Off-Chip Pulsed Magnetic Field for Biosensor Clustering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing magnetic biosensors face challenges in achieving accurate detection of magnetic particles due to undesired clustering and variability in sensor signals, which affects the reliability of magnetic particle detection and separation.
Innovation Solution
The implementation of a pulsed magnetic actuation method, where a time-dependent magnetic field is generated off the substrate to guide magnetic particles, preventing clustering and improving detection accuracy by controlling the interaction between magnetic particles and the sensor surface, allowing for efficient washing and binding processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a magnetic field generator is integrated on the substrate for generating AC magnetic field, then the device structure is compact and easy to manufacture, but clustering of magnetic particles occurs and measurement accuracy deteriorates
Solution Approach 1:
The magnetic field generator is extracted from the substrate integration and positioned as a separate off-chip component. This separation prevents the generator from causing clustering of magnetic particles on the sensor surface, thereby maintaining measurement accuracy while the device remains compact through external positioning of the generator.
Solution Approach 2:
The patent employs periodic pulsed magnetic fields instead of continuous AC magnetic fields. The pulsed nature of the magnetic field prevents constant clustering of magnetic particles while still enabling effective guidance and actuation during active periods, thus maintaining detection accuracy.
2Speed
If continuous magnetic field actuation is applied to guide magnetic particles, then particle guidance is effective, but particle clustering increases and sensor signal variability worsens
Solution Approach 1:
The patent uses periodic pulsed magnetic fields to guide magnetic particles. During the pulsed active periods, particles are effectively guided and actuated. During the off-periods, the magnetic field is turned off, preventing continuous clustering and allowing particle relaxation, thus maintaining signal stability and reliability.
Solution Approach 2:
The magnetic field actuation is made dynamic through pulsing rather than static continuous application. This dynamic control allows the system to switch between high-guidance-mode (during pulses) and low-clustering-mode (during off-periods), optimizing both particle guidance efficiency and signal stability.
3Productivity
If magnetic particles are allowed to bind to sensor surface during actuation, then detection speed increases, but clustering prevents accurate binding
Solution Approach 1:
The pulsed magnetic field allows magnetic particles to bind to the sensor surface during active pulsed periods, increasing detection speed. During the off-periods, the field is turned off, preventing forced clustering and allowing particles to bind accurately based on specific interactions rather than magnetic aggregation, thus maintaining binding accuracy.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances the accuracy and speed of magnetic particle detection, reduces clustering, and improves the efficiency of the biosensor by allowing all magnetic particles to bind to the sensor surface during actuation, facilitating faster washing and kinetic measurements without delaying the assay.
Implementation Method 1
a magnetic field control unit provided off the substrate (that is to say apart from the substrate, or outside of the substrate, particularly without contact to the substrate) and being adapted for generating a time-dependent magnetic field for interaction with the magnetic particles, particularly for guiding the magnetic particles with respect to the substrate and/or with respect to the sensing unit
Implementation Method 2
a sensing unit provided on and/or in and/or near (for instance coupled to or connected to) the substrate and being adapted for sensing a detection signal indicative of the presence of the magnetic particles
Data Source
AI summary
A sensor device for sensing magnetic particles, the sensor device including a substrate and a sensing unit provided on and/or in and/or near the substrate. The sensing unit is configured to sense a detection signal indicative of the presence of the magnetic particles. The sensor device further includes a magnetic field control unit which may be provided off the substrate and is configured to generate a time-dependent magnetic field for interaction with the magnetic particles.