213 results about "Circulating cancer cell" patented technology

The invention discloses a fluorescent colorimetric sensor for detecting circulating tumor cells and a preparation method of the fluorescent colorimetric sensor. The preparation method comprises the following steps: S4, adding a prepared detection antibody modified with horse radish peroxidase and used for detecting the circulating tumor cells, and incubating; s5, adding a Tris buffer solution and a H2O2 solution, and incubating; s6, preparing an EuMOF nanoflower solution; and S7, adding the EuMOF nanoflower solution and 3, 3 ', 5, 5'-tetramethyl benzidine to react, detecting the fluorescence intensity in the presence of circulating tumor cells with different concentrations by using a luminoscope, detecting the ultraviolet absorbance value in the presence of circulating tumor cells with different concentrations by using a multifunctional microplate reader, and constructing a fluorescence intensity-concentration working curve and an ultraviolet absorbance value-concentration working curve. The method is used for qualitative and quantitative analysis and detection of the circulating tumor cells, realizes bimodal signal response to the circulating tumor cells, and has high sensitivity and simplicity and convenience in operation.

The invention relates to the technical field of biomedical engineering and microfluidics, in particular to a fluid dynamics topological optimization design method of a circulating tumor cell sorting structure, which comprises the following steps of: establishing a three-dimensional flow field model containing a key separation area in a preset design domain, dispersing by adopting a tetrahedral mesh and setting boundary conditions; the method comprises the following steps: establishing a multi-objective optimization function based on a maximized transverse focusing distance, a minimum shear force peak value and a total pressure drop, dispersing a design domain into units and endowing the units with density variables, and realizing global automatic topological optimization by adopting penalty material interpolation and minimum flow velocity threshold constraint. An optimization result is subjected to structural reconstruction processing to generate a CAD model adaptive to micro-nano machining, closed-loop feedback is formed through secondary verification and experimental verification of computational fluid mechanics, it is ensured that the design meets the requirements for sorting efficiency and cell activity, limitation of a traditional flow channel form is broken through, and the design freedom degree, manufacturability and application value are improved.

The invention belongs to the technical field of biological intelligent detection, and particularly relates to a circulating tumor cell automatic detection device based on a micro-fluidic nano chip and AI analysis and application. The device comprises a micro-fluidic chip module, an optical acquisition module, an image recognition module, a feedback control module and a liquid path control module, and can realize efficient enrichment, image recognition and dynamic fluidic regulation of circulating tumor cells in peripheral blood. By constructing a change trend model of an image frame sequence, cell state changes are recognized in real time, flow velocity and channel control instructions are output, and collaborative optimization of recognition precision and the sample utilization rate is achieved. The device is suitable for tumor early screening, curative effect monitoring and recurrence early warning scenes.

The invention relates to the technical field of medical information, and particularly discloses a blood transfusion strategy optimization system based on clinical indexes and molecular markers, which comprises the following steps: firstly, collecting clinical indexes of a patient and molecular marker data derived from circulating tumor cells; standardized integration is carried out to construct a multi-dimensional feature set reflecting correlation between clinical dynamics and molecular features; key association rules are identified through data mining, quantitative abnormal expression profiles and risk hierarchical labels are generated for each patient according to the key association rules, the blood transfusion urgency state is evaluated in combination with real-time data, physiological responses and risk changes under different blood transfusion schemes are deduced, and the optimal individual blood transfusion strategy parameters are solved. Performing deduction verification on the strategy by constructing a patient-specific virtual simulation scene, comparing the strategy with historical data to calculate an expected efficiency deviation degree, and outputting a final execution scheme subjected to optimization verification; according to the invention, the transformation from static threshold transfusion to individualized dynamic prediction and optimized transfusion is realized.

The invention discloses a precise liquid treatment system and method based on a multi-channel liquid separation valve and gas replacement, and belongs to the technical field of biomedical detection equipment. The system comprises a multi-channel liquid distribution valve and an intelligent control system, the liquid distribution valve is provided with a plurality of channels which are respectively connected with four groups of coloring agent bottles, sheath liquid bottles, waste liquid bottles and gas bottles; a liquid level detection sensor is arranged between the liquid distribution valve and the peristaltic pump, and an outlet of the peristaltic pump is communicated with the dyeing pool. The method comprises the steps of cancer cell acquisition, fixed permeation treatment, system pre-filling, multiple fluorescent staining and fluorescent imaging. High-precision distribution of micro-liquid is realized through cooperative control of liquid separation valve channel switching and inert gas replacement, and high-precision and high-repeatability distribution of micro-upgrading liquid can be realized; a gas isolation mechanism significantly reduces the risk of cross contamination, multi-channel parallel processing improves the detection efficiency, and the device is suitable for circulating tumor cell multi-staining, flow analysis and other biomedical scenes needing high-precision liquid treatment.

The invention belongs to the technical field of pharmaceutical preparations. The invention discloses a multifunctional bionic nano preparation, a preparation method and application. According to the multifunctional bionic nano preparation, the ginsenoside Rg3 has the dual functions of a medicine and a membrane stabilizer, the platelet membrane has the natural targeting capability on circulating tumor cells and metastases, and meanwhile, the cationic liposome is used for adsorbing negatively-charged NETs nucleic acid protein compounds, so that potential reversal and active targeting are achieved, and the multifunctional bionic nano preparation has a good application prospect. And by co-carrying paclitaxel (PTX) and a photothermal agent (PCP) and integrating photothermal-chemotherapy-immunogenic death (ICD) induction functions, the tumor-related fibroblast activation can be effectively inhibited, circulating tumor cells can be efficiently captured, a tumor immune microenvironment can be remodeled, the tumor cells can be effectively killed, and tumor distal metastasis can be inhibited.

The invention discloses a circulating tumor cell detection and analysis device, and belongs to the field of cell detection. A circulating tumor cell detection and analysis device comprises a box body, a sample tube, a mixing device and a glass slide area, an operation panel and a PLC are arranged on the front face of the box body, the sample tube, the mixing device and the glass slide area are arranged in the box body, a circulating tumor cell detection system A is further arranged in the box body, and a dyeing quality monitoring system B is arranged on the mixing device. The problem that the detection result is not accurate and stable enough due to limitation in the prior art is solved, various characteristics of the circulating tumor cells can be accurately recognized by collecting the images and performing a series of operations in cooperation with the deep learning target detection network, a reliable basis is provided for diagnosis, and the detection efficiency is improved. By monitoring the fluorescence signal, the temperature, the pH value and the like in real time, the dyeing quality can be strictly controlled, the reliability of the detection result is ensured, and misdiagnosis caused by the dyeing problem is avoided.

The invention relates to the technical field of computational fluid mechanics and biological microfluidic design, in particular to a model order reduction method for rapid optimization of a circulating tumor cell (CTC) sorting structure, which comprises the following steps of: constructing a three-dimensional full-order computational fluid mechanics model by collecting channel geometric structure parameters and fluid working condition parameters, and generating a training data set; organizing a flow field snapshot into a matrix form, extracting a dominant mode, constructing a low-dimensional modal space by taking the dominant mode as a base vector, establishing a low-dimensional ordinary differential model through Galerkin projection, and training a parameter-modal coefficient mapping relation by adopting a deep neural network to form a complete reduced-order model; and finally, constructing a multi-objective optimization problem based on the reduced-order model, carrying out optimization iteration by adopting an evolutionary algorithm, and returning an optimization result to the full-order model for verification, so that rapid optimization design of the CTC sorting structure is realized, and an effective solution is provided for intelligent design of a biomedical microfluidic device.

The invention relates to the technical field of biological detection, and discloses a method for double-ring detection of lung cancer L858R mutation based on CRISPR / Cas9 and DNA, and the method comprises the following steps: enriching circulating tumor cells CTC from a blood sample; extracting genomic DNA (deoxyribonucleic acid) of the enriched CTC; carrying out amplification on the DNA fragment containing the L858R mutation by adopting recombinase polymerase amplification RPA (recombinase polymerase amplification); the amplified DNA fragment is hybridized with a recognition ring in a DNA double-ring structure, a DNA double ring is composed of the recognition ring and a report ring, and a part of region of the recognition ring is hybridized with a corresponding fragment of the report ring to form a staggered double-chain region; when L858R mutation exists, the mutated DNA and a recognition ring are hybridized to activate a CRISPR / Cas9 system, and under the guidance of sgRNA, Cas9 cuts hybrid double strands and releases a report ring; carrying out rolling circle amplification RCA under the action of DNA polymerase by taking the released report ring as a template; a fluorescent probe is used for detecting an RCA amplification product, and whether L858R mutation exists or not is judged according to a fluorescence signal. The CRISPR / Cas9 system is combined with a DNA double-ring structure, so that the ultra-sensitive and specific detection on the lung cancer L858R mutation is realized.

The invention relates to a circulating tumor cell enrichment, separation and dyeing integrated system and application thereof.The circulating tumor cell enrichment, separation and dyeing integrated system is composed of a bottom plate module, a platform module, a multi-pipette module, a power module and a shell module; the platform module comprises a sample tube rotating and uniformly mixing module, a magnetic adsorption module, a reagent module, a waste liquid pool module and a gun head module, and the sample tube rotating and uniformly mixing module, the magnetic adsorption module and the reagent module are fixedly mounted on a bottom plate I in sequence. The CTC separation and dyeing integrated system is developed on the basis of the immunomagnetic bead technology, enrichment separation and immunofluorescent dyeing of CTC can be automatically completed by running a program, manual operation errors are effectively avoided through a programmed process, and the CTC separation and dyeing integrated system is particularly suitable for clinical CTC detection. The system is also suitable for other enrichment and separation applications based on an immunomagnetic bead technology, including but not limited to enrichment and separation of biological macromolecules such as cells, exosomes, proteins and the like.

The present invention relates to a circulating tumor cell detection system and an electrochemical sensor preparation method, which relate to the field of computer vision. The system includes an acquisition module for acquiring cell images using an electrochemical sensor; a segmentation and extraction module for performing segmentation and extraction based on the cell images using a cell image segmentation model to obtain segmentation results; the cell image segmentation model is obtained by training a U-Net network using a transfer learning algorithm; and a Grad-CAM algorithm processing module for obtaining a tumor cell heat map based on the segmentation results using the Grad-CAM algorithm. The present invention can achieve accurate identification of CTCs.

This invention relates to a method and application for enriching circulating tumor cells (CTCs) based on ambient temperature mechanical perfusion technology, belonging to the field of biomedical technology. The method comprises the following steps: flushing the liver resected during liver transplantation via the portal vein and hepatic artery, connecting it to an ambient temperature mechanical perfusion loop, and performing in vitro perfusion using simulated blood perfusion fluid; when perfusion exceeds 2 hours and the lactate content drops to <5 mmol / L, collecting the simulated blood perfusion fluid; and sequentially subjecting the simulated blood perfusion fluid to centrifugation, red blood cell removal, and white blood cell removal to obtain enriched circulating tumor cells (CTCs) for liver cancer. A human liver cancer ex vivo organ perfusion model is constructed using NMP technology to fully recreate the tumor microenvironment and CTC generation process, and the large volume of perfusion fluid is processed to achieve efficient enrichment of CTCs.

This invention belongs to the field of biomedicine and specifically relates to a method and kit for enriching circulating tumor cells (CTCs) in liver cancer using GPC3 in combination with MERTK. This method combines MERTK with traditional markers such as EpCAM, vimentin, and GPC3 to capture circulating tumor cells in liver cancer, achieving improved enrichment of CTCs. This method and its accompanying kit are widely applicable to early screening of liver cancer, postoperative recurrence monitoring, metastasis risk assessment, and personalized treatment management, and has promising prospects for clinical translation.

The invention relates to the technical field of medical adsorbents for blood perfusion, and discloses an application of a trans-cyclooctene group adsorbent based on a biological orthogonal reaction in preparation of a circulating tumor cell clearing preparation. The adsorbent adopts sephadex microspheres as a carrier, the surface of the carrier is modified with a trans-cyclooctene (TCO) group, a tetrazine (Tz) group is taken in by CTCs through modified mannose, the Tz group is expressed on the surface of a CTCs cell membrane in the form of glycoprotein through a Roseman-Warden pathway in cells, TCO and Tz are subjected to a biological orthogonal reaction specifically, and the adsorption capacity of the adsorbent is improved. The sephadex microsphere adsorbent can effectively enrich and remove CTCs in blood of the whole body of a patient through adsorption, and compared with a conventional single-antibody or multi-antibody capture technology, the sephadex microsphere adsorbent does not depend on antibody-antigen binding, and the capture efficiency of the CTCs can be remarkably improved through a biological orthogonal reaction.

The utility model discloses a kind of circulating tumor cell in vitro culture fluid filtering devices, including shell, the bottom surface of the shell is fixedly installed with rotating motor, the inner bottom wall of the shell is inlayed with first bearing, the inner ring of the first bearing is fixedly connected with rotating rod, the output end of the rotating motor is connected with the bottom end of rotating rod by first bearing, the upper surface of the rotating rod is fixedly connected with clamping block. The cooperation of the device through clamping groove and clamping block, realize rotating motor and filter frame flexible separation, by inserting the insert block of cover plate bottom into storage groove, and using positioning assembly to position cover plate, make synchronous assembly extrude filter frame, the phenomenon of displacement occurs when filter frame rotates, realize that filter frame is conveniently disassembled and installed, to facilitate subsequent maintenance and cleaning, to solve the disassembly of the filter screen of existing device is more cumbersome, leading to the problem of lower work efficiency.

The invention discloses automatic imaging equipment for circulating tumor cells, belongs to the technical field of cell imaging, and aims to solve the problems that an electric Z-axis module is easy to generate mechanical wear and affects the positioning accuracy after being used for a long time, the automatic imaging equipment comprises a shell, a camera is mounted in the shell, and an electric optical filter rotating wheel is mounted in the shell; the camera is connected with the electric light filter rotating wheel, a fluorescence imaging light path is installed in the shell and connected with the electric light filter rotating wheel, and a fluorescence illumination light path is fixedly connected to the top of the fluorescence imaging light path. And meanwhile, the situation that abrasion of the two first threaded plates is aggravated due to too many blocks is avoided, the two first threaded plates are directly replaced by the two second threaded plates for use conveniently, and the situation that the positioning precision in the Z-axis direction is affected due to excessive abrasion of the two first threaded plates is avoided.

The invention belongs to the technical field of anti-tumor drugs, and particularly relates to a flexible drug-loaded cell microparticle capable of efficiently targeting tumors and a preparation method of the flexible drug-loaded cell microparticle. Comprising tumor cell-derived drug-loaded microparticles coated with chemotherapeutic drugs, and a flexible regulator modified on the surfaces of the tumor cell-derived drug-loaded microparticles, the flexible regulator comprises a saponin compound and / or a steroid compound, and can regulate and control the hardness of the tumor cell-derived drug-loaded microparticles. The tumor cell-derived drug-loaded microparticles are modified, so that the enrichment and deep penetration of the drug-loaded microparticles in tumor tissues can be remarkably improved, and the efficient targeted delivery of the tumor tissues is realized. Meanwhile, efficient uptake of tumor stem cells to the medicine is promoted, targeted killing is achieved, the tumor stem cells are effectively removed, and tumor growth is remarkably inhibited. In addition, circulating tumor cells can be efficiently targeted, accurate delivery of tumor metastasis is achieved, and tumor metastasis is remarkably inhibited by inhibiting migration and invasion of tumor cells and reducing formation of lung metastasis.

The application provides a kind of bacterial outer membrane vesicle based on acid-sensitive peptide label and its preparation method and application, it is related to the technical field of engineered bacterial outer membrane vesicle.The ClyA-pHLIP fusion protein is designed and synthesized in the application, and the pHA-W3110OMV stably expressing the ClyA-pHLIP fusion protein is successfully obtained by using genetic engineering technology.The pHA-W3110OMV effectively solves the problem of easy aggregation of pHLIP in acidic environment, has good stability and solubility, and provides conditions for the stable targeting performance of pHLIP.Meanwhile, the pHA-W3110OMV not only retains the characteristics of targeting tumor cells in acidic environment, but also realizes the characteristics of targeting tumor cells in non-acidic environment.The pHA-W3110OMV has high targeting tracing efficiency on tumor cells under different pH conditions, and can realize qualitative and quantitative detection of tumor cells in peripheral blood, and has application potential in circulating tumor cell detection and tumor primary and metastasis localization.

The invention relates to the technical field of circulating tumor cell enrichment and automation equipment, in particular to an automatic circulating tumor cell enrichment device. A rectangular disc, a rectangular rod, a placement disc, a chip storage box, a waste liquid outlet pipe, a cover plate, a reagent storage unit, a waste liquid transfer pipe and a waste liquid storage box are arranged; by rotating the rectangular disc at each rotation degree, each chip storage box on the placement disc can directly face a worker to facilitate placement of chips, but the closed opening of the chip storage box closest to the transfer frame does not directly face the worker and is to be subsequently rotated to directly face the worker, so that the chips are placed in each chip storage unit, and the chip placement efficiency is improved. After all the chips are placed, a stepping motor is started, the stepping motor enables a rectangular disc to rotate intermittently, and then the cleaning liquid or the actual liquid in the chip storage box is vibrated to be used for fully conducting cleaning or enrichment reaction on the chips in the chip storage box; according to the invention, one-time enrichment can be carried out on at least fifty chips at one time.

The invention discloses a preparation method and application of a low-field nuclear magnetic resonance sensor for detecting circulating tumor cells based on biological orthogonal chemistry and click chemistry. The preparation method is characterized by comprising the following steps: 1) preparing Fe3O4 (at) Apt; (2) preparing Cys-GO coated CuO; and (3) preparing the LF-NMR biosensor. The Apt specificity is used for identifying mucoprotein (MUC1), so that targeted capture and enrichment of CTC are realized; oxidizing cell membrane sialic acid through NaIO4 to generate an aldehyde group, and triggering a thiazolidine chemical bond to be covalently coupled with sulfydryl / amino of the Cys-GO-coated CuO nano probe; cu < + > released by acidolysis-reduction catalyzes azide and alkyne cycloaddition click reaction, and sol-gel phase transformation is driven. According to the method, the intensity of T2 under the condition of CTC with different concentrations is measured, and a quantitative relation between the CTC concentration and delta T2 is established, so that the CTC in an unknown sample is measured, and the method has the advantages of high selectivity and high sensitivity.

This invention belongs to the field of cell sample detection and provides a microfluidic chip for separating circulating tumor cells (CTCs) based on size and aptamers. The invention includes a functional layer with a sample outlet and a sample inlet, and a cell substrate disposed on the upper and lower surfaces of the functional layer. The sample outlet and sample inlet of the functional layer are connected by a separation channel, which includes at least one micropillar array capable of carrying an EpCAM aptamer. The micropillar array is composed of a capture channel surrounding at least two micropillar structures. One end of the micropillar array is connected to the sample inlet, and the other end of the micropillar array has a gradient retention channel connected to the sample outlet. The microfluidic chip uses EpCAM aptamers to modify the micropillar array, increasing the number of collisions between CTCs and the chip, and increasing the probability of collisions between circulating tumor cells and the aptamers on the micropillar surface. Secondly, by utilizing the high specificity of the aptamer for tumor cells, the accuracy and specificity of separation are improved.

Provided is a device for screening and separating circulating tumor cells (CTCs), comprising: a chamber module, the chamber module being provided with a mixing chamber, a screening chamber and a waste liquid chamber, and the mixing chamber, the screening chamber and the waste liquid chamber being sequentially communicated; a control module, the control module being mounted on the chamber module, and the control module being configured to control, according to the motion state thereof, whether to discharge a liquid from the mixing chamber to the screening chamber; a temperature control module, the temperature control module being mounted on the chamber module, and the temperature control module being configured to control the temperature in the mixing chamber; and a magnetic enrichment module, the magnetic enrichment module being configured to form a magnetic field in the mixing chamber. Provided is the device for screening and separating CTCs on the basis of immunomagnetic bead separation technology. The device has a compact structure and a small size, is convenient to operate, and has the function of simulating the constant-temperature environment in human bodies to assist in reaction incubation, thereby ensuring the reliability and precision of detection.

Disclosed herein are nucleic acid constructs that can be used to build genetic circuits for producing antibodies comprising split toxins. Also disclosed herein are methods of producing platelets comprising the antibodies. The platelets produced by the methods disclosed herein can be used to target circulating tumor cells.

Disclosed are methods for detecting and treating cancers (such as carcinoma, leukemia, lung cancer, colon cancer, central nervous system (CNS) cancer, melanoma, ovarian cancer, renal cancer, oral cancer, prostate cancer and / or breast cancer). The method may include receiving a sample from a patient (such as a sample from a biopsy, a sample from an extracellular vesicle, or a sample from a circulating tumor cell). The method may include determining whether a LY6C protein or a phosphorylated ANXA2 protein is detected in the sample. The method may include treating a patient for cancer by targeting the LY6C protein when the LY6C protein is detected (e.g., using photoimmunotherapy (PIT) or near infrared photoimmunotherapy (NIR-PIT)). or treating a patient for cancer by targeting an ANXA2 protein (e.g, using inhibitors, decoys, etc.) when the phosphorylated ANXA2 protein is detected.

1. The name of the design product: circulating tumor cell sorter. 2. The use of the design product: related to the field of in vitro diagnosis, for cell sorting, especially for circulating tumor cell sorting. 3. The design points of the design product: in shape. 4. The picture or photo that best shows the design points: perspective view 1. 5. The top view and bottom view have been embodied in other views, and the top view and bottom view are omitted.

The invention relates to the field of circulating tumor cell separation, particularly discloses a circulating tumor cell separation device based on a magnetic field, and aims at solving the problems that an existing magnetic separation device is poor in use universality, the internal circulation is easily influenced, and the separation efficiency is relatively low. The magnetic separation device comprises a base frame, lantern rings, a frame cylinder, a separation piece, a liquid inlet pipe, a discharge pipe, a liquid discharge pipe, a communication cavity, a first limiting sliding groove, a first blocking block, a second limiting sliding groove, a second blocking block, a first electromagnet, a second electromagnet, a sliding opening, a sliding plate, a shifting plate and a magnetic separation assembly, and the two sides of the base frame are each slidably provided with a sleeve plate matched with the upper end face of the shifting plate in an abutting mode; a first control assembly for controlling the first plugging block is arranged on the sleeve plate on the left side, and a second control assembly for controlling the second plugging block is arranged on the sleeve plate on the right side. The device can change the diameter of a flow channel in the separation liquid inlet pipe, facilitates real-time and efficient separation, can flexibly adjust magnetic force, and is high in universality and more flexible to use.

The invention discloses a magnetic field-fluid field synergistic micro-fluidic chip and application thereof. The magnetic field-fluid field synergistic micro-fluidic chip comprises a top inlet and outlet layer 1, a middle micro-fluidic channel layer 2, a bottom substrate layer 3, a sample inlet 4, a buffer solution inlet 5, a sample outlet 6, a waste liquid outlet 7, a sample input flow channel 8, a buffer solution input flow channel 9, a waste liquid output flow channel, a main body flow channel 10, a waste liquid output flow channel 11, a sample output flow channel 12, an empty window 13 and a magnet 14. According to the micro-fluidic chip and the related detection system, circulating tumor cell suspension with extremely low content can be rapidly, simply and conveniently separated from a cancer patient blood sample with complex components, and the obtained cell suspension is high in purity and clean in background and can be used for subsequent downstream analysis.

The application relates to the technical field of biological medicine, in particular to a alginate / polyethyleneimine composite modified magnetic nano probe and a preparation method and application thereof. The application discloses an alginate / polyethyleneimine composite modified magnetic nano probe, which comprises a composite polymer modified magnetic material and an aptamer connected to the composite polymer modified magnetic material; the composite polymer comprises alginate and polyethyleneimine; the magnetic material in the composite polymer modified magnetic material is Fe3O4 magnetic nano particle; and the aptamer comprises an amino-modified CSV aptamer and / or an amino-modified EpCAM aptamer. The magnetic probe disclosed by the application can sort circulating tumor cells directly in 1 milliliter of patient whole blood without lysing red blood cells, and has high sorting efficiency.

The application discloses a lock-key type DNA assembly for circulating tumor cell marker protein multiplex analysis, and belongs to the technical field of biomedical molecular diagnosis. The lock-key type DNA assembly comprises a lock type DNA assembly and a key type DNA. The lock type DNA assembly comprises a 16nt double-stranded displacement region, a 10nt single-stranded branch point region, a 7nt single-stranded closed region and a covalent double-stranded signal region containing a plurality of fluorescent groups. The key type DNA is a single-stranded sequence modified on an antibody. The application realizes in-situ signal amplification and CTC marker protein multiplex analysis on a single cell level based on the lock-key type DNA assembly design, provides a theoretical basis for circulating tumor cell multiplex detection analysis of cancer, and provides a new method for further realizing precise diagnosis and individualized treatment of cancer.

Disclosed herein are compositions and methods of fixing and staining rare cells. Further, disclosed herein are methods of identifying circulating tumor cells (CTC). In some embodiments, the method includes: imaging a cell sample to identify a cell of interest; determining a first pixel intensity of a stained nuclear area; determining a second pixel intensity of a background area; calculating a ploidy status of the cell of interest by subtracting the second pixel intensity from the first pixel intensity; and determining whether the cell of interest is a CTC based on the ploidy status. The method may be computer implemented, such that the method uses a machine learning algorithm to identify a feature; process the feature to extract a parameter of interest; analyze the parameter of interest; and when the parameter of interest is greater than or less than a pre-determined threshold, classify the cell of interest as a CTC.