Glycosaminoglycan Active Aptamer Equipment And Its Applied Research

Glycosaminoglycans, is also called acid mucopolysaccharides, formed by disaccharide units,and one of the units is Hexosamine.Heparin is an anticoagulant activity of glycosaminoglycans, is the world’s most effective and clinically largest amount of anticoagulant drugs, and its raw materials are mainly derived from porcine small intestinal.Currently,heparin is always used by injection which requires high purity heparin to ensure drug safety preparations.Therefore, how to research the new green, low-cost technology for purifying heparin preparations.is a key question.SELEX,,Systematic Evolution of Ligands by Exponential Enrichment,Screened with the target molecule affinity and specificity of an oligonucleotide sequence from a period of in vitro synthetic oligonucleotide library.This research uses a base of 25 random oligonucleotide sequences, then screened some oligonucleotide sequences which can combine with heparin specificity.The DNA sequences obtained by screening get on cloned, sequenced, and analyzed by DNAMAN software its primary and secondary structure, measured affinity with heparin clones.Experiment results shows that,after 15 rounds of SELEX, 20 sequences were acquired,among them three sequences appeared frequently called high frequency sequence. The secondary structure analysis showed that all the 20 sequences form the stem loop structure by the software of DNAMAN. The results means the stem loop structure is the base of aptamer binding to the target molecule.For three sequences above wo establish Enzymes linked immunosorbent assay,test result shows H29 has highest affinity for heparin,the affinity is 0.528.The aptamers obtained solve the difficulties of pharmaceutical heparin and provides a new idea and new technology.for the future.