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 ; Immunoassay ; methods ; Microfluidic Analytical Techniques ; trends ; Microfluidics ; trends

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 ; isolation & purification ; Microfluidic Analytical Techniques ; Microfluidics ; instrumentation

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 ; Humans ; Microfluidic Analytical Techniques ; Microfluidics

Microfluidics is the science and technology to manipulate small amounts of fluids in micro/nano-scale space. Multiple modules could be integrated into microfluidic device, and due to its advantages of microminiaturization and controllability, microfluidics has drawn extensive attention since its birth. In this paper, the literature data related to microfluidics research from January 1, 2006 to December 31, 2021 were obtained from Web of Science Core Collection database. CiteSpace 5.8.R3 software was used for bibliometrics analysis, so as to explore the research progress and development trends of microfluidics research at home and abroad. Based on the analysis of 50 129 articles, it could be seen that microfluidics was a hot topic of global concern, and the United States had a certain degree of authority in this field. Massachusetts Institute of Technology and Harvard University not only had a high number of publications, but also had strong influence and extensive cooperation network. Combined with ultrasonic, surface modification and sensor technology, researchers constructed paper-based microfluidic, droplet microfluidic and digital microfluidic platforms, which were applied in the field of immediate diagnosis, nucleic acid and circulating tumor cell analysis of in vitro diagnosis and organ-on-a-chip. China was one of the countries with a high level of research in the field of microfluidics, while the industrialization of high-end products needed to be improved. As people's demand for disease risk prediction and health management increased, promoting microfluidic technological innovation and achievement transformation is of great significance to safeguard people's life and health.
China ; Humans ; Microfluidic Analytical Techniques ; Microfluidics ; Oligonucleotide Array Sequence Analysis

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.
Animals ; Drug Evaluation, Preclinical ; Humans ; Lung ; Microfluidic Analytical Techniques ; Microfluidics

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.
Humans ; Microfluidics ; Immunoglobulin G ; Kidney ; Microfluidic Analytical Techniques

Microfluidic chip is a novel technology platform, in which microchannels are fabricated in different materials. The ability to precisely control the microflows makes it possible to mimic the microenvironment of cells in physiological or pathological states, which provides many distinct advantages for cell research. In this paper are reviewed the design and fabrication of microfluidic chip, the application of microfluidic chip in cell culture and cell researches; the enormous advantages of microfluidic chips in precise experimental control of the cellular microenvironment are introduced.
Cell Adhesion ; Cell Culture Techniques ; Cell Movement ; Cells, Cultured ; Cellular Microenvironment ; Humans ; Microfluidic Analytical Techniques ; methods

In this article, a cell culture microchip was fabricated on the SU-8 mold based on polymer-MEMS process. In the microchip, the cell culture area was separated with microchannel by a microgap, which kept the cell culture area independent, but also regulated the micro-environment of extracellular matrix by the microfluidic flow. The cell culture microchip provided a new platform for cell research.
3T3 Cells ; Animals ; Cell Culture Techniques ; methods ; Mice ; Microfluidic Analytical Techniques ; methods

Laser scanning confocal microscope (LSCM) is currently the only equipment to observe fluorescence. However, this technique has disadvantages such as high cost and long test process. In this study, we developed a new system of laser-induced fluorescence (LIF) for microfluidic chip applied to detecting the expression of green fluorescent protein (GFP) in Bacillus subtilis. This novel system was comprised of laser device, optics unit, microfluidic chip, photomultiplier and computer treatment unit. The tests indicated that microfluidic chip could detect the expression of GFP as sensitively as LSCM in Bacillus subtilis. Moreover, this LIF detection system could instead of PCR to identify the positive clone in this special case. Nevertheless, the LIF system only was suitable to detect the fluorescent strength of GFP, and could not meet the request of some cases for example protein location. Therefore, this system will be applied in environmental detection with microbe, drug discovery and other cases.
Bacillus subtilis ; isolation & purification ; metabolism ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Microfluidic Analytical Techniques ; methods

Microfluidics deals with the manipulation of fluidics in the structure with dimensions of micrometers or nanometers. As an emerging field, microfluidics has numerous advantages, such as controllable fluid flow and reduced reagents consumption. Recently, microfluidic has been applied into the area of cell transfection, providing opportunities to investigate cell transfection process on microscale. This review summarizes recent technical development of cell transfection based on microfluidics, including transfeceted microarray, transfecetion established in miniaturization flowing space, microdrops, microinjection and microfluidic electroporation. The factors that affect the transfection efficiency and improvement approaches are also discussed.
Electroporation ; Microfluidic Analytical Techniques ; instrumentation ; Miniaturization ; Oligonucleotide Array Sequence Analysis ; Transfection