ABSTRACT
The intestine is the main site of oral drug absorption, and the epithelial cells of the intestine contain villi and microvilli, which promote secretion, cell adhesion, and absorption by increasing surface area and other factors. Traditional two-dimensional/three-dimensional (2D/3D) cell culture models and animal models have played an important role in studying drug absorption, but their application is limited due to the lack of sufficient predictability of human pharmacokinetics or ethical issues, etc. Therefore, mimicking the core structure and key functions of the human intestine based on in vitro live cells has been the focus of research on constructing a microfluidic chip-based intestinal model. The model is a microfluidic chip bionic system that simulates the complex microstructure, microenvironment, and physiological functions of the human intestine using microfabrication technology. Compared with 2D cell culture and animal experiments, the intestinal microarray model can effectively simulate the human in vivo environment and is more specific in drug screening. The research progress and applications in disease modeling, drug absorption and transport of intestinal microarray models and intestine-related multi-organ coupled microarray models at home and abroad were reviewed in this paper. The current challenges of intestinal chip simulating intestinal homeostasis and diseases were summarized，in order to provide reference for the further establishment of a more reliable in vitro intestinal chip model.
ABSTRACT
Digital polymerase chain reaction(dPCR)is a PCR technology that realizes accurate quantification of single-copy nucleic acid molecules by dividing the reaction system into tens of thousands of independent PCR reaction units for single-molecule-level amplification and integrating Poisson distribution.Due to its single-copy sensitivity and accurate quantification without the need of standard curves,dPCR has been widely used in disease diagnosis.By introducing technologies such as stepped emulsification and three-dimensional imaging,dPCR has been greatly improved in terms of accuracy,multiplexability and turnaround time,significantly enhancing its performance in clinical disease diagnosis.Based on this,this paper traced the technological development history of dPCR,gave an overview of its application in detection of tumors,infections and other diseases,and further discussed the challenges and opportunities of the development of dPCR,with the aim of providing a reference for the development and utilization of dPCR in the future,and promoting the high-quality development of molecular technology in clinical testing.
ABSTRACT
BACKGROUND:The imbalance of matrix synthesis and degradation is the main cause of nucleus pulposus degeneration.Small molecule drug Kartogenin(KGN)can restore the balance of matrix synthesis and degradation.Sustained release of KGN using an appropriate drug delivery system is essential for the long-term and effective treatment of KGN.OBJECTIVE:To prepare the injectable hydrogel microspheres by encapsulating KGN with gelatin methacryloyl(GelMA)by microfluidic technology and to investigate the biocompatibility and biological function of nucleus pulposus cells.METHODS:β-Cyclodextrins(β-CD)and KGN were mixed firstly and then mixed with 10%GelMA at a volume of 1:9.Injectable hydrogel microspheres GelMA@β-CD@KGN were prepared by microfluidic technology.The micromorphology of the microspheres was characterized using a scanning electron microscope.The drug release of hydrogel microspheres immersed in PBS within one month was measured.Nucleus pulposus cells were isolated from SD rats and passage 1 cells were cultured in three groups.In the control group,nucleus pulposus cells were cultured separately.In the other two groups,GelMA@β-CD microspheres and GelMA@β-CD@KGN microspheres were co-cultured with nucleus pulposus cells.Cell proliferation was detected by CCK-8 assay and cell survival was detected by live/dead cell staining.Cells were cultured by two complete media with and without interleukin-1β with two kinds of microspheres.mRNA expressions of matrix synthesis and decomposing proteins in nucleus pulposus cells were detected by RT-PCR.RESULTS AND CONCLUSION:(1)Under the scanning electron microscope,the GelMA@β-CD@KGN microspheres after lyophilization were regularly spherical,highly dispersed,uniform in size and full in shape.GelMA@β-CD@KGN microspheres sustained drug release in vitro,reaching 62%of the total drug release at 30 days.(2)Live/dead cell staining showed that GelMA@β-CD@KGN could maintain the activity of nucleus pulposus cells.CCK-8 assay showed that GelMA@β-CD@KGN could promote the proliferation of nucleus pulposus cells.(3)In the complete media with and without interleukin-1β,mRNA expression of aggrecan and type Ⅱ collagen was higher in the GelMA@β-CD@KGN microsphere group than that in the GelMA@β-CD microsphere group(P<0.05,P<0.01);mRNA expression of matrix metalloproteinase 13 and platelet reactive protein disintegrin metallopeptidase 5 was lower than that in the GelMA@β-CD microsphere group(P<0.01).(4)These findings indicate that GelMA@β-CD@KGN microspheres have good biocompatibility and sustained drug release ability.As a drug delivery system,it is a kind of biomaterial with broad application prospects.
ABSTRACT
Objective To analyze the detection efficiency of p16INK4a protein combined with human papillomavirus and liquid-based cytology(LCT)in the screening of cervical precancerous lesions,and to provide a basis for cervical cancer preven-tion and treatment.Methods The results of p16INK4a staining of cervical epithelial cells,human papillomavirus testing and cer-vical cytology were analyzed in 139 inpatients at Guangzhou Women's and Children's Medical Center between January 2019 and December 2020.Of them,there were 111 patients with cervical intraepithelial neoplasia(CIN)and 28 cases of cervical inflam-matory disease.The efficacy of the three methods alone and in combination to screen for CIN lesions was compared.Results In the detection of CIN patients,the sensitivity of p16INK4a,microfluidic microarray and cervical cytology for detecting CIN and a-bove lesions was 91.89% ,94.59% and82.88% ,with specificity of 57.14% ,17.86% and46.43% ,and AUC of 0.75,0.56 and 0.65,respectively;while the sensitivity of"p16INK4a+LCT","p16INK4a+hrHPV","LCT+hrHPV"and their sen-sitivity were 96.40% ,97.30% ,94.59% and 99.10% ,their specificity was 85.71% ,92.86% ,89.29% and 92.86% ,and the AUC was 0.91,0.95,0.92 and 0.96,respectively.Conclusion The combined p16INK4a and hrHPV test helps to improve diagnostic accuracy and early detection,thus allowing for earlier intervention or treatment.This combined application allows for more accurate identification of low-grade and high-grade cervical intraepithelial neoplasia,providing more information for indi-vidualized patient management.
ABSTRACT
Microfluidic chip or lab-on-a-chip is a multidisciplinary cross-technology. Among them, organ-on-a-chip technology enables precise regulation of cells and microenvironment at micron level.This tecnology is expected to simulate in vivo human physiology and overcome the shortcomings of traditional animal models and cell culture techniques.In ophthalmology, organ-on-a-chip models are primarily focused on creating biomimetic models of the cornea, retina and posterior chamber to study diseases such as dry eye, glaucoma, age-related macular degeneration and diabetic retinopathy.In addition, continuous monitoring and real-time diagnosis of tear and intraocular fluid biomarkers using microfluidic chips have become a current research hot topic.The microfluidic chips also have a wide range of applications in drug analysis, drug development, and drug screening.This article reviews the recent progress and shortcomings of microfluidic chip in in vitro model construction, point-of-care testing and drug development, and discusses its future development in ophthalmology.
ABSTRACT
The immune response against infection is a multifaceted process encompassing the activation and migration of diverse immune cells, as well as the clearance of pathogens. The behaviors of immune cells and the identification of pathogens play pivotal roles as indicators for disease diagnosis and prediction. In recent years, the utilization of microfluidic chip technology has gained substantial attention within the areas of biology, pharmacology, and clinical research and diagnosis. This is primarily attributed to the numerous advantages it offers, including miniaturization, enhanced throughput, heightened sensitivity, expedited analysis, and reduced sample consumption. As a result, microfluidic technology has facilitated the development and utilization of immune cell behavioral assays, bacterial growth studies, and drug-screening assays. This paper is to review the application of microfluidic technology in the field of anti-infection immunity research, focusing on the analysis of migratory behavior of innate immune cells, deformation of their nuclei, and rapid identification of pathogenic bacteria and viruses. The primary objective of this review is to advance the application of microfluidic technology in research on both anti-infection immunity and clinical diagnosis.
ABSTRACT
Objective:To investigate the relationship between intracellular calcium level and neutrophil migration dysfunction in patients with sepsis.Methods:This study retrospectively collected 21 blood samples of patients with sepsis in the First Hospital of Jilin University from December 2017 to September 2018, and 20 healthy people were included as the control group. Peripheral blood neutrophils were isolated from the healthy controls and patients with sepsis using magnetic-activated cell sorting. Multichannel microfluidic microarray technology was used to detect the chemotactic migration of neutrophils. The levels of calcium in neutrophils from healthy controls and sepsis patients as well as in neutrophils from healthy controls that were pretreated with calcium chelators BAPTA-AM and EDTA were detected by flow cytometry using the calcium indicator Fluo-4.Results:The intracellular calcium levels were lower in neutrophils from sepsis patients than in those from healthy controls ( P<0.01). BAPTA-AM and EDTA could reduce the calcium level in neutrophils of healthy controls ( P<0.01). Microfluidics revealed that the migration speed, distance and gap-passing rate of neutrophils in microfluidics were significantly reduced after the decrease of intracellular calcium ( P<0.01). Conclusions:Reduced calcium levels in neutrophils of patients with sepsis may be closely related to the decreased cell migration. This study suggests that the migration impairment of neutrophils can be improved by regulating intracellular calcium levels, which provides a new idea for further research.
ABSTRACT
In recent years, advancements in microfabrication technology and tissue engineering have propelled the development of a novel platform known as organoid-on-a-chip for drug screening and disease modeling. This platform integrates organoids and organ-on-a-chip technologies, emerging as a promising approach for in vitro modeling of human organs. Organ-on-a-chip leverages microfluidic device to simulate the physiological environment of specific organs, offering a more dynamic and flexible setting that can mimic a more comprehensive human biological context. However, the lack of functional vasculature has remained a major challenge in this technology. Vascularization is crucial for the long-term cultivation and in vitro modeling of organoids, which is of great significance in drug development and personalized medical approaches. The authors reviewed the research progress in the construction of vascularized organoid-on-a-chip including the methods for constructing in vitro vascularized models, vascularization of organoids, etc, which may serve as a reference for the construction of fully functional vascularized organoid-on-a-chip.
ABSTRACT
Ion concentration polarization (ICP) is an electrical transport phenomenon that occurs at the micro-nano interface under the action of an applied electric field, and the ICP phenomenon can be used to enrich charged particles with high efficiency. The microfluidic chip has the advantages of high precision, high efficiency, easy integration and miniaturization in biochemical analysis, which provides a new solution and technical way for biochemical analysis. In response to the demand for the detection of trace charged target analytes in sample solution, the advantages of high enrichment multiplicity, convenient operation and easy integration of ICP are utilized to provide an effective way for microfluidic biochemical detection. The combination of ICP phenomenon and microfluidic analysis technology has been widely used in the fields of pre-enrichment of charged particles, separation of targets, and detection of target analytes in biochemical analysis. In this paper, the principle of ICP and the microfluidic ICP chip are briefly introduced. Under the action of external electric field, the co-ions pass through the ion-selective nanochannel, the counterions are rejected at the boundary of nanochannel to form a depletion zone, and the charged samples will be enriched at the boundary of the depletion zone. Then the preparation techniques and methods of ICP chips are summarized. Among them, the design of microfluidic channel structure and the preparation and design of nanostructures are emphasized. The basic single-channel structure is analyzed, and the parallel-channel structure as well as the integrated multi-functional microfluidic ICP chip are sorted out and summarized. The preparation methods of nanostructures in ICP chips and their respective advantages and disadvantages are listed, and it is summarized that the current mainstream means are the embedding method and the self-assembly method, and attention is paid to the design of nanostructures preparation methods by both of them. In addition, this paper also discusses how to optimize the enrichment efficiency of ICP chip, through the introduction of multi-field coupling, valve control and other means to achieve the optimization of the enrichment efficiency of target substances. Meanwhile, this paper provides a classified overview of the progress of application of ICP chips in biochemical analysis and detection. ICP chips have been widely used in the research and development of biosensors, which can be used for the enrichment and separation of a variety of analytes including small molecules, nucleic acids, proteins, and cells, etc. By changing the design of microfluidic structures, integrating detection methods and modifying specific antibodies, ICP chips have shown great potential in the fields of rapid enrichment and pre-processing of targets, separation of targets and highly sensitive detection. Finally, it is pointed out that ICP chips are facing challenges in improving enrichment efficiency and selectivity, and solving the problems of fluid control, mixing and transport to match the biological properties of target assay, and that microfluidic ICP chips have been continuously promoting the development of ICP chips through the improvement of materials, chip design and integration of multifunctional units, opening up new possibilities in the field of biochemical analysis methods and applications. It can be seen that microfluidic ICP chips have the advantages of low sample flow rate, good separation and enrichment, high detection efficiency, and easy integration and miniaturization, which have shown good research significance and practical prospects in the field of biochemical detection.
ABSTRACT
ObjectiveAt present, the matching reagents of commercially available rapid DNA instruments based on microfluidics chip technology are autosome short tandem repeat (STR) individual identification reagents. The non-recombining part of the human Y chromosome is widely used in forensic DNA analysis, particularly in cases where standard autosomal DNA profile is uninformative. Y-STR loci are useful markers to identify males and male lineages in forensic practice. In order to achieve rapid and fully integrated detection ofY-STR loci, this study constructed the RTyper Y27 microfluidic chip rapid detection system and validated the performance of this system. MethodsThe system was verified and evaluated by sensitivity, success rate, typing accuracy, peak height balance, sizing precision and accuracy, mock case sample tests, mixture detection ability, and inhibition tolerance. ResultsComplete Y-STR profiles can be obtained when the template amount of DNA standard 9948 was ≥8 ng, the number of blood cards was ≥3 pieces, and the number of oral swab scrapings was≥7 times. The success rate of fully integrated detection was 91.52%, and the concordance rates was 99.74% for 165 testing samples. The success rate of 115 blood spots in these samples was 90.43%, with a typing accuracy of 99.65%, the success rate of 50 buccal swabs was 94%, with a typing accuracy of 99.92%. There was no significant difference in typing accuracy between blood spots and buccal swab samples. The peak height ratio between different fluorescence channels was 89.81%. The standard deviation of allelic ladder for 10 runs was within 0.5 bp. The size differences between allele and corresponding allele in allelic ladder was within 0.5 bp. The maximum precision CV values within and between batches were 0.48% and 0.68%, respectively, which were lower than 15%. These data indicate that the system has good accuracy and precision. The system was capable of accurately typing oral swabs, blood cards, saliva cards, cigarette butts, blood swabs and seminal stains. Complete Y-STR profiles can be obtained and distinguish at the 1∶3 ratio of minor and major contributors in artificial male DNA mixtures. Complete Y-STR genotyping can be obtained under the interference of inhibitors, such as different concentrations of humic acid (50-400 mg/L), indigotin (20-100 nmol/L) and hemoglobin (100-500 μmol/L). ConclusionIn this study, the RTyper Y27 microfluidic chip rapid amplification system is combined with the Quick TargSeq 1.0 integrated system, and the Y-STR profile can be obtained in approximately 2 h. Through a series of verification experiments, the results show that the system has good repeatability, accuracy and stability, can meet the on-site Y-STR detection requirements, and can be used in forensic practice.
ABSTRACT
Microfluidic liver and kidney chips have become preferred model carriers in recent years for new drug development， pharmacological and toxicological research， mechanism exploration， and disease model construction. In the context of the USA. Food and Drug Administration allowing the use of in vitro model data as a substitute for animal model data in new drug applications when animal disease models are difficult to construct， microfluidic chips have received widespread attention due to their high throughput， ability to highly mimic biological characteristics of living organisms， convenient evaluation of drug toxicity in normal or pathological states with repeated dosing， real-time induction and monitoring of culture processes， and real-time data acquisition and analysis. In toxicology research， liver and kidney chips can construct in vitro models suitable for the pharmacological and toxicological detection of different substances by combining 2D monocultures and co-cultures from different species sources， 3D cultures， spheroids/organoid cells， precision-cut liver and kidney slices， immortalized cell lines， or sandwich-cultured cell lines. This model maximally simulates or retains the organ function and in vivo microenvironment of the liver and kidney， including specific physiological tissue structures， multicellular interactions/crosstalk， and multi-organ coordination/feedback， to obtain results similar to or the same as in vivo experimental data， reducing interspecies differences. At the same time， it greatly reduces the use of experimental animals and lowers costs. Microfluidic technology provides necessary shear force microenvironments for the cultivation of contents and solves problems encountered in the cultivation process of liver and kidney chips， such as insufficient tissue oxygen supply， nutrient deficiencies， and accumulation of metabolites， leading to cell apoptosis and even tissue necrosis fibrosis， which make it difficult to maintain long-term structure and function. This article reviewed the application of microfluidic technology combined with liver and kidney chips in Chinese medicine toxicology research. By summarizing the development of microfluidic technology， liver chips， kidney chips， and providing application examples of microfluidic liver and kidney chips in Chinese medicine toxicology research， combined with the characteristics of Chinese medicine administration， the article explored the advantages and future development directions of their application in the field of Chinese medicine toxicology research.
ABSTRACT
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.
ABSTRACT
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.
Subject(s)
Humans , Ticagrelor/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Flow Cytometry/methods , Microfluidics , Platelet AggregationABSTRACT
The kidney is the body's most important organ and the protein components in urine could be detected for diagnosing certain diseases. The amount of IgG protein in urine could be used to determine the degree of kidney function damage. IgG protein in human urine was detected by vertical flow paper-based microfluidic chip, double-antibody sandwich immunoreaction, and cell phone image processing. The results showed that using an IgG antibody concentration of 500 μg/mL and a gold standard antibody concentration of 100 μg/mL, the image signal showed a good linear relationship in the range of IgG concentration of 0.2-3.2 μg/mL, with R2=0.973 3 achieved. A complete set of detection devices were designed and the detection method showed good non-specificity.
Subject(s)
Humans , Microfluidics , Immunoglobulin G , Kidney , Microfluidic Analytical TechniquesABSTRACT
Objective To observe the inhibitory effect of Tirofiban on different shear-induced platelet aggregation, and to provide medication suggestions for the treatment of thrombosis in different hemodynamic environment. Methods Polydimethylsiloxane ( PDMS)-glass microchannel chips were fabricated by soft lithography. The whole blood of healthy volunteers anticoagulated with sodium citrate was collected and incubated with different concentrations of Tirofiban in vitro. The blood flowed through the straight microchannel or channel with 80% narrow for 150 seconds at the speed of 11 μL/ min and 52 μL/ min, respectively. The wall shear stress rates in straight channel at 11 μL/ min and 52 μL/ min were 300 s-1 and 1 500 s-1, respectively. The maximum wall shear rates in the channel with 80% occlusion at 11 μL/ min and 52 μL/ min were 1 600 s-1 and 7 500 s-1, respectively. The adhesion and aggregation images of fluorescent labeled platelets on glass surface were photographed with the microscope, and the fluorescent images were analyzed with Image J. The platelet surface coverage ratio was used as a quantitative index of platelet aggregation behavior, and the IC50 of Tirofiban for platelet inhibition was calculated under different shear rates. Flow cytometry was used to detect the platelet activation index (CD62P, PAC-1) in the whole blood at 52 μL/ min in channel with 80% occlusion. Results Tirofiban inhibited platelet aggregation in a dose-dependent manner, and the inhibitory effect was related to the shear rate. Under the shear rates of 11 μL/ min and 52 μL/ min, the aggregation was almost completely inhibited when the concentration in straight channel reached 100 nmol / L. When the concentration in channels with 80% occlusion reached 1 μmol / L, the aggregation was almost completely inhibited. IC50 values at 11 μL/ min and 52 μL/ min in straight channel were 2. 3 nmol / L and 0. 5 nmol / L, respectively. IC50 values at 11 μL/ min and 52 μL/ min in channels with 80% occlusion were 20. 73 nmol / L and 4. 5 nmol / L. Pathologically high shearforce induced an increase in platelet activation, which could be inhibited by Tirofiban. Conclusions Tirofiban can effectively inhibit shear-induced platelet aggregation, and different concentrations of Tirofiban should be given according to the thrombus formed in different shear force environment in clinic practice
ABSTRACT
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.
ABSTRACT
The direct coupling of solid-phase microextraction(SPME)to mass spectrometry(MS)(SPME-MS)has proven to be an effective method for the fast screening and quantitative analysis of compounds in complex matrices such as blood and plasma.In recent years,our lab has developed three novel SPME-MS techniques:SPME-microfluidic open interface-MS(SPME-MOI-MS),coated blade spray-MS(CBS-MS),and SPME-probe electrospray ionization-MS(SPME-PESI-MS).The fast and high-throughput nature of these SPME-MS technologies makes them attractive options for point-of-care analysis and anti-doping testing.However,all these three techniques utilize different SPME geometries and were tested with different MS instruments.Lack of comparative data makes it difficult to determine which of these methodologies is the best option for any given application.This work fills this gap by making a comprehensive comparison of these three technologies with different SPME devices including SPME fibers,CBS blades,and SPME-PESI probes and SPME-liquid chromatography-MS(SPME-LC-MS)for the analysis of drugs of abuse using the same MS instrument.Furthermore,for the first time,we developed different desorption chambers for MOI-MS for coupling with SPME fibers,CBS blades,and SPME-PESI probes,thus illustrating the universality of this approach.In total,eight analytical methods were developed,with the experimental data showing that all the SPME-based methods provided good analytical performance with R2 of linearities larger than 0.9925,accuracies between 81％and 118％,and good precision with an RSD％≤13％.
ABSTRACT
Liquid biopsy is a technology that exhibits potential to detect cancer early,monitor therapies,and predict cancer prognosis due to its unique characteristics,including noninvasive sampling and real-time analysis.Circulating tumor cells(CTCs)and extracellular vesicles(EVs)are two important components of circu-lating targets,carrying substantial disease-related molecular information and playing a key role in liquid biopsy.Aptamers are single-stranded oligonucleotides with superior affinity and specificity,and they can bind to targets by folding into unique tertiary structures.Aptamer-based microfluidic platforms offer new ways to enhance the purity and capture efficiency of CTCs and EVs by combining the advantages of microfluidic chips as isolation platforms and aptamers as recognition tools.In this review,we first briefly introduce some new strategies for aptamer discovery based on traditional and aptamer-based micro-fluidic approaches.Then,we subsequently summarize the progress of aptamer-based microfluidics for CTC and EV detection.Finally,we offer an outlook on the future directional challenges of aptamer-based microfluidics for circulating targets in clinical applications.
ABSTRACT
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.
ABSTRACT
With the continuous discovery and research of predictive cancer-related biomarkers,liquid biopsy shows great potential in cancer diagnosis.Surface-enhanced Raman scattering(SERS)and microfluidic tech-nology have received much attention among the various cancer biomarker detection methods.The former has ultrahigh detection sensitivity and can provide a unique fingerprint.In contrast,the latter has the characteristics of miniaturization and integration,which can realize accurate control of the detection samples and high-throughput detection through design.Both have the potential for point-of-care testing(POCT),and their combination(lab-on-a-chip SERS(LoC-SERS))shows good compatibility.In this paper,the basic situation of circulating proteins,circulating tumor cells,exosomes,circulating tumor DNA(ctDNA),and microRNA(miRNA)in the diagnosis of various cancers is reviewed,and the detection research of these biomarkers by the LoC-SERS platform in recent years is described in detail.At the same time,the challenges and future development of the platform are discussed at the end of the review.Summarizing the current technology is expected to provide a reference for scholars engaged in related work and interested in this field.