1. The concept of liquid phase chip
Liquid-phase chip, also known as suspension array and flow fluorescence technology, is a multifunctional biochip platform developed based on the multifunctional flow array instrument (Luminex 100TM) developed by Luminex Company in the United States. It is usually used for immunoassay, nucleic acid research, enzyme Studies on biological analysis, receptor and ligand recognition analysis, etc. It is also the only biochip platform recognized by authoritative institutions and the medical community for clinical diagnosis. Liquid chip is a new concept of biological chip. The core of the technology is to encode tiny polystyrene beads (5.6um) with fluorescent dyeing, and then covalently cross-link the microspheres of each color (or fluorescently encoded microspheres) for specific detection. Probes, antigens or antibodies of substances. When applying, first mix the encoded microspheres for different detection substances, and then add a small amount of the sample to be tested. In the suspension, the target molecules and the molecules cross-linked on the surface of the microspheres are specifically combined, which can be completed simultaneously in one reaction well. Up to 100 different biological responses. Finally, LuminexTM analysis software is used for analysis. The instrument uses two laser beams to identify the coding microspheres and detect the fluorescence intensity of the reporter molecules on the microspheres. Because molecular hybridization or immunoreaction is carried out in suspension solution, the detection speed is extremely fast, and up to 100 indicators can be detected simultaneously in a micro liquid reaction system.
2. Advantages of liquid phase chips
(1) One test, 100 indicators;
(2) It can detect both protein and nucleic acid;
(3) It can be used both clinically and scientifically.
3. Application of liquid phase chip
(1) DNA hybridization analysis
gene expression profiling
(2) Immunological analysis
Protein-Protein Interaction Analysis
Protein-DNA Interaction Analysis
4. Application examples
The Liquichip LC system is a highly flexible multivariate analysis platform that can be applied to a variety of protein analyses in scientific research, clinical research and pharmaceutical research.
Dr. Richard et al. of St. Jude Children’s Research Hospital in the United States used the liquid phase to simultaneously measure 15 different cytokines in a 100 μL sample. The results indicated that there were significant differences in the expression levels of certain cytokines between T helper cell types 1 and 2. During the assay, Dr. Richard labeled 15 different cytokine antibodies on 15 different spherical substrates, mixed them and added them to a reaction system to measure 15 cytokines in the same sample. At the same time, 15 cytokines were detected by ELISA. After comparing the two sets of results, it is found that the trend is basically the same, but the liquid phase can detect multiple molecules at the same time, with better sensitivity and reliability, and simpler operation. In this way, only a small amount of sample is needed, and the required data can be obtained in a relatively short period of time.