1.Technology development and instrumentation of a high-throughput and automated microbial microdroplet culture system for microbial evolution and screening.
Xiaojie GUO ; Liyan WANG ; Chong ZHANG ; Xin-Hui XING
Chinese Journal of Biotechnology 2021;37(3):991-1003
Since microdroplets are able to be generated rapidly in large amount and each droplet can be well controlled as an independent micro-cultivator, droplet microfluidic technology can be potentially used in the culture of microorganisms, and provide the microbial culture with high throughput manner. But its application mostly stays in the laboratory-level building and using for scientific research, and the wide use of droplet microfluidics in microbial technology has been limited by the key problems that the operation for microdroplets needs high technical requirements with wide affecting factors and the difficulties in integration of automatic microdroplet instrumentation. In this study, by realizing and integrating the complicated operations of droplet generation, cultivation, detection, splitting, fusion and sorting, we design a miniaturized, fully automated and high-throughput microbial microdroplet culture system (MMC). The MMC can be widely used in microbial growth curve test, laboratory adaptive evolution, single factor and multi-level analysis of microbial culture, metabolite detection and so on, and provide a powerful instrument platform for customized microbial evolution and screening aiming at efficient strain engineering.
Industrial Development
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Microfluidics
2.Paper-Based Analytical Device for Quantitative Urinalysis.
Seong Geun JEONG ; Jongmin KIM ; Jin Oh NAM ; Young Shin SONG ; Chang Soo LEE
International Neurourology Journal 2013;17(4):155-161
Paper-based analytical devices are fluidic chips fabricated with extremely inexpensive materials, namely paper, thereby allowing their use as a zero-cost analytical device in third-world countries that lack access to expensive diagnostic infrastructures. The aim of this review is to discuss: (1) microfluidic paper-based analytical devices (microPADs) for quantitative analysis, (2) fabrication of two- or three-dimensional microPADs, (3) analytical methods of microPADs, and (4) our opinions regarding the future applications of microPADs for quantitative urinalysis.
Developing Countries
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Methods
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Microfluidics
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Urinalysis*
3.Tactic movement of microalgae and its application in targeted transport: a review.
Yuanyuan LIU ; Weiyang ZENG ; Ru CHEN ; Yunlong GE ; Lihan ZI ; Jun YANG ; Fantao KONG
Chinese Journal of Biotechnology 2022;38(2):578-591
Microalgae are a group of photosynthetic microorganisms, which have the general characteristics of plants such as photosynthesis, and some species have the ability of movement which resembles animals. Recently, it was reported that microalgae cells can be engineered to precisely deliver medicine-particles and other goods in microfluidic chips. These studies showed great application potential in biomedical treatment and pharmacodynamic analysis, which have become one of the current research hotspots. However, these developments have been rarely reviewed. Here, we summarized the advances in manageable movement exemplified by a model microalgae Chlamydomonas reinhardtii based on its characteristics of chemotaxis, phototaxis, and magnetotaxis. The bottlenecks and prospects in the application of microalgae-based tactic movement were also discussed. This review might be useful for rational design and modification of microalgal manageable movement to achieve targeted transport in medical and other fields.
Chlamydomonas reinhardtii
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Microalgae
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Microfluidics
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Photosynthesis
4.Extraction of exosome by gel electrophoresis microfluidic chip and determination of miRNA-21 in exosome of human plasma.
Dan LUO ; Fengying RAN ; Lun WU ; Juan ZHANG ; Fangling REN ; Jingjian LIU ; Binqiang ZHANG ; Qinhua CHEN
Chinese Journal of Biotechnology 2021;37(2):663-672
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.
Exosomes
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Humans
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MicroRNAs/genetics*
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Microfluidics
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Plasma
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Ultracentrifugation
5.Research Progress of Application of Microfluidics Techniques in Cryopreservation.
Nanfeng ZHOU ; Yun YANG ; Xinli ZHOU
Journal of Biomedical Engineering 2015;32(3):702-706
Microfluidics technology may be an effective method to solve some problems in cryopreservation. This review presents the research progress of microfluidics technology in the field of cell membrane transport properties, cryoprotectant addition and washout and the vitrification for cryopreservation of biological materials. Existing problems of microfluidics technology in the application of cryopreservation are summarized and future research directions are indicated as well.
Cell Membrane
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Cryopreservation
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Cryoprotective Agents
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Membrane Transport Proteins
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Microfluidics
6.Research progress in microfluidic immunoassay chip.
Journal of Biomedical Engineering 2007;24(4):928-931
In recent 10 years, microfluidic technology has developed rapidly. Hence the speed of analysis can be upgraded, the performance be improved and the consumption of sample and reagent be reduced. In this review, we introduce the design, fabrication and application of microfluidic immunoassay chip.
Humans
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Immunoassay
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methods
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Microfluidic Analytical Techniques
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trends
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Microfluidics
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trends
7.Micro-droplet characterization and its application for amino acid detection in droplet microfluidic system.
Huiling YUAN ; Libing DONG ; Ran TU ; Wenbin DU ; Shiru JI ; Qinhong WANG
Chinese Journal of Biotechnology 2014;30(1):139-146
Recently, the droplet microfluidic system attracts interests due to its high throughput and low cost to detect and screen. The picoliter micro-droplets from droplet microfluidics are uniform with respect to the size and shape, and could be used as monodispensed micro-reactors for encapsulation and detection of single cell or its metabolites. Therefore, it is indispensable to characterize micro-droplet and its application from droplet microfluidic system. We first constructed the custom-designed droplet microfluidic system for generating micro-droplets, and then used the micro-droplets to encapsulate important amino acids such as glutamic acid, phenylalanine, tryptophan or tyrosine to test the droplets' properties, including the stability, diffusivity and bio-compatibility for investigating its application for amino acid detection and sorting. The custom-designed droplet microfluidic system could generate the uniformed micro-droplets with a controllable size between 20 to 50 microm. The micro-droplets could be stable for more than 20 h without cross-contamination or fusion each other. The throughput of detection and sorting of the system is about 600 micro-droplets per minute. This study provides a high-throughput platform for the analysis and screening of amino acid-producing microorganisms.
Amino Acids
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isolation & purification
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Microfluidic Analytical Techniques
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Microfluidics
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instrumentation
8.Application and prospect of microfluidic chip in central nervous system diseases.
Chinese Journal of Biotechnology 2019;35(3):396-403
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.
Central Nervous System Diseases
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Humans
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Microfluidic Analytical Techniques
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Microfluidics
9.Development and application of a droplet-based microfluidic high-throughput screening of Pichia pastoris.
Tong LÜ ; Ran TU ; Huiling YUAN ; Hao LIU ; Qinhong WANG
Chinese Journal of Biotechnology 2019;35(7):1317-1325
Pichia pastoris is one of the most convenient and widely used heterologous protein expression systems. To further improve its ability to express heterologous proteins, we developed a high-throughput P. pastoris screening method based on droplet microfluidic and demonstrated the method by screening and obtaining mutants with enhanced xylanase expression and secretion abilities. We used PCR (Polymerase Chain Reaction) amplification to obtain a fusion fragment of xylanase xyn5 gene and green fluorescent protein gfp gene, and cloned this fragment into pPIC9K, the expression vector of Pichia pastoris, to construct the plasmid pPIC9K-xyn5-gfp that recombined the DNA fragments of xylanase and green fluorescent protein. After this plasmid entered P. pastoris GS115 by electroporation, the P. pastoris SG strain that could express xylanase and green fluorescent protein was obtained. The above-said strains were then mutagenized by atmospheric room temperature plasma and subsequently encapsulated to form single-cell droplets. After 24-hour cultivation of the droplets, microfluidic screening was carried out to obtain the mutant strain with high xylanase expression for further construction and screening of the next mutagenesis library. After five rounds of droplet microfluidic screening, a highly productive strain P. pastoris SG-m5 was obtained. The activity of the expressed xylanase was 149.17 U/mg, 300% higher than that of those expressed by the original strain SG. This strain's ability to secrete heterologous protein was 160% higher than that of the original strain. With a screening throughput of 100 000 strains per hour, the high-throughput P. pastoris screening system based on single-cell droplet microfluidic developed by the present study screens a library with million strains in only 10 hours and consumes only 100 μL of fluorescent reagent, thus reducing the reagent cost by millions of times compared with the traditional microplate screening and more importantly, providing a novel method to obtain P. pastoris with high abilities to express and secret heterologous proteins by efficient and low-cost screening.
Microfluidics
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Mutagenesis
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Pichia
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Plasmids
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Polymerase Chain Reaction
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Recombinant Proteins
10.Analytical Performance and Reference Interval of a Microfluidic Viscometer, Viscore-300 for the Measurement of Whole Blood Viscosity
Yong Jun KWON ; Jun Hyung LEE ; James MOON ; Hye Ran KIM ; Hyun Jung CHOI ; Soo Hyun KIM ; Yonggwan WON ; Myung Geun SHIN
Laboratory Medicine Online 2018;8(1):1-6
BACKGROUND: Whole blood viscosity (WBV) refers to the internal resistance that occurs when blood flows through blood vessels. WBV is known to be related to many diseases including cardiovascular and neurovascular diseases. We have investigated the analytical performance and established reference intervals for a newly developed microfluidic viscometer, Viscore-300 (NanoBiz, Korea), used for the measurement of WBV. METHODS: We performed a precision test of 240 measurements over 20 days using three control materials. For evaluation of repeatability, a total of 60 WBV measurements were made in 3 whole blood samples 20 times a day. A total of 100 whole blood samples were used to evaluate the accuracy of the Viscore-300 in comparison to a rotating viscometer, DV3T (Brookfield, USA), in accordance with the the Clinical and Laboratory Standards Institute's guidelines. To establish the reference intervals, 122 healthy individuals were enrolled in this study. RESULTS: The precision and repeatability results showed that the CV was less than 5% for three samples and two shear rates. In the accuracy test, the mean differences between two viscometers were 0.09 cP (0.9%) and −0.07 cP (−1.4%) at shear rates of 10 s−1 and 300 s−1, respectively. The reference intervals of WBV for men were 6.88–13.52 cP at 10 s−1 and 4.32–6.43 cP at 300 s−1; those of women were 5.74–13.29 cP at 10 s−1 and 3.60–6.12 cP at 300 s−1. CONCLUSIONS: Viscore-300 showed excellent precision and accuracy and it might be a good instrument for reporting WBV quickly and accurately.
Blood Vessels
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Blood Viscosity
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Female
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Humans
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Male
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Microfluidics