A review on cell-based models of human liver disease in vitro / 生物医学工程学杂志

Unhealthy diet, habits and drug abuse cause a variety of liver diseases, including steatohepatitis, liver fibrosis, liver cirrhosis and liver cancer, which seriously affect human health. The fabrication of highly simulated cell models in vitro is important in the treatment of liver diseases and drug development. This article summarized the common strategies for the construction of liver pathology models

Development of Android Platform Based Portable Trace Heavy Metal Ions Detector / 分析化学

Based on the Android platform, a portable electrochemical analyzer was designed for the detection of heavy metal ions. Its output voltage range was ±3 V with accuracy of 0. 1% and resolution of <1 mV. The current acquisition range was±10 mA with accuracy of 0. 1% and the minimum resolution of 10 pA. With the human-computer interaction advantage of Android smart devices, professional and fast detection mode which could meet the needs of professional and ordinary users respectively were developed to simplify the complex process of electrochemical detection and analysis. Some common heavy metal ions including copper, cadmium, lead and mercury were detected with this detector. The results of linearity, repeatability and accuracy were satisfactory.

Membrane transfer-based colorimetric DNA detection using enzyme modified gold nanoparticles / 生物工程学报

We report here a novel membrane transfer-based DNA detection method, in which alkaline phosphatase labeled gold nanoparticle (AuNP) probes were used as a means to amplify the detection signal. In this method, the capture probe P1, complimentary to the 3' end of target DNA, was immobilized on the chip. The multi-component AuNP probes were prepared by co-coating AuNPs with the detecting probe P2, complimentary to the 5' end of target DNA, and two biotin-labeled signal probes (T10 and T40) with different lengths. In the presence of target DNA, DNA hybridization led to the attachment of AuNPs on the chip surface where specific DNA sequences were located in a "sandwich" format. Alkaline phosphatase was then introduced to the surface via biotine-streptavidin interaction. By using BCIP/NBT alkaline phosphatase color development kit, a colorimetric DNA detection was achieved through membrane transfer. The signal on the membrane was then detected by the naked eye or an ordinary optical scanner. The method provided a detection of limit of 1 pmol/L for synthesized target DNA and 0.23 pmol/L for PCR products of Mycobacterium tuberculosis 16S rDNA when the ratio of probes used was 9:1:1 (T10:T40:P2). The method described here has many desirable advantages including high sensitivity, simple operation, and no need of sophisticated equipment. The method can be potentially used for reliable biosensings.

Patterning different cells based on microfluidics and self-assembled monolayers / 生物工程学报

The ability to pattern multiple cells through precise surface engineering of cell culture substrates has promoted the development of cellular bioassays, such as differentiation, interaction and molecular signaling pathways. There are several well developed ways to pattern cells. This report describes a method for patterning multiple types of cells based on microfluidics and self-assembled monolayers. We developed two types of micro-dam structures by soft-lithography to locate cells precisely and modified the substrate by a kind of self-assembled monolayer with property of electrochemical desorption to confine cells in specific areas. Finally we could pattern an array of two different types of cells closely and precisely. Cells were confined in specific areas but still shared the same microenvironment, so they could interact through soluble molecules. The substrate was transparent and open, so we could easily apply several instruments for research. With these merits, this cell chip is appropriate for investigating the interaction between different types of cells.

Microfluidic cell culture array chip for drug screening assays / 生物工程学报

We developed a novel microfluidic cell chip, which enabled drug delivery, fluid control and cell co-culture. The device consisted of an array of 6x6 cell culture chambers, a drug gradient generator and fluidic control valves. Micro-dam structures of the chambers were able to trap cells while loading and drug gradient network generated drug gradient of 6 different concentrations. Also we applied hydraulic valves to control the microfluid and simulate the microenvironment of cells. We had investigated the viability of co-culturing cells in the chip and the ability for drug screening. This microfluidic cell chip has the potential in cell-based research of high throughput drug screening.

Fabrication and application of a novel cell culture microchip / 生物工程学报

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.

The application of flexible neural microelectrode on retinal prosthesis / 生物医学工程学杂志

The latest development and the merit of using flexible neural microelectrodes are mainly reported in the paper, in which the properties of based-material, the micro-structure of neural microelectrodes and the method about how to test the microelectrodes are also included.

Influence of labeled primer and labeled dUTP assays on the signal intensity of the chip for the detection of HBV gene polymorphism / 中华实验和临床病毒学杂志

<p><b>BACKGROUND</b>To evaluate the influence of assays with primer labeled with fluorochrome (Cy5) and dUTP labeled with Cy5 on the signal intensity of the chip for detection of hepatitis B virus (HBV) gene polymorphism.</p><p><b>METHODS</b>The P-region and pre-C/C-region of HBV gene were amplified by polymerase chain reaction (PCR) with Cy5 labeled primer or Cy5 labeled dUTP. The amplicons of the two assays were hybridized with chips, scanned and analyzed by computer software for the detection of HBV gene polymorphism.</p><p><b>RESULTS</b>The signal intensity of assay with Cy5 labeled dUTP was slightly higher than that of assay with Cy5 labeled primer, but non?specific signal intensity of the assay with Cy5 labeled dUTP was higher. The result of 42 samples showed that there was no significant difference between the two assays, and that both had a good repeatability and CV value (15%-20%).</p><p><b>CONCLUSIONS</b>The assay with Cy5 labeled primer may replace the assay with Cy5 labeled dUTP as a routine method to detect HBV gene polymorphism, and it is simpler and cheaper.</p>

Manufacture of Complementary DNA Arrays on Amino-modified Slides / 生物化学与生物物理进展

The use of rnicroarrays of oligonucleotides or cDNA is considered to be a promising approach for DNA and RNA sequence analysis, diagnostics of genetic diseases, gene polymorphism studies and analysis of gene expression. To manufacture cDNA microarrays the samples were printed onto glass microscope slides treated with poly-L-lysine, and then the slides were processed by heat and UV light treatment to attach the cDNA sequence to the glass surface. But the immobilization efficiency of cDNA on the glass surface was low. A simple procedure for manufacture cDNA microarrays on a slide treated with 3-aminopropyltrimethoxysilane is described. The efficiency for attaching cDNA to the amino-modified slides is greater than that to the slides treated with poly-L-lysine. The cDNA microarray made by the amino-modified slides is stable for use in 80℃, 75 % humidity, 3 600Lx light, exposure in air, respectively.

Rapid detection of clinical pathogenic bacteria and antimicrobial-resistant genes using DNA chip / 中华传染病杂志

Objective To detect the clinical pathogenic bacteria and antimicrobial-resistant genes quickly and sensitively using DNA chip.Methods Based on the analysis of 23S rRNA gene se- quences and other genes sequences associated with antimicrobial resistance(SHV＜CTX_M),oligo nucleotide microarray was designed according to different bacteria and antimicrobial-resistant genes. The DNA fragments were amplified by labeling Cy5 fluorescence and detect clinical pathogenic bacte- rias and antimicrobial-resistant genes by hybridization.Results The result of detection(10~3-10~6 bac- teria/ml)was consistent with that of some documents in domestic and overseas under ideal circum- stances of detecting bacteria genomic DNA by the Reagent Box.And it was specific and reproducible when the detection system were evaluated with some clinical isolates and drug-resistant standard strain.DNA chip could identify 16 species and 7 generics including common diverse clinical pathogenic bacteria,and could detect the drug-resistant of extended spectrum?lactamase gene simultaneously. Conclusions The methods that we have established DNA chip is a sensitive,specific and reproducable tool for supplying routine methods.

Rapid Detection of Mutations of Neisseria gonorrhoeae gyrA Gene Using DNA Chip / 中华皮肤科杂志

Objective To develop a new method-DNA chip to be used for rapid detection of mutations of Neisseria gonorrhoeae gyrA gene. Methods Probes were designed according to the sequence of Neisseria gonorrhoeae gyrA genes, and DNA chip was fabricated accordingly. DNA fragment which contains gyrA gene mutation was amplified using PCR technique, labeled with Cy5 fluorescence, and then hybridized with DNA chip. Results of DNA sequencing were used as the control. Results All of the 50 urogenital swab specimens were detected using DNA chip. The consistency between the DNA chip and drug sensitivity test, and between the DNA chip and DNA sequencing were 100% and 98%, respectively. Conclusions DNA chip is a rapid technique with high sensitivity and specificity for the detection of mutations of Neisseria gonorrhoeae gyrA gene. This method can be used for the detection of drug resistance in clinical practice.

Detection of Pathogens of Urogenital Infections and Their Drug-resistant Types by a DNA Chip / 中华皮肤科杂志

0.8). Conclusions This DNA chip combined with multiplex PCR is a rapid diagnostic assay with high specificity and sensitivity for the detection of Neisseria gonorrhoeae, Chlamydia trachomatis and Ureaplasma Urealyticum and their drug-resistance, and may be applied in the diagnosis of urogenital infections.