Microfluidic Chip and Flow Cytometry for Examination of the Antiplatelet Effect of Ticagrelor / 中国医学科学院学报

Objective To examine the antiplatelet effect of ticagrelor by microfluidic chip and flow cytometry under shear stress in vitro. Methods Microfluidic chip was used to examine the effect of ticagrelor on platelet aggregation at the shear rates of 300/s and 1500/s.We adopted the surface coverage of platelet aggregation to calculate the half inhibition rate of ticagrelor.The inhibitory effect of ticagrelor on ADP-induced platelet aggregation was verified by optical turbidimetry.Microfluidic chip was used to construct an in vitro vascular stenosis model,with which the platelet reactivity under high shear rate was determined.Furthermore,the effect of ticagrelor on the expression of fibrinogen receptor (PAC-1) and P-selectin (CD62P) on platelet membrane activated by high shear rate was analyzed by flow cytometry. Results At the shear rates of 300/s and 1500/s,ticagrelor inhibited platelet aggregation in a concentration-dependent manner,and the inhibition at 300/s was stronger than that at 1500/s (both P<0.001).Ticagrelor at a concentration ≥4 μmol/L almost completely inhibited platelet aggregation.The inhibition of ADP-induced platelet aggregation by ticagrelor was similar to the results under flow conditions and also in a concentration-dependent manner.Ticagrelor inhibited the expression of PAC-1 and CD62P. Conclusion We employed microfluidic chip to analyze platelet aggregation and flow cytometry to detect platelet activation,which can reveal the responses of different patients to ticagrelor.

Neurotoxicity mechanism of aconitine in HT22 cells studied by microfluidic chip-mass spectrometry / 药物分析学报

Aconitine,a common and main toxic component of Aconitum,is toxic to the central nervous system.However,the mechanism of aconitine neurotoxicity is not yet clear.In this work,we had the hypothesis that excitatory amino acids can trigger excitotoxicity as a pointcut to explore the mechanism of neurotoxicity induced by aconitine.HT22 cells were simulated by aconitine and the changes of target cell metabolites were real-time online investigated based on a microfluidic chip-mass spectrometry system.Meanwhile,to confirm the metabolic mechanism of aconitine toxicity on HT22 cells,the levels of lactate dehydrogenase,intracellular Ca2+,reactive oxygen species,glutathione and superoxide dismutase,and ratio of Bax/Bcl-2 protein were detected by molecular biotechnology.Integration of the detected results revealed that neurotoxicity induced by aconitine was associated with the process of excitotoxicity caused by glutamic acid and aspartic acid,which was followed by the accumulation of lactic acid and reduction of glucose.The surge of extracellular glutamic acid could further lead to a series of cascade reactions including intracellular Ca2+overload and oxidative stress,and eventually result in cell apoptosis.In general,we illustrated a new mechanism of aconitine neurotoxicity and presented a novel analysis strategy that real-time online monitoring of cell metabolites can provide a new approach to mechanism analysis.

Application progress of microfluidic chip in isolation and capture of circulating tumor cells / 中华检验医学杂志

The amount of circulating tumor cells(CTC) in peripheral blood is very small, which is difficult to isolate. Microfluidic chips are becoming a hot area in recent years because of their portability, high sensitivity, high capture,and low cost. Microfluidic devices have been shown to maintain optimal performance for CTC isolation capture, including flux, purity, recovery, and clinical relevance. However, microfluidic technology is still unable to recover CTC with high recovery and purity.

Recent progress on detection techniques for human hormones / 药学学报

Human hormones at trace levels play a vital role in the regulation of a variety of functions and systems in the body, and an imbalance in hormone levels can lead to the emergence and development of diverse diseases. Therefore, the development of reliable sample pretreatment methods and sensitive and accurate analytical techniques for human hormone detection could contribute to the prevention, diagnosis and treatment of diseases, providing significant improvement for human health. Human samples which are usually used to detecting hormones, such as blood, saliva, urine and other matrix are more complex, so sample pretreatment is an important step to ensure the accuracy and reliability in the detection of hormones. In this review three common sample pretreatment methods including solid phase extraction (SPE), liquid-liquid extraction (LLE) and protein precipitation (PP) methods are discussed. Then, recent research progress in conventional techniques like liquid/gas chromatography and liquid/gas chromatography-mass spectrometry (LC/GC-MS/MS), as well as some novel strategies, such as immunoassay including chemiluminescence immunoassay (CLIA), lateral-flow immunoassay (LFIA) and time-resolved fluoroimmunoassay (TRFIA), and sensor technology including electrochemical (EC), fluorescent (FL) and surface-enhanced Raman scattering (SERS) sensors, and microfluidic chip analysis are discussed for human hormone detection. Finally, the future perspective on the use of these methods for hormone detection is considered. It is hoped to provide powerful insights to researchers for the relevant researches.

Study on Platelet Adhesion and Aggregation Induced by Gradient Shear Stress Using Microfluidic Chip Technology / 中国实验血液学杂志

OBJECTIVE@#To study the effect of gradient shear stress on platelet aggregation by microfluidic chip Technology.@*METHODS@#Microfluidic chip was used to simulate 80% fixed stenotic microchannel, and the hydrodynamic behavior of the stenotic microchannel model was analyzed by the finite element analysis module of sollidwork software. Microfluidic chip was used to analyze the adhesion and aggregation behavior of platelets in patients with different diseases, and flow cytometry was used to detect expression of the platelet activation marker CD62p. Aspirin, Tirofiban and protocatechuic acid were used to treat the blood, and the adhesion and aggregation of platelets were observed by fluorescence microscope.@*RESULTS@#The gradient fluid shear rate produced by the stenosis model of microfluidic chip could induce platelet aggregation, and the degree of platelet adhesion and aggregation increased with the increase of shear rate within a certain range of shear rate. The effect of platelet aggregation in patients with arterial thrombotic diseases were significantly higher than normal group (P<0.05), and the effect of platelet aggregation in patients with myelodysplastic disease was lower than normal group (P<0.05).@*CONCLUSION@#The microfluidic chip analysis technology can accurately analyze and evaluate the platelet adhesion and aggregation effects of various thrombotic diseases unde the environment of the shear rate, and is helpful for auxiliary diagnosis of clinical thrombotic diseases.

Sensitive detection of microRNAs using polyadenine-mediated fluorescent spherical nucleic acids and a microfluidic electrokinetic signal amplification chip / 药物分析学报

The identification of tumor-related microRNAs(miRNAs)exhibits excellent promise for the early diag-nosis of cancer and other bioanalytical applications.Therefore,we developed a sensitive and efficient biosensor using polyadenine(polyA)-mediated fluorescent spherical nucleic acid(FSNA)for miRNA analysis based on strand displacement reactions on gold nanoparticle(AuNP)surfaces and electrokinetic signal amplification(ESA)on a microfluidic chip.In this FSNA,polyA-DNA biosensor was anchored on AuNP surfaces via intrinsic affinity between adenine and Au.The upright conformational polyA-DNA recognition block hybridized with 6-carboxyfluorescein-labeled reporter-DNA,resulting in fluores-cence quenching of FSNA probes induced by AuNP-based resonance energy transfer.Reporter DNA was replaced in the presence of target miRNA,leading to the recovery of reporter-DNA fluorescence.Sub-sequently,reporter-DNAs were accumulated and detected in the front of with Nafion membrane in the microchannel by ESA.Our method showed high selectivity and sensitivity with a limit of detection of 1.3 pM.This method could also be used to detect miRNA-21 in human serum and urine samples,with re-coveries of 104.0％-113.3％and 104.9％-108.0％,respectively.Furthermore,we constructed a chip with three parallel channels for the simultaneous detection of multiple tumor-related miRNAs(miRNA-21,miRNA-141,and miRNA-375),which increased the detection efficiency.Our universal method can be applied to other DNA/RNA analyses by altering recognition sequences.

Construction of a blood-brain barrier microfluidic chip model and evaluation of the permeability of active components in traditional Chinese medicine / 药学学报

A blood-brain barrier microfluidic chip platform for studying the permeability of active components in traditional Chinese medicine was developed. This model used primary human brain microvascular endothelial cells on a microfluidic chip consisting of two perpendicularly-crossing channels and a single layer porous polycarbonate membrane. The physiological shear stress in the human vasculature was also modeled in this device. Cell viability on the chip was monitored by cell staining and immunofluorescence staining. The cells spread well and the structure of an intercellular adhesion protein was satisfactory. The permeability of fluorescent tracers and three model drugs and the functional expression of P-glycoprotein (P-gp)on the blood-brain barrier were investigated. The results show that the apparent permeability coefficients (Papp) of the fluorescent tracers and three model drugs were consistent with those reported in the literature, and P-gp on the chip showed normal function, indicating that there was a complete structure and a functional BBB. The permeability of six active components of traditional Chinese medicine was investigated through this microfluidic chip and the drug concentration was determined by HPLC-MS/MS to obtain the Papp of each component. The Papp of corydaline was (4.51 ± 1.90)×10-7 cm·s-1, the Papp of tetrahydropalmatine was (9.10 ± 6.59)×10-7 cm·s-1, and the Papp of imperatorin was (9.38 ± 2.53)×10-7 cm·s-1; the concentration of isoimperatorin, baicalin and chlorogenic acid was below the limit of quantification, which suggested that isoimperatorin, baicalin and chlorogenic acid have poor permeability in this BBB chip. This blood-brain barrier microfluidic platform possesses a complete barrier function and near-physiological conditions and could be a valuable in vitro tool for drug permeability evaluation.

Isothermal amplification technology based on microfluidic chip / 生物工程学报

Polymerase chain reaction (PCR) is the gold standard for nucleic acid amplification in molecular diagnostics. The PCR includes multiple reaction stages (denaturation, annealing, and extension), and a complicated thermalcycler is required to repetitively provide different temperatures for different stages for 30-40 cycles within at least 1-2 hours. Due to the complicated devices and the long amplification time, it is difficult to adopt conventional PCR in point-of-care testing (POCT). Comparing to conventional PCR, isothermal amplification is able to provide a much faster and more convenient nucleic acid detection because of highly efficient amplification at a constant reaction temperature provided by a simple heating device. When isothermal amplification is combined with microfluidics, a more competent platform for POCT can be established. For example, various diagnosis devices based on isothermal amplification have been used to rapidly and conveniently detect SARS-CoV-2 viruses. This review summarized the recent development and applications of the microfluidics-based isothermal amplification. First, different typical isothermal amplification methods and related detection methods have been introduced. Subsequently, different types of microfluidic systems with isothermal amplification were discussed based on their characteristics, for example, functionality, system structure, flow control, and operation principles. Furthermore, detection of pathogens (e.g. SARS-CoV-2 viruses) based on isothermal amplification was introduced. Finally, the combination of isothermal amplification with other new technologies, e.g. CRISPR, has been introduced as well.

Preliminary application experience of disk microfluidic chip for detecting CALR gene mutation in patients with cerebral infarction / 中华检验医学杂志

Objective:To establish a disk (CD) microfluidic chip detection platform for the rapid detection of CALR-1 and CALR-2 mutations in patients with cerebral infarction, and summarize its clinical application value.Methods:Based on microfluidic technology and loop mediated isothermal amplification technology, a CD microfluidic chip detection platform for simultaneous detection of CALR-1 and CALR-2 gene mutations were established, and the sensitivity, specificity, repeatability and accuracy of the platform were verified. A total of 124 patients with cerebral infarction treated in Huashan Hospital, Shanghai Medical College, Fudan University from November 2019 to March 2021 were prospectively selected into the experimental group; and 80 healthy subjects were included in the control group. The CALR-1 and CALR-2 gene mutations in anticoagulant peripheral blood samples were detected by the CD microfluidic chip. Each chip could detect 4 samples at the same time and synchronously detect 3 indexes of each sample. The detection results could be obtained after isothermal amplification for 40 min. At the same time, sequencing method was used to verify the test results, and the consistency of the results of the two detection methods was compared.Results:Using this CD microfluidic chip platform, the synchronous amplification of 3 indexes in the sample could be completed within 40 min without the need of thermal circulation, and the whole detection process of the sample could be completed within 60 min. For samples with a high concentration of target nucleic acid, typical positive signals could be visualized after amplification for 10 min, and the test results would be available within 30 minutes after receiving the samples. The detection sensitivity of CD microfluidic chip method for CALR-1 and CALR-2 mutation load concentration was 1.0% and 0.5% respectively. Nonspecific amplification was not observed for the non-target nucleic acid samples, indicating the high specificity of this method. The coincidence rates of intra and inter batch repeatability were 100% (20/20) respectively. Two samples with CALR gene mutation were found in the cerebral infarction group, both of which were CALR-1 mutations (L367fs*46). There was no CALR-1 or CALR-2 mutation in the control group. The detection results of CD microfluidic chip method were completely consistent with the sequencing verification results (100% [204/204]).Conclusions:The CD microfluidic chip method could be used for the detection of CALR-1 and CALR-2 gene mutations in clinical samples of patients with cerebral infarction. This method has the advantages of high detection sensitivity, good detection specificity, fast detection speed and high detection flux, which is helpful to clarify the etiology of patients with cerebral infarction.

Extraction of exosome by gel electrophoresis microfluidic chip and determination of miRNA-21 in exosome of human plasma / 生物工程学报

We developed a high-efficiency microfluidic chip for extracting exosomes from human plasma. We collected peripheral blood from normal human, designed and fabricated a microfluidic chip based on nanoporous membrane and agarose gel electrophoresis to isolate exosomes. The extracted exosomes were characterized by transmission electron microscopy, nanosight and Western blotting, the morphology, concentration and particle size of exosomes were identified and analyzed. Meanwhile, we used ultracentrifugation and microfluidic chip to isolate exosomes separately. The particle size and concentration of the exosomes extracted by two methods were compared and analyzed, and their respective extraction efficiency was discussed. Finally, the expression level of miRNA-21 in exosomes was analyzed by RT-PCR. The microfluidic chip isolated (in 1 hour) high-purity exosomes with size ranging from 30-200 nm directly from human plasma, allowing downstream exosomal miRNA analysis. By comparing with ultracentrifugation, the isolation yield of microfluidic chip was 3.80 times higher than ultracentrifugation when the volume of plasma sample less than 100 μL. The optimized parameters for exosome isolation by gel electrophoresis microfluidic chip were: voltage: 100 V; concentration of agarose gel: 1.0%; flow rate of injection pump: 0.1 mL/h. The gel electrophoresis microfluidic chips could rapidly and efficiently isolate the exosomes, showing great potential in the research of exosomes and cancer biomarkers.

Advances of using microfluidic chips for research and diagnosis of pulmonary inflammatory diseases / 生物工程学报

Microfluidic chip technology integrates the sample preparation, reaction, separation and detection on a chip. It consists a network of microchannels, which controls the whole system through fluid. With the advantages of portability, high throughput, and the ability to simulate the microenvironment in vivo, it has a broad application prospect in the research of disease diagnosis, pathogenesis and drug screening. Pulmonary inflammatory disease is a common disease usually caused by bacterial, viral and fungal infections. Early pneumonia is often difficult to diagnose due to lack of obvious respiratory symptoms or the symptoms are mostly atypical, but the disease progresses rapidly. Recently, microfluidic chip technology has been increasingly used to the study of pulmonary inflammatory diseases. In particular, it has been used to develop a "lung-on-a-chip" model, which can reproduce the key structure, function and mechanical properties of human alveolar capillary interface (i.e., the basic functional unit of a living lung), and well simulate the alveoli in vitro. Compared with the cell and animal models, this multifunctional micro experimental platform has great advantages. This article summarizes the advances of using microfluidic chips for the research and diagnosis of pulmonary inflammatory diseases, with the aim to provide new ideas for researchers in this area.

Experimental Study on Separation of Fetal Nucleated Red Blood Cell from the Whole Blood Using Microfluidic Chip / 医用生物力学

Objective To seperate fetal nucleated red blood cells (fNRBCs) from the whole maternal peripheral blood effectively by designing a circular channel microfluidic chip. Methods A microfluidic chip is designed by utilizing the margination in blood flow and the specific adhesion characteristics of immuno-agent anti-CD147. With the whole umbilical cord blood, the effects of different shear forces on the enrichment of fNRBCs was studied by immunofluorescence counting. Results Increasing shear rate in microfluidic chip could improve the number of captured fNRBCs compared with the static adhesion. With the increase of shear rate of blood flow, the number of the captured cells increased at first, and then decreased. Conclusions The use of microfluid chip can effectively seperate fNRBCs from the whole blood. The results provide an experimental reference for the non-invasive prenatal diagnosis research and the exploration on the mechanism of fetal cell migration.

High throughput detection and characterization of red blood cells deformability by combining optical tweezers with microfluidic technique / 生物医学工程学杂志

A high throughput measurement method of human red blood cells (RBCs) deformability combined with optical tweezers technology and the microfluidic chip was proposed to accurately characterize the deformability of RBCs statistically. Firstly, the effective stretching deformation of RBCs was realized by the interaction of photo-trapping force and fluid viscous resistance. Secondly, the characteristic parameters before and after the deformation of the single cell were extracted through the image processing method to obtain the deformation index of area and circumference. Finally, statistical analysis was performed, and the average deformation index parameters (

Construction of a concentration gradient microfluidic chip platform for the rapid screening of drugs active against Candida albicans / 药学学报

Drug screening against Candida albicans has become more urgent due to the increasing incidence of infection and the development of drug-resistant strains. The microfluidic chip technique has shown great potential for high-throughput drug screening. In this study we developed a concentration gradient microfluidic chip platform for drug screening against Candida albicans. The generated concentration gradient on this platform was investigated qualitatively by monitoring the distribution of the fluorescent tracer fluorescein sodium and quantitatively by following the distribution of the model drug fluconazole as analyzed by HPLC; the effect of different flow conditions on the concentration gradient were determined. The ratio of the two aqueous phase flow rates was determined in the subsequent drug screening studies. Alamar Blue, an indicator of cell viability, was used in the susceptibility test for amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, terbinafine, 5-fluorocytosine and caspofungin as carried out on the established chip platform. The MIC range of the drugs, which was consistent with the MIC values of the CLSI-recommended standard, were obtained quickly and efficiently through the use of this platform, indicating that this new platform can quickly screen a series of antibacterial drugs in one run. In addition, the strain of Candida albicans we used showed resistance to terbinafine in our platform assay, consistent with the results of a 96-well plate assay, indicating that the platform can also be used for rapid screening of resistant strains.

Construction of microfluidics-based fallopian tube model for mimicking fertilization and early embryo culture in vivo / 中国组织工程研究

BACKGROUND: With the increasing proportion of infertility in the population, more and more attentions have been paid on assisted reproductive techniques. Fertilization and early embryo culture are the significant parts of assisted reproductive techniques; however, they remain unchanged in the last few decades. OBJECTIVE: To design a novel microfluidics-based fallopian tube model that can mimic the microenvironment of fertilization and early embryo culture in vivo. METHODS: Microfluidic device was manufactured by soft lithography method to mimic the anatomical characteristic of fallopian tube in vivo. Mouse oviduct primary epithelial cells were cultured and purified by explants culture method, and then the purified cells were identified by keratin immunofluorescence method. Epithelial cells were then loaded into the channel to mimic the biochemical environment of fallopian tube in vivo. The chip was connected to the automatic liquid changing device to mimic the liquid environment of fallopian tube in vivo. RESLUTS AND CONCLUSION: (1) The channel of this model is cylindrical with 2 cm of height and 1 cm of diameter, which were in accordance with the anatomical characteristic of the isthmus of fallopian tube in shape. (2) The keratin immunofluorescence was positive, which indicated that mouse oviduct primary epithelial cells can be obtained by explants culture method. (3) The cells were loaded into the channel to cover the wall of channel, which provided a biochemical microenvironment similar to that in vivo for fertilization and early embryo culture. After the chip was connected to the automatic liquid changing device, metabolic waste could be taken away and nutrient substance can be replenished in time, which mimics the real fluid environment in vivo. (4) This study combined microfluidics technology and assisted reproductive techniques to design a novel fallopian tube model, which mimics the micro-environment of fertilization and early embryo culture in vivo. This study has laid a foundation for further improvement of assisted reproductive techniques and the rate of fertilization and embryo optimization.

Research status of dynamic three-dimensional tissue culture driving methods / 中国组织工程研究

BACKGROUND: In vitro models are widely used in toxicology, pathology, and pharmaceutical research due to their short experimental cycles, low cost, and small species differences compared with animal models. Dynamic three-dimensional tissue culture mode is an important trend in the development of in vitro models. Dynamic three-dimensional culture in vitro models can be achieved by means of driving fluids in microfluidic systems. OBJECTIVE: To describe the microfluidic driving methods in the field of microfluidics, their respective advantages and disadvantages, and the application of different driving methods to different tissue culture requirements. METHODS: A computed-based retrieval of CNKI and Web of Science databases was performed for the articles concerning dynamic three-dimensional tissue culture and microfluidic driving methods to achieve dynamic culture of cells or tissues. The search terms were “microfluidic; micropump; organ-on-chip; three-dimensional tissue culture” in English and Chinese, respectively. RESULTS AND CONCLUSION: The microfluidic driving methods include passive driving and active driving. Whereas passive driving includes surface tension pump, osmotic pump and gravity pump. Active driving includes syringe pump and peristaltic pump. Each driving method has its advantages and disadvantages. To achieve accurate control of the medium flow rate in a dynamic three-dimensional tissue culture system, the best choice is to use syringe pumps or valve-type peristaltic pumps. To achieve closed-loop flow of culture medium in a dynamic three-dimensional tissue culture system, the best choice is to use gravity pumps or peristaltic pumps. To fulfill the need for a sterile environment in the experimental process in a dynamic three-dimensional tissue culture system, the best choices are surface tension pumps, gravity pumps, and pneumatic peristaltic pumps. To achieve high-throughput culture in dynamic three-dimensional tissue culture systems, the best choices are surface tension pumps, gravity pumps and pneumatic peristaltic pumps.

Rapid generation of double-layer emulsion droplets based on microfluidic chip / 生物工程学报

In vitro compartmentalization (IVC) links genotype and phenotype by compartmentalizing individual genes (including expression system) or cells into a micro-droplet reaction region. Combined with fluorescence-activated cell sorting (FACS), it can detect and separate single droplets in ultra-high throughput. IVC-FACS screening method has been widely used in protein engineering, enzyme directed evolution, etc. However, it is difficult to control the homogeneity of droplet size by mechanical dispersion method in previous studies, which seriously affects the quantitative detection of droplets and reduces the efficiency and accuracy of this screening method. With the rapid development of microfluidic chip manufacturing technology, the microfluidic chip-based methods for droplet generation are becoming more efficient and controllable. In this study, firstly, the water-in-oil (W/O) single-layer droplet generation chip was used to prepare single-layer monodisperse W1/O droplets at a high generation frequency, and then the W1/O droplets were reinjected into water-in-oil-in-water (W/O/W) double-layer droplet generation chip to prepare uniform W1/O/W2 double-layer emulsion droplets. By optimizing the flow rate and ratio of the oil and water phases, a single-layer micro-droplet can be generated with a diameter range from 15.4 to 23.2 μm and remain stable for several days under normal incubation. Then the single-layer droplets were reinjected into the double emulsion generation chip. By adjusting the flow rate of drop phase, oil phase and water phase, the double-layer emulsion droplets with a diameter range from 30 to 100 μm at a rate of 1 000 droplets/s could be obtained. Escherichia coli embedded in the double-layer emulsion droplets could be cultured and induced for protein expression. This study lays a foundation for the establishment of a high-throughput screening method based on the droplet and flow cytometry.

Application and prospect of microfluidic chip in central nervous system diseases / 生物工程学报

In recent years, many human central nervous systems (CNS) of microfluidic platforms and related disease models in vitro have been built with the continuous development of the microfluidic technology and biological microelectronics mechanical systems technology. Microplatforms have emerged to provide a better approximation of the in vivo scenario with better control of the structure, microenvironment and stimuli. This review summarized the basic technology of microfluidic chips in CNS and the application in CNS diseases. In addition, the research of microfluidic chip in CNS diseases has been also prospected. We also highlight challenges that can be addressed with interdisciplinary efforts to achieve more biomimicry.

Research advancement in the construction and applications of microfluidic devices for in vitro blood-brain barrier research / 药学学报

The blood-brain barrier (BBB) not only maintains the stability of the environment within the central nervous system by controlling the transport of substances on both sides of the blood and brain, but also plays an important role in the R&D of new drugs for neurological disorders. The establishment of an in vitro high-fidelity model to study BBB function is imperative for assessing barrier permeability of drugs and xenobiotics. However, the complexity of the BBB structure makes it difficult to replicate with an in vitro model. Compared to the traditional in vitro BBB model, the BBB-on-chip provides certain advantages in miniaturizing the system, reducing the amount of cells and medium required, and allowing simultaneously induction of shear stress. We review here the BBB-on-chip models from their establishment and characterization to applications in research of neuroinflammation, brain tumor and drug evaluation.

Analysis of Pharmacological Effect of Total Tannins from Spatholobi Caulis on Cervical Cancer HeLa Cells by 3D Microfluidic Chip / 中国实验方剂学杂志

Objective:To study on the chemical constituents of total tannins from Spatholobi Caulis,and to analyze the pharmacodynamics and mechanism of total tannins from Spatholobi Caulis on cervical cancer HeLa cells. Method:UPLC-Q-TOF/MS was used to qualitatively analyze the composition of total tannins from Spatholobi Caulis.The appropriate concentration and time of administration were screened by 3 dimensional(3D) microfluidic chip.Flow cytometry was used to determine the effect of total tannins from Spatholobi Caulis on the cell cycle and apoptosis of cervical cancer HeLa cells and analyzed by FlowJo v10.0.7 and ModFit LT 3.2 software.Enzyme-linked immunosorbent assay(ELISA) was used to determine the changes of vascular endothelial growth factor(VEGF)-A and Caspase-3 factors in cervical cancer HeLa cells supernatant treated with total tannins from Spatholobi Caulis. Result:Total of 15 components in total tannins from Spatholobi Caulis were identified or inferred.The low,medium and high dosages of total tannins from Spatholobi Caulis were 0.5,1.0, 2.0 g·L-1 and the best time of administration was 36 h.The proportions of early and late apoptosis of cervical cancer HeLa cells increased significantly in the apoptosis analysis after being treated by total tannins from Spatholobi Caulis.The DNA synthesis early phase(G0/G1 phase) of cervical cancer HeLa cells significantly increased,and the DNA synthesis phase(S phase) and the DNA synthesis late phase(G2/M phase) reduced.After being treated with total tannins from Spatholobi Caulis,the expression of VEGF-A in cervical cancer HeLa cells supernatant was significantly decreased and the expression of Caspase-3 was significantly increased. Conclusion:Spatholobi Caulis is rich in tannins,which can significantly inhibit the proliferation of cervical cancer HeLa cells and promote its apoptosis.This paper can provide the basis for further research of total tannins from Spatholobi Caulis.