RSC Advances
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2016
·Vol. 6
·期 25
·20867-20875
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IF 3.289
Yulan Tang,Sufang Liu,Rongbiao Pi,Zhiyi Cheng
A bi-enzyme immobilized microfluidic device was developed for the rapid enzyme inhibition assay by fluorescence detection. The micro-channels of the chip were activated by using an acidic hydrogen peroxide (H2O2) solution, followed by amination with a 3-aminopropyltriethoxysilane/methyltriethoxysilane (APTES/MTES) mixture, and then followed by glutaraldehyde grafting and subsequent covalent protein binding. The analysis was based on the oxidation of L-tyrosine to its tyrosine dimer in the presence of horseradish peroxidase (HRP) and H2O2, which has maximal excitation and emission wavelengths at 320 nm and 416 nm, respectively. H2O2 was an end product under the catalysis of acetylcholinesterase (AChE) and choline oxidase (ChO) immobilized on the inner surface of a microchip, using acetylcholine (ACh) as the enzyme substrate. Fluorescence of the dimer was directly proportional to the concentration of the H2O2 and partly reflected enzyme activity. Thus, AChE inhibition activity was indicated by a decrease in fluorescence signal detected by a microplate reader. The effects of flow velocities, reaction time and buffer systems (pH, types and concentration) on the reaction system were investigated. The utility of the developed microchip was demonstrated for AChE inhibition studies using donepezil as a model compound, which relied upon the generation of a uniform concentration of substrate and a microfluidically created concentration gradient of inhibitor using a single initial inhibitor concentration. The IC50 value of donepezil was determined and found to correlate well with that obtained in the microplate. Accordingly, the microchip can be applied to the screening of enzyme inhibitor and enzymatic reaction kinetics study, which may be useful for drug discovery and screening.
研究领域:
生物化学
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药物开发
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分析化学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
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2025
·
IF 5.1
Zirui Pang,Lulu Shi,Yao Chai,Liang Wan,Xuming Zhang,Mingyu Wang,Jifang Tao
The escalating threat of bacterial antimicrobial resistance (AMR) poses a critical challenge to global health, and in response, antibiotic susceptibility testing (AST) emerges as a vital tool for combating this issue. This study introduces an innovative self-priming digital microfluidic chip designed for rapid AST at the single-cell level, featuring an array of 1,824 chambers with integrated microvalves that facilitate effortless self-priming sample loading, eliminating the need for cumbersome external pumps. This platform has a merit of customizable pre-coating capability, allowing users to apply various antibiotics at different concentrations for multiple on-chip ASTs and streamlining the determination of minimal inhibitory concentrations (MIC) in a straightforward manner. Our experiments with Klebsiella pneumoniae ( K. pneumoniae ) demonstrated that the chip not only accurately assessed antibiotic susceptibility but also achieved results in just six hours, significantly shorter than traditional broth dilution methods. This self-priming microfluidic chip represents a leap forward in rapid AST, showcasing enhanced customization and efficiency for point-of-care testing (POCT) applications, and its potential to tackle multi-drug resistant bacterial strains makes it a promising solution for modern clinical diagnostics.
CAS / MDL:
研究领域:
微生物学
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临床诊断
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微流控技术
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DOI
高影响因子
Matter
·
2024
·
IF 17.3
Juhua Xu,Jian Qi,Chang Xu,Nan Zhang,Renshuo Wang,Xin Xu,Ke Wang,Quan Jin,Xiaolong Wang,Geyu Lu
Microwave gas sensors (MGSs) have attracted the interest of researchers because of their low power consumption, non-contact operation, and room temperature detection capabilities. However, the practical use of sensitive circuits is currently inadequate. In this context, we propose a reconfigurable rectangular waveguide microwave gas sensor (RWMGS). This RWMGS is achieved by designing a high Q-factor waveguide sensitive circuit and employing an In 2 O 3 /Al 2 O 3 monolith as the sensitive material. The prepared RWMGS exhibited an ultra-low detection limit of 10 ppb, high selectivity for NH 3 , and a remarkable sensitivity of 116.1 dB ppm −1 for concentrations lower than 50 ppb. Importantly, we introduce a chip-type sensor mode that can be used for complex system detection. This simplifies the sensing system and provides significant advantages in MGS design. These advantages can be attributed to the unique hierarchical porous structure of the monolith and the high Q-factor waveguide resonator.
研究领域:
材料科学
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传感器技术
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电子工程
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DOI
高影响因子
PHYSICS OF FLUIDS
·
2022
·Vol. 34
·期 2
·
IF 4.98
Gong Yanli,Zhang Cheng,Weng Xuan,Peng Bei,Jiang Hai
Microfluidic devices have been demonstrated to be able to concentrate low-abundance analytes and to be integrated in point of care (POC) devices for the purpose of reducing equipment size and cost; however, the complications involved in the fabrication of microfluidic chips or microelectrodes can be challenging. Here, we present a simple and effective microfluidic device monolithically integrated with liquid metal-based microelectrodes for the transportation and concentration of molecules in dilute solutions. Numerical and experimental studies were combined to validate and optimize the performance of the presented co-designing microfluidic chip featured by a double T-shaped manifold microchannel, in which the electrokinetically induced pressure-driven flow and concentration process were fully characterized. The microfluidic chip was used in a fluorimetric assay based on fluorescence resonance energy transfer between the fluorophore labeled aptamer and molybdenum disulfide nanosheets for the detection of cortisol, a stress biomarker of humans. Both experimental and numerical results show that a concentration factor up to 83-fold can be achieved within 5 min. By avoiding cumbersome fabrication processes and mechanical equipment, the proposed co-designing concentrating strategy provides insights for the fabrication of compact microfluidic chips that facilitate the miniaturization of POC devices with enhanced detection limit and sensitivity.
研究领域:
微流控技术
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生物医学工程
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分析化学
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即时诊断
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DOI
高影响因子
BIOMEDICAL MICRODEVICES
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2023
·Vol. 25
·期 1
·1-13
·
IF 2.8
Zhu Yuntian,Shi Zhengdi,Ding Weiping,Li Chengpan
Renal tubule chips have emerged as a promising platform for drug nephrotoxicity testing. However, the reported renal tubule chips hardly replicate the unique structure of renal tubules with thick proximal and distal tubules and a thin loop of Henle. In this study, we developed a fully structured scaffold-free vascularized renal tubule on a microfluidic chip. On the chip, the renal epithelial cell-laden hollow calcium-polymerized alginate tube with thick segments at both ends and a thin middle segment was U-shaped embedded in collagen hydrogel, parallel to the endothelial cell-laden hollow calcium-polymerized alginate tube with uniform tube diameter. After the alginate tubes were on-chip degraded, the renal epithelial cells and endothelial cells automatically attached to the collagen hydrogel and proliferated to form the renal tubule with proximal tubule, loop of Henle and distal tubule as well as peritubular blood vessel. We evaluated the viability of cells on the hollow alginate tubes, characterized the distribution and morphology of cells before and after the degradation of the alginate tube, and confirmed the proliferation of cells and the metabolic function of cells in terms of ATP synthesis, fibronectin secretion and VEGFR2 expression on the chip. The enhanced metabolic functions of renal epithelial cells and endothelial cells were preliminarily demonstrated. This study provides new insights into designing a more biomimetic renal tubule on a microfluidic chip.
研究领域:
生物医学工程
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组织工程
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微流控技术
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细胞生物学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2023
·
IF 8.4
Zimu Li,Min Zhu,Fang Li,Zhi Li,Anqi Zhao,Mohammad A. Haghighatbin,Hua Cui
The development of chemiluminescence (CL) sensing strategy with multiple-parameters for discrimination of small molecules remains a great challenge. Herein, a multicolor CL sensing strategy for the discrimination of five antioxidants , including dopamine, catechin, cysteine, glutathione , and thioctic acid was presented. Firstly, multilayer paper chips modified with luminol-Co(II), luminol-fluorescein-Co(II), and luminol-rhodamine B-Co(II) that can produce strong blue, green and purple colored light emission, respectively, via CL and CL resonance energy transfer (CRET) reactions were fabricated. The presence of antioxidants exhibits different inhibition or enhancement effect on the CL reactions, creating unique multicolor CL response pattern to each antioxidant. The red (R), green (G), and blue (B) channel split from the purple, green and blue CL image, respectively, generate cross-reactive sensing parameters for the discrimination of the five antioxidants. The distinct R, G, and B values of the CL images to each antioxidant are created as analytical fingerprints to identify five antioxidants by using principal component analysis and hierarchical cluster analysis. Satisfied results were obtained for discrimination antioxidant mixtures and spiked antioxidants in serum samples. Identification of 10 unknown samples resulted in 100% accuracy. This work presents the first example of multicolor CL sensing strategy for the discrimination of small molecules.
研究领域:
分析化学
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材料科学
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生物技术
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DOI
高影响因子
BIOMATERIALS
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2023
·
IF 14
Jianan Qu,Xiaoqing Wang,Yang Zhang,Ruowen Hu,Yunqi Hao,Xuechen Zhao,Chunhui Dong,Chengxi Yang,Weirong Zhang,Jingchao Sui,Yan Huang,Peng Liu,Jian Yu,Xiaofang Chen,Yubo Fan
Reprogramming of somatic cells into the pluripotent state is stochastic and inefficient using the conventional culture plates. Novel micro-culture systems employing precisely controlled biophysical cues can improve the reprogramming efficiencies dramatically. Here we perform iPSC induction on our previously developed superhydrophobic microwell array chip (SMAR-chip) where cells undergo distinctive morphology change, switching from 2D monolayers to 3D clumps, and develop into bona fide colonies in more than 90% of the microwells. The PDMS substrate, together with the microwell structure and the superhydrophobic layer constitute a well-controlled microenvironment favorable for the morphogenesis and pluripotency induction. Investigation of the molecular roadmap demonstrates that the SMAR-chip promotes the transition from the initiation phase to the maturation phase and overcomes the roadblocks for reprogramming. In addition, the SMAR-chip also promotes the reprogramming of human cells, opening our method for translational applications. In summary, our study provides a novel platform for efficient cell reprogramming and emphasizes the advantages of employing the insoluble microenvironmental cues for the precise control of cell fate conversion.
研究领域:
细胞生物学
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再生医学
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生物材料学
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DOI
PubMed
高影响因子
ELECTROPHORESIS
·
2023
·
IF 2.9
Chengzhuang Yu,Shijie Dai,Ziqi Zhang,Shanshan Li,Jingmeng Cheng,Hezhi Hu,Jayne Wu,Junwei Li
Meat adulteration detection is a common concern of consumers. Here, we proposed a multiplex digital polymerase chain reaction method and a low-cost device for meat adulteration detection. Using a polydimethylsiloxane microfluidic device, polymerase chain reaction reagents could be pump-free loaded into microchambers (40 × 40 chambers) automatically. Due to the independence of multiplex fluorescence channels, deoxyribonucleic acid templates extracted from different animal species could be distinguished by one test. In this paper, we designed primers and probes for four types of meat (beef, chicken, pork, and duck) and labeled each of the four fluorescent markers (hexachlorocyclohexane [HEX], 6-carboxyfluorescein [FAM], X-rhodamine [ROX], and cyanine dyes 5 [CY5]) on the probes. Specific detection and mixed detection experiments were performed on four types of meat, realizing a limit of detection of 3 copies/µL. A mixture of four different species can be detected by four independent fluorescence channels. The quantitative capability of this method is found to meet the requirements of meat adulteration detections. This method has great potential for point-of-care testing together with portable microscopy equipment.
研究领域:
食品科学
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分子生物学
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生物技术
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DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
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IF 4.9
Xueheng Yang,Junguang Li,Bingyan Jiang,Mingyong Zhou
Integrating membranes into microfluidic chips expands applications in many fields. A key challenge in fabrication of membrane-integrated microfluidic chips is the effective bonding of membrane and the substrate. Herein, the surface of polycarbonate track-etched membrane was modified by oxygen plasma treatment to enhance the bonding strength. Contact angle measurements confirmed the wettability of the membrane surfaces was significantly improved by plasma treatment. X-ray photoelectron spectroscopy and scanning electron microscopy analyses revealed increased oxygen incorporation onto the surface of the membranes and a linear increase in the membrane's pore size with treatment time. Two models of modification were proposed in molecular dynamics simulations to study the wetting mechanism of plasma-treat membrane at a micro scale. Burst pressure test and particle separation experiment were conducted to study the optimal parameters for plasma treatment and validate the performance of microfluidic chip. Oxygen plasma treatment effectively enhances the hydrophilicity of the membrane, generates robust intermolecular interactions and strengthens its bonding strength with the substrate.
研究领域:
材料科学
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生物医学工程
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微流控技术
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DOI
高影响因子
APPLIED OPTICS
·
2020
·Vol. 59
·期 35
·11070-11075
·
IF 1.961
Yaoyao Yin,Meng Wang,Tian Xu,Cheng Yin,Yonglong Jin
Different from ordinary planar waveguide structure, we designed a double-metal-cladding waveguide (DMCW) for easier light coupling into the guiding layer from free space. In contrast to evanescent waves in a surface plasmon polariton waveguide, an oscillating wave is generated in the guiding layer. and a similar Fabry–Perot (FP) cavity can be formed by the DMCW. In past work, the FP cavity excited by the DMCW was used to study the refractive index of light, while in this work, the FP cavity is used to excite the photothermal effect of the metal substrate. It is a good connection between light and heat. The photothermal effect is investigated to promote the galvanic replacement reaction in the substrate. Although the experiment process is destructive to the DMCW structure, a surface-enhanced Raman scattering (SERS) chip is prepared on the basis of the photothermal effect in the DMCW. It shows that the DMCW can convert the energy of incident light into thermal energy, and then prepare the SERS chip. The chip has better uniformity, stronger activity, and higher sensitivity. The results demonstrate that the morphology of the SERS substrate created via the DMCW is far more elaborate than that via the surface plasmon polariton waveguide.
研究领域:
光学
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材料科学
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纳米技术
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2025
·
IF 7.7
Yuan Gan,Shen Shen,Ning Wang,Jie Zhang
Surface-enhanced Raman scattering (SERS) technology faces several challenges in real-world applications, including low sensitivity, irreversible contamination of the substrate leading to poor cyclic stability, and difficulties in achieving integration of complex detection processes. To address these challenges, we propose a microfluidic-SERS integrated detection chip with dynamic potential modulation, enabling a complete “detection–self-cleaning–re-detection” closed-loop operation. Firstly, a high-sensitivity core-shell Ag@SiO 2 substrate was prepared using chemical reduction, achieving a detection limit of 10 −12 mol/L for Rhodamine 6 G (R6G) (AEF = 5.7 × 10 9 ). Plasma surface cleaning was then applied to bond polydimethylsiloxane (PDMS) microfluidic channels with screen-printed electrodes (SPEs), resulting in the construction of a microfluidic-SERS chip with dynamic potential modulation. By applying a positive potential (+2.0 V/10 s), target molecules were desorbed from the metal nanoparticle gaps on the SERS substrate, and a metastable metal oxide layer of a certain thickness was formed. Subsequently, a negative potential (−1.2 V/15 s) was applied to remove part of the metal oxide layer, realizing in-situ regeneration of Raman hotspots and rapidly driving probe molecule enrichment. After eight cycles of detection, the signal strength remained high. Additionally, this platform can precisely identify multi-molecule mixtures (R6G/CV/MG) and has been successfully applied to the detection of uric acid molecules. Its on-site detection capability was further validated in a portable system, providing an innovative solution for rapid detection in complex real-world environments.
研究领域:
分析化学
·
生物传感器
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纳米医学
·
即时检测
·
分子诊断
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产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2025
·Vol. 193
·期 1
·28
·
IF 5.3
Li Yixian,Yang Xiaohui,Cheng Shanshan,Mu Rongrong,Li Huiqiang,Yu Yang
Autoantibodies play a critical role in predicting diseases and monitoring therapeutic outcomes. Limitations of current autoantibody detection techniques include prolonged detection times and operational complexity. This study aims to develop a bidirectional microfluidic platform for the detection of autoantibodies. A “double inlet” and “waste outlet” structure was developed on the bidirectional lateral-flow microfluidic chip (BiLFMC). Using anti-citrullinated peptide antibodies (ACPA) as a model, this study validated the feasibility and performance advantages of the BiLFMC in the diagnosis of autoimmune disease. The BiLFMC was optimized by selecting the optimal distances between the sample inlet and waste outlet, as well as the ideal diameter for the waste outlet. The most suitable absorbent material was chosen for the waste absorbent pad. The detection and anti-interference performance of the unidirectional mode, unidirectional sequential mode, and bidirectional mode were compared, demonstrating that the bidirectional microfluidic chip significantly enhanced anti-interference capabilities. For ACPA detection, a serum sample required only a 1:100 dilution and 10 μL volume, with results available in 8 min. The coefficient of variation (CV) for repeatability ranged from 7.04% to 13.55%, while the CV for intermediate precision ranged from 11.06% to 14.49%. The limit of quantitation was 3.951 RU/mL, and the upper limit of the linear range was 500 RU/mL. When compared to ELISA results, the consistency coefficient was 0.8302. Furthermore, the BiLFMC was able to accurately distinguish samples exceeding the ELISA upper limit (> 196 RU/mL). A bidirectional microfluidic chip has been developed, incorporating indirect detection methods to enhance the anti-interference capability of the microfluidic platform. Graphical abstract
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PubMed
高影响因子
危险品化学品经营许可证（带存储）