The Application Of Micro/nano Technology In Dna Detection And Antibody Purification

At present, the micro and nano technology have been more and more used in the area of analysis and detection. Nanomaterials play an important role in the diagnosis and treatment of disease combinding with DNA. Based on a series of unique physical and chemical properties of gold nanoparticles and quantum dots, especially its biocompatibility, they had been widely used in the field of bioanalysis. Polymerase chain reaction is a specific nucleic acid sequence amplification in vitro, which is one of basic work in the modern molecular biology experiments, playing an important role in the areas such as life sciences, genetics and medicine. In our work, the gold nanoparticles and quantum dots were used in the PCR process, achieving the interface PCR amplification, and a new DNA detection method was established.Gold nanoparticles had a fluorescence quenching effect on the quantum dots within a certain distance. The forward and reverse primers of different amplification length were designed and conjugated to the surface of the GNPs and QDs respectively. Under the effect of PCR, the GNPs and QDs were linked together by the double stranded DNA (dsDNA), which induced the fluorescence quenching of the QDs. And the fluorescence quenching intensity was determined by the distance between the GNPs and QDs, which was depended on the length of the dsDNA. As a proof-of-concept research, the detection of the DNA length range from 50 to 1000 base pairs was realized by the quantitative correlationship between the quenched fluorescence intensity and the length of DNA. The conclusion was that with the increasing of the distance (50 to 1003bp) between two particles, the fluorescence quenching effect weakened, the standard curve for DNA detection was established, and used for the detection of pathogenic microorganisms.Polystyrene is an excellent carrier. The introduction of carboxyl, amino, hydroxyl or other functional groups on the surface of polystyrene microsphere, it could be used for the immobilization of biological macromolecules such as proteins, and small organic molecules. In our work, the purification effect of antibody to clenbuterol was studied with the method of amino-polystyrene microspheres, and compared with ammonium sulfate precipitation method, detected with ELISA. The results showed that the titers of the former was 218700, the latter was 72900.