient to achieve fast or thorough interactions between particles. By actively moving in response to the dynamic magnetic field, the magnetic microparticles 140 are enabled to bypass these microscale limitations. Their controlled movements enable them to navigate through the suspension 160 more effectively, increasing the frequency of interactions with the biological particles 142, 146, in particular the biological target particles 142. This active mixing may enhance the overall process by allowing the magnetic microparticles 140 to reach their targets, i.e., the biological target particles 142, more quickly and uniformly. Consequently, the system may achieve a faster mixing and greater efficiency, overcoming the slow and limited mixing that typically occurs at the microscale. This may lead to faster assay times and improved overall performance of the sorting method.

[0196] In a third step of the sorting method, during and after the magnetic actuation is completed, magnetic particle complexes 144 are formed between the magnetic microparticles 140 and the biological target particles 142. In the case of a positive selection, the biological target particles 142, to which the magnetic microparticles couple, are particles to be kept, while the other biological particles are particles to be removed. In the case of a negative selection, the biological target particles 142, to which the magnetic microparticles couple, are particles to be removed, while the other biological particles are particles to be kept.

[0197] In a fourth step of the sorting method, the separation takes place. The separation of the magnetic particle complexes 144 and thus the biological target particles 142 may be carried out through various methods, e.g., depending on characteristics of the biological particles 142, 146comprised by the suspension 160. A first approach method may involve a controlled actuation of the magnetic microparticles 140 and thus the magnetic particle complexes 144 with the biological target particles 142 to a designated location on the substrate 102. This may allow the magnetic particle complexes 144 to be selectively positioned on the substrate 102, facilitating their separation from the surrounding medium. Such an approach may be straightforward and effective, when a rapid and uncomplicated separation is required. A second method may involve a use of one or more of the following to attract the magnetic microparticles 140 and thus the magnetic particle complexes 144 with the biological target particles 142 to a surface of the substrate 102: a permanent magnet, a configuration of permanent magnets, an electromagnet, a configuration of electromagnets. Once attraction is established, separation may be performed through decantation and / or washing, e.g., using an automatic pipette. A change in a distance and / or currents of the electromagnets and / or a distance of the permanent magnets may enable a controlling of a magnetic field gradient strength, which may, e.g., be adjusted based on the type and size of the particles being handled.

[0198] Fig. 7 illustrates an exemplary targeting of biological target particles 142 in a suspension 160 using magnetic microparticles 140 according to the example 4 described above. The actively controlled translational, rotational movements of the magnetic microparticles 140 may enable a selection of cancer cells, e.g., CAPAN-2 pancreatic cells in case of example 4, as biological target particles 142, while other biological particles 146 comprised by the suspension 160 are healthy cells, e.g., BJ fibroblast cells in case of example 4. The scale bars are 50 pm.

[0199] Fig. 8 and 9 show exemplary flow cytometry results for a suspension before a separation using a magnetic sorting method. The setup corresponds to example 4 described above.Magnetic microparticles, tumor cells as biological target particles, and healthy cells as other biological particles are stained with streptavidin (Red, APC-A), calcein-blue (BV421-A), and calcein-green (FITC-A), respectively. Fig. 8A shows a result of a gating for the total cell population. Fig. 8B shows a result for a gating for the magnetic microparticles. Fig. 9A shows counts of active microparticles, healthy cells, and tumor cells on a forward scattering (FSC-A) histogram. Fig. 8C shows a result for a gating for the tumor cell population. Fig. 8D shows a result for a gating for the healthy cell population. Fig. 9B shows distribution ratios of tumor and healthy cells in total cell population on a green fluorescence emission (FITC-A) histogram. Fig. 8E shows a distribution of all populations on a scatter contour plot with axes of red fluorescence (APC-A) and green fluorescence (FITC-A) emissions. Fig. 8F shows a distribution of all populations on a scatter contour plot with axes of red fluorescence (APC-A) and blue fluorescence (BV421-A) emissions.Fig. 9C shows a count of the healthy cell population on a red fluorescence (APC-A) histogram. Fig. 9D shows a count of the tumor cell population on the red fluorescence (APC-A) histogram.

[0200] Fig. 10 and 11 show exemplary flow cytometry results for a suspension after a separation using a magnetic sorting method. The setup corresponds to example 4 described above.Magnetic microparticles, tumor cells as biological target particles, and healthy cells as other biological particles are stained with streptavidin (Red, APC-A), calcein-blue (BV421-A), and calcein-green (FITC-A), respectively. Fig. 10A shows a result of a gating for the total cell population. Fig. 10B shows a result of a gating for the magnetic microparticles. Fig. 11A shows counts of magnetic microparticles, healthy cells, and tumor cells on a forward scattering (FSC-A) histogram. Fig. 10C shows a result of a gating for the tumor cell population. Fig. 10D shows a result of a gating for the healthy cell population. Fig. 11B shows distribution ratios of tumor cells and healthy cells in the total cell population on a green fluorescence emission (FITC-A) histogram. Fig. 10E shows a distribution of all populations on a scatter contour plot with axes of red fluorescence (APC-A) and green fluorescence (FITC-A) emissions. Fig. 10F shows a distribution of all populations on a scatter contour plot with axes of red fluorescence (APC-A) and blue fluorescence (BV421-A) emissions. Fig. 11C shows a count of the healthy cell population on a red fluorescence (APC-A) histogram. Fig. 11D shows a count of the tumor cell population on the red fluorescence (APC-A) histogram. In comparison with the results in Fig. 8 and 9 before the magnetic selection, the selection and tagging of a majority (80.7%) of the tumor cell population is recognizable by the shift in the APC-A axis of the histograms.

[0201] Fig. 12 illustrates an exemplary separating of biological target particles 142 in a suspension 160 using magnetic microparticles 140 according to the example 5 described above. The biological target particles 142 are tumor cells, e.g., CAPAN-2 pancreatic cells in case of example 5, while other biological particles 146 comprised by the suspension 160 are healthy cells, e.g., BJ fibroblast cells in case of example 5. The magnetic microparticles 140 couple to the tumor cells 152 using target-specific surface coupling elements and the resulting magnetic particle complexes are retained on a surface of a substrate 102 using a magnetic field gradient generated with a magnetic field generator component 120 for the separation process. The scale bars are 50 pm.

[0202] Fig. 13 and 14 show exemplary flow cytometry results for a supernatant cell solution collected from the suspension 160 of Fig. 12. The setup corresponds to example 5 described above. Magnetic microparticles, tumor cells as biological target particles, and healthy cells as other biological particles are stained with streptavidin (Red, APC-A), calcein-blue (BV421-A), andcalcein-green (FITC-A), respectively. Fig. 13A shows a result of a gating for the total cell population. Fig. 13B shows a result of a gating for the active microparticles. Fig. 14A shows counts of the active microparticles, healthy cells, and tumor cells on a forward scattering (FSC-A) histogram. Fig. 13C shows a result of a gating for the tumor cell population. Fig. 13D shows a result of a gating for the healthy cell population. Fig. 14B shows distribution ratios of tumor cells and healthy cells in the total cell population on a green fluorescence emission (FITC-A) histogram. Due to the magnetic separation, a majority of the healthy cell population (79.0%) is collected with a serological pipette. Fig. 13E shows a distribution of all populations on a scatter contour plot with axes of red fluorescence (APC-A) and green fluorescence (FITC-A) emissions. Fig. 13F shows a distribution of all populations on a scatter contour plot with axes of red fluorescence (APC-A) and blue fluorescence (BV421-A) emissions. Fig. 14C shows a count of healthy cell population on a red fluorescence (APC-A) histogram. Fig. 14D shows a count of tumor cell population on the red fluorescence (APC-A) histogram.

[0203] Fig. 15 and 16 show exemplary flow cytometry results for a magnetically collected cell pellet solution of the suspension 160 of Fig. 12. The setup corresponds to example 5 described above. Magnetic microparticles, tumor cells as biological target particles, and healthy cells as other biological particles are stained with streptavidin (Red, APC-A), calcein-blue (BV421-A), and calcein-green (FITC-A), respectively. Fig. 15A shows a result of a gating for the total cell population. Fig. 15B shows a result of a gating for the active microparticles. Fig. 16A shows counts of the active microparticles, healthy cells, and tumor cells on a forward scattering (FSC-A) histogram. Fig. 15C shows a result of a gating for the tumor cell population. Fig. 15D shows a result of a gating for the healthy cell population. Fig. 16B shows distribution ratios of tumor cells and healthy cells in the total cell population on a green fluorescence emission (FITC-A) histogram. Due to the planar magnetic field generation on the surface of the substrate, a majority of the tumor cell population (75.4%) is held in the cell container, i.e., on the substrate. Fig. 15E shows a result of a distribution of all populations on a scatter contour plot with axes of red fluorescence (APC-A) and green fluorescence (FITC-A) emissions. Fig. 15F shows a result of a distribution of all populations on a scatter contour plot with axes of red fluorescence (APC-A) and blue fluorescence (BV421-A) emissions. Fig. 16C shows a count of the healthy cell population on a red fluorescence (APC-A) histogram. Fig. 16D shows a count of the tumor cell population on the red fluorescence (APC-A) histogram.

[0204] Fig. 17 shows an exemplary magnetic sorting method for selectively separating biological target particles from other biological particles within a liquid of a suspension. In block 200, thesuspension is provided. For example, the suspension is provided on a surface of a substrate. In block 202, the suspension is added with magnetic microparticles, which comprise a permanent net magnetic moment. Block 202 may, e.g., be executed after block 200, i.e., after the suspension has been provided. Alternatively, block 202 may, e.g., be executed before block 200 so that the suspension is provided with the magnetic microparticles already added. At least a shell section of each of the magnetic microparticles is applied with target-specific surface coupling elements configured for selectively coupling to a surface of the biological target particles. In block 204, a dynamic magnetic field is applied for actively controlling movements of the magnetic microparticles within the suspension. The applied dynamic magnetic field is configured for inducing the magnetic microparticles to perform translational movements through the suspension and, while moving through the suspension, to couple to the biological target particles via the target-specific surface coupling elements forming magnetic particle complexes. For example, the translational movements of the magnetic microparticles induced by the applied dynamic magnetic field are translational movements along the surface of the substrate. In block 206, the magnetic particle complexes are separated from the other biological particles using the magnetic moment of the magnetic microparticles comprised by the magnetic particle complexes. The separating may, e.g., comprise retaining the magnetic particle complexes on a surface using a magnetic field gradient in a direction perpendicular to the surface. With the magnetic particle complexes and thus the biological target particles retained on the surface, the suspension with the other biological particles may be extracted such that only the magnetic particle complexes remain. Alternatively, the separating may, e.g., comprise using the dynamic magnetic field to move the magnetic particle complexes with the biological target particles to a predefined target area of the suspension, from which the magnetic particle complexes with the biological target particles may be extracted. Thus, only the other biological particles may remain in the suspension.

[0205] Fig. 18 shows an exemplary computer component 120. The computer component 120 may be configured for controlling a magnetic sorting system for selectively separating biological target particles from other biological particles within a liquid of a suspension. The exemplary computer component 120 is shown as comprising a processing unit 122. The processing unit 122 is intended to represent one or more processors or processing cores or other processing components configured for executing computational tasks. The processing unit 122 is shown as being connected to a hardware interface 126 and a memory 124. The hardware interface 126 may enable the processing unit 122 to exchange commands and data with other components,e.g., a magnetic field generator component, a suspension inlet component, a magnetic microparticle inlet component, and / or a separation component of the magnetic sorting system.

[0206] The computer component 120 is further shown as being connected to an optional user interface 128 which may, e.g., enable an operator to control and operate the computer component 120 and via the computer component 120, e.g., the magnetic sorting system. The user interface 128 may, e.g., comprise an output and / or input device enabling the operator to interact with the computer component 120.

[0207] The memory 124 is shown as containing machine-executable instructions 129. The machine-executable instructions 129 enable the processing unit 122 to perform controlling tasks, such as controlling, e.g., a magnetic field generator component, a suspension inlet component, a magnetic microparticle inlet component, and / or a separation component of the magnetic sorting system, to perform numerical tasks, as well as performing various signal data processing tasks. The machine-executable instructions 129 may, e.g., enable the processing unit 122 and thus the computer component 120 to execute the methods of Fig. 17.

[0208] The execution of the machine executable instructions 129 may, e.g., cause the computer component 120 to control the suspension inlet component to provide the suspension. The suspension inlet component may, e.g., be controlled to provide the suspension on a surface of a substrate. The suspension is added with magnetic microparticles. For example, a magnetic microparticle inlet component may be controlled by the computer component 120 to add the magnetic microparticles to the suspension. The magnetic microparticles comprise a permanent net magnetic moment. At least a shell section of each of the magnetic microparticles is applied with target-specific surface coupling elements configured for selectively coupling to a surface of the biological target particles. The magnetic field generator component is controlled by the computer component 120 to apply a dynamic magnetic field for actively controlling movements of the magnetic microparticles within the suspension. The applied dynamic magnetic field is configured for inducing the magnetic microparticles to perform translational movements through the suspension and, while moving through the suspension, to couple to the biological target particles via the target-specific surface coupling elements forming magnetic particle complexes. The magnetic field generator component may, e.g., be controlled to apply a dynamic magnetic field configured for inducing the translational movements of the magnetic microparticles along the surface of the substrate. The magnetic field generator component may further be controlled by the computer component 120 to separate the magnetic particle complexes from the other biological particles using the magnetic moment of the magnetic microparticles comprised by themagnetic particle complexes. For example, further an extraction component may be controlled by the computer component 120 to extract the magnetic particle complexes and / or the other biological particles from the suspension.

[0209] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed examples.

[0210] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

[0211] A single processor or other unit may fulfill the functions of several items recited in the claims. A computer program may be stored / distributed on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.

[0212] As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as an apparatus, method, computer program, or computer program product.Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro¬ code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a "circuit," "module" or "system." Furthermore, aspects of the present invention may take the form of a computer program product embodied in one or more computer readable medium(s) having computer executable code embodied thereon. A computer program comprises the computer executable code or "program instructions".

[0213] Any combination of one or more computer readable medium(s) may be utilized. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A "computer-readable storage medium" as used herein encompasses any tangible storage medium which may store instructions which are executable by a processor of a computer component. The computer-readable storage medium may be referred to as acomputer-readable non-transitory storage medium. The computer-readable storage medium may also be referred to as a tangible computer readable medium. For example, a computer- readable storage medium may also be able to store data which is able to be accessed by the processor of the computer component. Examples of computer-readable storage media include, but are not limited to: a floppy disk, a magnetic hard disk drive, a solid-state hard disk, flash memory, a USB thumb drive, Random Access Memory (RAM), Read Only Memory (ROM), an optical disk, a magneto-optical disk, and the register file of the processor. Examples of optical disks include Compact Disks (CD) and Digital Versatile Disks (DVD), for example CD-ROM, CD-RW, CD-R, DVD-ROM, DVD-RW, or DVD-R disks. A further example of an optical disk may be a Blu-ray disk. The term computer readable-storage medium also refers to various types of recording media capable of being accessed by the computer component via a network or communication link. For example, data may be retrieved over a modem, over the Internet, or over a local area network. Computer executable code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0214] A computer readable signal medium may include a propagated data signal with computer executable code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electromagnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

[0215] "Computer memory", "memory unit", or "memory" is an example of a computer- readable storage medium. Computer memory is any memory which is directly accessible to a processing unit. "Computer storage" or "storage" is a further example of a computer-readable storage medium. Computer storage is any non-volatile computer-readable storage medium. For example, computer storage may also be computer memory or vice versa.

[0216] A "processing unit" or "processor" as used herein encompasses an electronic component which is able to execute a program or machine executable instruction or computer executable code. References to the computer component comprising "a processing unit" should be interpreted as possibly containing more than one processor or processing core. The processor may for instance be a multi-core processor. A processor may also refer to a collection of processors within a single computer component or distributed amongst multiple computercomponents. The term computer component should also be interpreted to possibly refer to a collection or network of computer components each comprising a processing unit, e.g., a processor or processors. The computer executable code may be executed by multiple processors that may be within the same computer component or which may even be distributed across multiple computer components.

[0217] Computer executable code may comprise machine executable instructions or a program which causes a processor to perform an aspect of the present invention. Computer executable code for carrying out operations for aspects of the present invention may be written in any combination of one or more programming languages, including an object-oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages and compiled into machine executable instructions. In some instances, the computer executable code may be in the form of a high-level language or in a pre-compiled form and be used in conjunction with an interpreter which generates the machine executable instructions on the fly.

[0218] The computer executable code may execute entirely on a user's computer component, partly on the user's computer component, as a stand-alone software package, partly on the user's computer component and partly on a remote computer component or entirely on the remote computer component or server. In the latter scenario, the computer component may be connected to the user's computer component through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0219] Generally, the program instructions can be executed on one processor or on several processors. In the case of multiple processors, they can be distributed over several different entities like clients, servers, etc. Each processor could execute a portion of the instructions intended for that entity. Thus, when referring to a system or process involving multiple entities, the computer program or program instructions are understood to be adapted to be executed by a processor associated or related to the respective entity.

[0220] A "user interface" as used herein is an interface which allows a user or operator to interact with a computer or computer component. A "user interface" may also be referred to as a "human interface device". A user interface may provide information or data to the operator and / or receive information or data from the operator. A user interface may enable input from an operator to be received by the computer component and may provide output to the user fromthe computer component. In other words, the user interface may allow an operator to control or manipulate a computer component and the interface may allow the computer component to indicate the effects of the operator's control or manipulation. The display of data or information on a display or a graphical user interface is an example of providing information to an operator. The receiving of data through a keyboard, mouse, trackball, touchpad, pointing stick, graphics tablet, joystick, gamepad, webcam, headset, gear sticks, steering wheel, pedals, wired glove, dance pad, remote control, one or more switches, one or more buttons, and accelerometer are all examples of user interface components which enable the receiving of information or data from an operator.

[0221] A GUI element is a data object some of whose attributes specify the shape, layout and / or behavior of an area displayed on a graphical user interface, e.g., a screen. A GUI element can be a standard GUI element such as a button, a text box, a tab, an icon, a text field, a pane, a check-box item or item group or the like. A GUI element can likewise be an image, an alphanumeric character or any combination thereof. At least some of the properties of the displayed GUI elements depend on the data value aggregated on the group of data object said GUI element represents.

[0222] Aspects of the present invention are described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems) and computer program products. It will be understood that each block or a portion of the blocks of the flowchart, illustrations, and / or block diagrams, can be implemented by computer program instructions in form of computer executable code when applicable. It is further understood that, when not mutually exclusive, combinations of blocks in different flowcharts, illustrations, and / or block diagrams may be combined. These computer program instructions may be provided to a processing unit of a computer component, e.g., a general-purpose computer, a special-purpose computer, or another other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0223] These computer program instructions may also be stored in a computer readable medium that can direct a computer component, i.e., a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufactureincluding instructions which implement the function / act specified in the flowchart and / or block diagram block or blocks.

[0224] The computer program instructions may also be loaded onto a computer component, i.e., a computer, other programmable data processing apparatus, or other devices, to cause a series of operational steps to be performed on the computer component, i.e., the computer, other programmable apparatus or other devices, to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.REFERENCE SIGNS LIST100 magnetic sorting system102 substrate104 suspension inlet component106 magnetic microparticle inlet component 108 magnetic field generator component 110 sorted particle outlet component112 residue outlet component120 computer component122 processing unit124 memory126 hardware interface128 user interface129 machine-executable instructions140 magnetic microparticle142 biological target particle144 magnetic particle complex146 other biological particle150 path160 suspension170 first shell section172 second shell section180 pre-magnetized ferromagnetic component 182 magnetization direction184 cross-section186 base body188 passivation layer190 target-specific surface coupling element

Claims

CLAIMS1. A magnetic sorting method for selectively separating biological target particles (142) from other biological particles (146) within a liquid of a suspension (160), the method comprising: providing the suspension (160), the suspension (160) being added with magnetic microparticles (140), the magnetic microparticles (140) comprising a permanent net magnetic moment, at least a shell section (170) of each of the magnetic microparticles (140) being applied with target-specific surface coupling elements (190) configured for selectively coupling to a surface of the biological target particles (142);applying a dynamic magnetic field for actively controlling movements of the magnetic microparticles (140) within the suspension (160), the applied dynamic magnetic field being configured for inducing the magnetic microparticles (140) to perform translational movements through the suspension (160) and, while moving through the suspension (160), to couple to the biological target particles (142) via the target-specific surface coupling elements (190) forming magnetic particle complexes (144);separating the magnetic particle complexes (144) from the other biological particles (146) using the magnetic moment of the magnetic microparticles (140) comprised by the magnetic particle complexes (144).

2. The method of claim 1, the separating comprising retaining the magnetic particle complexes (144) on a surface using a magnetic field gradient in a direction perpendicular to the surface.

3. The method of any of the previous claims, the separating comprising using the dynamic magnetic field to move the magnetic particle complexes (144) to a predefined target area of the suspension (160).

4. The method of claim 3, the separating further comprising extracting the magnetic particle complexes (144) from the suspension (160) from the predefined target area.

5. The method of any of the previous claims, the separating further comprising extracting the other biological particles (146) from the suspension (160).

6. The method of any of the previous claims, the dynamic magnetic field comprising a rotating magnetic field causing rotations of the magnetic microparticles (140), the rotations of the magnetic microparticles (140) resulting in the translational movements of the magnetic microparticles (140).

7. The method of claim 6, the magnetic microparticles (140) rotating with a rotational frequency of 1 Hz to 50 Hz, preferably of 5 Hz to 20 Hz, and more preferably of 10 Hz to 15 Hz.

8. The method of any of the previous claims, the magnetic microparticles (140) being spherical particles.

9. The method of any of the previous claims, the magnetic microparticles (140) having a diameter of 1 pm to 8 pm, preferably of 1.5 pm to 3 pm, and more preferably of 1.75 pm to 2.25 pm.

10. The method of any of the previous claims, the magnetic microparticles (140) having a surface-to-volume ratio of 3 to 0.3, preferably of 2 to 1, more preferably of 1.75 to 1.25.

11. The method of any of the previous claims, the magnetic microparticles (140) comprising a pre-magnetized ferromagnetic component (180) providing the permanent net magnetic moment of the magnetic microparticles (140).

12. The method of claim 11, the magnetic microparticles (140) being magnetic Janus microparticles comprising a first shell section (170) and a second shell section (172), which is different from the first shell section (170), the first shell section (170) comprising the premagnetized ferromagnetic component (180), the second shell section (172) comprising the target-specific surface coupling elements (190).

13. The method of any of the previous claims, the magnetic microparticles (140) forming paramagnetic and / or superparamagnetic chains.

14. The method of any of the previous claims, the translational movements of the magnetic microparticles (140) breaking a diffusion limit for particle movements within the suspension (160).

15. The method of any of the previous claims, the method further comprising controlling the dynamic magnetic field for controlling the translational movements of the magnetic microparticles (140) along a predefined path (150).

16. The method of any of the previous claims, the suspension (160) being provided on a surface of a substrate (102) and the translational movements of the magnetic microparticles (140) induced by the applied dynamic magnetic field being translational movements along the surface of the substrate (102).

17. The method of claim 16, the dynamic magnetic field extending across the complete surface of the substrate (102), the translational movements of the magnetic microparticles (140) extending across the complete surface of the substrate (102).

18. The method of any of claims 16 to 17, the surface of the substrate (102) being a nonadhesive surface with respect to the biological target particles (142).

19. The method of claim 18, the non-adhesive surface comprising one or more of the following: poly-HEMA, polyethylene glycol, polytetrafluoroethylene, a hydrophilic polymer brush, a silicone-based anti-fouling coating, zwitterionic polymers, a superhydrophobic surface, polyethylene oxide, a fluoropolymer coating, amphiphilic block copolymer.

20. The method of any of claims 16 to 19, the substrate (102) being provided by one of the following: a Petri dish, a microfluidic chip, a cartridge.

21. The method of any of the previous claims, the target-specific surface coupling elements (190) comprising one or more of the following: surface characteristics, targeting moieties.

22. The method of claim 21, the targeting moieties comprising one or more of the following: antibodies, aptamers, ligands, peptides, molecules, carbohydrates, glycoproteins, glycolipids, nanobodies, adhesion molecules, metabolic markers.

23. The method of any of the previous claims, the biological target particles (142) comprising one or more of the following types of biological particles: cells, subcellular components, microorganisms, multicellular structures, cell-derived structures, genetically modified biological microentities, phenotypically modified biological microentities, and / orthe other biological particles (146) comprising one or more of the following types of biological particles: cells, subcellular components, microorganisms, multicellular structures, cell-derived structures, genetically modified biological microentities, phenotypically modified biological microentities.

24. The method of any of the previous claims, the method further comprising analyzing the biological target particles (142) and / or the other biological particles (146) after the separating, optionally using one or more of the following analyzing techniques: flow cytometry, microscopy, molecular and / or immunological assays, proteins, or other biomolecules, western blotting, mass spectrometry, single-cell RNA sequencing.

25. A computer program for controlling a magnetic sorting system (100) for selectively separating biological target particles (142) from other biological particles (146) within a liquid of a suspension (160),the magnetic sorting system (100) comprising a suspension inlet component (104), a magnetic field generator component (108), a separation component, and a computer component (120),the computer program comprising machine executable instructions (129) for an execution by the computer component, wherein the execution of the machine executable instructions (129) causes the computer component (120) to control the magnetic sorting system (100) to perform a method comprising:controlling the suspension inlet component (104) to provide the suspension (160), the suspension (160) being added with magnetic microparticles (140), the magnetic microparticles (140) comprising a permanent net magnetic moment, at least a shell section (170) of each of the magnetic microparticles (140) being applied with target-specific surface coupling elements (190) configured for selectively coupling to a surface of the biological target particles (142);controlling the magnetic field generator component (108) to apply a dynamic magnetic field for actively controlling movements of the magnetic microparticles (140) within the suspension (160), the applied dynamic magnetic field being configured for inducing the magnetic microparticles (140) to perform translational movements through the suspension (160) and, while moving through the suspension (160), to couple to the biological target particles (142) via the target-specific surface coupling elements (190) forming magnetic particle complexes (144);controlling the magnetic field generator component (108) to separate the magnetic particle complexes (144) from the other biological particles (146) using the magnetic moment of the magnetic microparticles (140) comprised by the magnetic particle complexes (144).

26. A computer component (120) for controlling a magnetic sorting system (100) for selectively separating biological target particles (142) from other biological particles (146) within a liquid of a suspension (160),the magnetic sorting system (100) comprising a suspension inlet component (104), a magnetic field generator component (108), and a separation component,the computer component (120) comprising a memory (124) with machine executable instructions (129) stored therein for an execution by the computer component, wherein the execution of the machine executable instructions (129) causes the computer component (120) to control the magnetic sorting system (100) to perform a method comprising:controlling the suspension inlet component (104) to provide the suspension (160), the suspension (160) being added with magnetic microparticles (140), the magnetic microparticles (140) comprising a permanent net magnetic moment, at least a shell section (170) of each of the magnetic microparticles (140) being applied with target-specific surface coupling elements (190) configured for selectively coupling to a surface of the biological target particles (142);controlling the magnetic field generator component (108) to apply a dynamic magnetic field for actively controlling movements of the magnetic microparticles (140) within the suspension (160), the applied dynamic magnetic field being configured for inducing the magnetic microparticles (140) to perform translational movements through the suspension (160) and, while moving through the suspension (160), to couple to the biological target particles (142) via the target-specific surface coupling elements (190) forming magnetic particle complexes (144);controlling the magnetic field generator component (108) to separate the magnetic particle complexes (144) from the other biological particles (146) using the magnetic moment of the magnetic microparticles (140) comprised by the magnetic particle complexes (144).

27. A magnetic sorting system (100) for selectively separating biological target particles (142) from other biological particles (146) within a liquid of a suspension (160), the magnetic sorting system (100) comprising a suspension inlet component (104), a magnetic field generator component (108), a separation component, and the computer component (120) of claim 26.

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