High-sensitive Detection Of Small Biomolecules Based On Split Aptamer Fragments

Detection of small biomolecules plays a key role in the field of disease forecast and care diagnostics. It has been one of the research focuses to develop excellent strategies to detect small biomolecules quickly, sensitively and accessiblely. Based on its facile synthesis and chemical modification, as well as highly specific and extraordinary target binding affinity, aptamer has been developed as a novel approach for small biomolecules detection, through varieties of signal conversion strategies. In this thesis, taking adenosine as a model biomolecule, several strategies have been developed for accessible, quick and sensitive detection, though various signal conversion modes based on nanomaterials and split aptamer fragments. It is as follows:(1) Small biomolecule detetion based on split aptemer fragments and single wall carbon nanotubeA novel small biomolecules detection strategy was developed based on split aptamer fragments and the peroxidase-like catalysis activity of single wall carbon nanotube. The method was label-free, sensitive, specific, and the detection limit was 44 nM. This work extended the application of the existing single carbon wall nanotube-aptamer system and had potential for other small biomolecules detection.(2) Small biomolecule detetion based on split aptemer fragments and light scattering of gold nanoparticlesA novel small biomolecules detection strategy was developed based on split aptamer fragments and the light scattering of gold nanoparticles. It was a one-step simple, fast and sensitive homogeneous assay, and the detection limit was 7 nM. It was help to develop convinent, rapid and sensitive methods for detection of other biomeleculars.(3) Small biomolecule detetion based on split aptemer fragments and gold nanoparticles-enhanced surface plasmon resonance(SPR) biosensorA gold nanoparticles-enhanced SPR biosensor for direct detection of adenosine was developed based on split aptamer fragments. It was highly sensitive, specific and easily regenerated, and the detection limit was 1.5 pM. It extended the application of SPR technology and had potential for detection of other small biomolecules detection.