Micromachines
·
2020
·Vol. 11
·期 2
·120
·
IF 2.524
Yujun Chen,Tao Gong,Cilong Yu,Xiang Qian,Xiaohao Wang
Simplifying tedious sample preparation procedures to improve analysis efficiency is a major challenge in contemporary analytical chemistry. Solid phase microextraction (SPME), a technology developed for rapid sample pretreatment, has flexibility in design, geometry, and calibration strategies, which makes it a useful tool in a variety of fields, especially environmental and life sciences. Therefore, it is important to study the coupling between the microfluidic electrospray ionization (ESI) chip integrated with the solid phase microextraction (SPME) module and the electrospray mass spectrometer (MS). In our previous work, we designed a solid phase microextraction (SPME) module on a microfluidic chip through geometric design. However, automation and calibration methods for the extraction process remain unresolved in the SPME on-chip domain, which will lead to faster and more accurate results. This paper discusses the necessity to design a micromixer structure that can produce different elution conditions on the microfluidic chip. By calculating the channel resistances, the microfluidic chip’s integrated module with the micromixer, SPME, and ESI emitters optimize the geometry structure. We propose the annular channel for SPME to perform the resistances balance of the entire chip. Finally, for SPME on a single chip, this work provides a quantitation calibration method to describe the distribution of the analytes between the sample and the extraction phase before reaching the adsorption equilibrium.Keywords:flow-through solid phase microextraction (SPME) on chip;quantitative analysis of flow-through solid phase microextraction (SPME);online separation;eluted;microfluidic chip;mass spectrometer (MS)
研究领域:
分析化学
·
环境科学
·
生命科学
✓ 已验证
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2017
·
IF 3.034
Agustín G. Crevillén,Mercedes de Frutos,José Carlos Diez-Masa
Isotachophoresis (ITP) coupled to zone electrophoresis (ZE), either free zone electrophoresis (FZE) or gel electrophoresis (GE), carried out mainly in capillaries and, although less frequently, also in microchips, is a powerful preconcentration and separation technique which has been successfully used for the study of many low molecular-weight analytes. However, this analytical technique has been scarcely applied for proteins separation. In this work, an on-chip transient ITP coupled to free zone electrophoresis (t-ITP-MFZE) mode with LIF detection is developed for the preconcentration and separation of the proteins α-lactalbumin and β-lactoglobulin. Firstly, for LIF detection, the proteins were off-chip fluorescently labeled with the fluorogenic reagent Chromeo P503. Then, several separation parameters in t-ITP-MFZE mode such as leading electrolyte, terminating electrolyte, separation voltage, and injection time were optimized to achieve the maximum sensitivity while maintaining an adequate resolution between α-lactalbumin and β-lactoglobulin in a single column configuration t-ITP. Using the optimized electrolytes (50 mM imidazole/HCl pH = 8 as leading electrolyte and 100 mM imidazole/12 mM HEPES pH = 8 as terminating electrolyte) separation of both proteins was achieved in less than 4 min with peak resolution of 1.5. The LODs were 55 nM and 380 nM, for α-lactalbumin and β-lactoglobulin, respectively, which are adequate for some food allergenicity studies. Finally, comparison of the optimized t-ITP-MFZE method to the equivalent MFZE method, carried out also in microchips but without the isotachophoretic preconcentration step, provided preconcentration indexes for both proteins around 10.
研究领域:
分析化学
·
蛋白质组学
·
生物技术
✓ 已验证
DOI
高影响因子
LAB ON A CHIP
·
2022
·Vol. 23
·期 2
·341-348
·
IF 7.517
Haiying Shen,Qiliang Li,Wenqi Song,Xingyu Jiang
On-chip valves can simplify a microfluidic chip and make it easy to operate. However, most on-chip valves already reported still need complicated manufacture and sophisticated supporting devices. In this work, we present a straightforward on-chip valve, which can be serially connected, to form an on-chip pump. The liquid can horizontally flow one way by the regular deformations of flexure strips in the two valves at both sides of the chamber under pressure changes in microchannels generated by repeated vertical movements of linear actuators. The volume of this system including the chip and the supporting device is 0.65 cubic decimeters, which is much smaller than that of reported systems with a volume of at least 12 cubic decimeters, and the weight of this system is only 0.56 kg, making it possible for point-of-care testing. We carry out an immunoassay of folic acid on chip, and the results show satisfactory reproducibility with acceptable coefficients of variation. We determine 163 clinical human serum samples for folic acid. Furthermore, we detect transferrin, cobalamin and folic acid simultaneously on one chip with both sandwich and competitive binding immunoassay methods. We anticipate that this on-chip valve and pump can be applied in immunoassays and other biosensing applications.
研究领域:
微流控
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生物传感
·
即时诊断
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分析化学
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-12
·
IF 17.694
Mu Zhangyan,Han Na,Xu Dan,Tian Bailin,Wang Fangyuan,Wang Yiqi,Sun Yamei,Liu Cheng,Zhang Panke,Wu Xuejun,Li Yanguang,Ding Mengning
Precise understanding of interfacial metal−hydrogen interactions, especially under in operando conditions, is crucial to advancing the application of metal catalysts in clean energy technologies. To this end, while Pd-based catalysts are widely utilized for electrochemical hydrogen production and hydrogenation, the interaction of Pd with hydrogen during active electrochemical processes is complex, distinct from most other metals, and yet to be clarified. In this report, the hydrogen surface adsorption and sub-surface absorption (phase transition) features of Pd and its alloy nanocatalysts are identified and quantified under operando electrocatalytic conditions via on-chip electrical transport measurements, and the competitive relationship between electrochemical carbon dioxide reduction (CO 2 RR) and hydrogen sorption kinetics is investigated. Systematic dynamic and steady-state evaluations reveal the key impacts of local electrolyte environment (such as proton donors with different p K a ) on the hydrogen sorption kinetics during CO 2 RR, which offer additional insights into the electrochemical interfaces and optimization of the catalytic systems.
研究领域:
电化学
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催化
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材料科学
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能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Biomaterials Science & Engineering
·
2023
·
IF 5.8
Guowei Wang,Chengpan Li,Chunguang Miao,Shibo Li,Bensheng Qiu,Weiping Ding
With the emergence of various cutting-edge micromachining technologies, lab on a chip is growing rapidly, but it is always a challenge to realize the on-chip separation of living cells from cell samples without affecting cell activity and function. Herein, we report a novel on-chip label-free method for sorting living and dead cells by integrating the hypertonic stimulus and tilted-angle standing surface acoustic wave (T-SSAW) technologies. On a self-designed microfluidic chip, the hypertonic stimulus is used to distinguish cells by producing volume differences between living and dead cells, while T-SSAW is used to separate living and dead cells according to the cell volume difference. Under the optimized operation conditions, for the sample containing 50% of living human umbilical vein endothelial cells (HUVECs) and 50% of dead HUVECs treated with paraformaldehyde, the purity of living cells after the first separation can reach approximately 80%, while after the second separation, it can be as high as 93%; furthermore, the purity of living cells after separation increases with the initial proportion of living cells. In addition, the chip we designed is safe for cells and can robustly handle cell samples with different cell types or different causes of cell death. This work provides a new design of a microfluidic chip for label-free sorting of living and dead cells, greatly promoting the multi-functionality of lab on a chip.
研究领域:
微流控技术
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生物医学工程
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细胞生物学
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芯片实验室技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2024
·Vol. 191
·期 8
·1-12
·
IF 5.3
He Qian,Chen Qun,Lian Lijin,Qu Jiuxin,Yuan Xi,Wang Chuhui,Xu Lidan,Wei Jiazhang,Zeng Shaoling,Yu Dongmei,Dong Yuhan,Zhang Yongbing,Deng Lin,Du Ke,Zhang Canyang,Pandey Vijay,Gul Ijaz,Qin Peiwu
The CRISPR/Cas13 nucleases have been widely documented for nucleic acid detection. Understanding the intricacies of CRISPR/Cas13’s reaction components is pivotal for harnessing its full potential for biosensing applications. Herein, we report on the influence of CRISPR/Cas13a reaction components on its trans-cleavage activity and the development of an on-chip total internal reflection fluorescence microscopy (TIRFM)-powered RNA sensing system. We used SARS-CoV-2 synthetic RNA and pseudovirus as a model system. Our results show that optimizing Mg 2+ concentration, reporter length, and crRNA combination significantly improves the detection sensitivity. Under optimized conditions, we detected 100 fM unamplified SARS-CoV-2 synthetic RNA using a microtiter plate reader. To further improve sensitivity and provide a new amplification-free RNA sensing toolbox, we developed a TIRFM-based amplification-free RNA sensing system. We were able to detect RNA down to 100 aM. Furthermore, the TIRM-based detection system developed in this study is 1000-fold more sensitive than the off-coverslip assay. The possible clinical applicability of the system was demonstrated by detecting SARS-CoV-2 pseudovirus RNA. Our proposed sensing system has the potential to detect any target RNA with slight modifications to the existing setup, providing a universal RNA detection platform. Graphical Abstract
CAS / MDL:
研究领域:
生物传感
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分子生物学
·
纳米技术
·
病毒学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Micromachines
·
2018
·Vol. 9
·期 5
·212
·
IF 2.222
Hangbin Tang,Quan Yu,Xiang Qian,Kai Ni,Xiaohao Wang
Microfluidic chips coupling with mass spectrometry (MS) will be of great significance to the development of relevant instruments involving chemical and bio-chemical analysis, drug detection, food and environmental applications and so on. In our previous works, we proposed two types of microfluidic electrospray ionization (ESI) chip coupling with MS: the two-phase flow focusing (FF) ESI microfluidic chip and the corner-integrated ESI emitter, respectively. However the pretreatment module integrated with these ESI emitters is still a challenging problem. In this paper, we concentrated on integrating the solid phase micro-extraction (SPME) module with our previous proposed on-chip ESI emitters; the fabrication processes of such SPME module are fully compatible with our previous proposed ESI emitters based on the multi-layer soft lithography. We optimized the structure of the integrated chip and characterized its performance using standard samples. Furthermore, we verified its abilities of salt removal, extraction of multiple analytes and separation through on-chip elution using mimic biological urine spiked with different drugs. The results indicated that our proposed integrated module with ESI emitters is practical and effective for real biological sample pretreatment and MS detection.Keywords:microfluidic chip;solid phase extraction;mass spectrometry;two-phase flow focusing;integrated electrospray ionization (ESI) emitter;on-chip solid phase micro-extraction (SPME) module;pretreatment technology
研究领域:
分析化学
·
生物医学工程
·
仪器科学与技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Bioactive Materials
·
2024
·
IF 18
Yu-hong Wang,Ting-ting Liu,Yan-ping Guo,Shuo-ji Zhu,Zi-ming Liao,Jia-mei Song,Xi-ming Zhu,Jia-liang Liang,Moussa Ide Nasser,Nan-bo Liu,De-hua Chang,Ping Zhu,Bin Yao
The preclinical evaluation of drug-induced cardiotoxicity is critical for developing novel drug, helping to avoid drug wastage and post-marketing withdrawal. Although human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) and the engineered heart organoid have been used for drug screening and mimicking disease models, they are always limited by the immaturity and lack of functionality of the cardiomyocytes. In this study, we constructed a Cardiomyocytes-on-a-Chip (CoC) that combines micro-grooves (MGs) and circulating mechanical stimulation to recapitulate the well-organized structure and stable beating of myocardial tissue. The phenotypic changes and maturation of CMs cultured on the CoC have been verified and can be used for the evaluation of cardiotoxicity and cardioprotective drug responses. Taken together, these results highlight the ability of our myocardial microarray platform to accurately reflect clinical behaviour, underscoring its potential as a powerful pre-clinical tool for assessing drug response and toxicity.
研究领域:
生物医学工程
·
药理学
·
干细胞研究
·
药物开发
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2023
·
IF 4.1
Yangkun Sun,Shengli Ruan,Yuanyuan Zhou,Linhao Zhao,Wenjing Xiong,Chuhui Lin,Jingjing Kuang,Fanghong Ning,Min Zhang,Hongyang Zhang,Ping Hu
In this paper, we designed and manufactured a reliable magnetic solid phase extraction (MSPE) microfluidic chip for determination of polycyclic aromatic hydrocarbons (PAHs) in water combined with gas chromatography-mass spectrometry. Sample loading, washing and elution are implemented with microinjection pump and integrated on a single chip, which reduced manual operation. Magnets were used to fix octadecyl/phenyl bifunctional Fe 3 O 4 @SiO 2 extractant to avoid the design of weir structure in extraction chamber. The whole microfluidic chip was simple and low cost. Based on the microfluidic chip extraction platform, the on-chip MSPE method for the determination of PAHs was optimized and established. The results showed that this method required only 2 mL of sample, 2 mg of extractant, and 50 μL of elution organic solvent for whole on-chip MSPE process, which was environmentally friendly and consistent with green chemistry. Method verification results were displayed which the linear range of five PAHs was between 1-100 ng/mL with good linearity (R 2 ≥ 0.9985), and the detection limits (S/N = 3) were 0.08–0.26 ng/mL. The RSDs of intra-day precision (n=6) and inter-day precision (n=9) for PAHs were less than 6.1 % and 7.2 %, respectively. Enrichment factors were determined to be 31.3–37.7. The recoveries of river water, tap water, bottle water, waste water and urine at three spiked levels were in the range of 89.9% to 113.7% and the matrix effect values were between 83.8% to 109.6%. The extraction platform has the advantages of accurate analysis, simple design and cost-effective, which is conducive to the widespread use of microfluidic chips
研究领域:
分析化学
·
环境科学
·
微流控技术
·
色谱法
·
质谱法
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）