论文部分内容阅读
Due to its distinct advantages of high signal-to-noise ratio,low sample consumption and improved sensitivity,single-molecule detection has become a promising approach in the research of chemical analysis,medical diagnosis and dynamic study of biological processes.The semiconductor quantum dots are considered as the valuable supplement to the conventional fluorescent proteins and organic dyes.The quantum dots have a number of distinguished characteristics of(ⅰ)prominent optical performance with high quantum yield,good photostability and long fluorescence lifetime,(ⅱ)simultaneous excitation of multiple quantum dots by a single light source,(ⅲ)narrow,symmetrical and size-tunable emission spectra coupled with wide absorption spectra,and(iv)broad spectral windows spanning from ultraviolet region to infrared region.We have developed single-molecule detection technique based on single-quantum dot-based fluorescence resonance energy transfer(FRET),and applied it for sensitive detection of DNA,miRNA and proteins.We also developed single-molecule detection technique capable of measuring multiple post-translational modifications and multiple DNAs in combination with liposome-quantum dot complexes,expanding its applications in clinical diagnosis and biomedical research.