Biomolecular Detection Method Based On Surface Plasmon Resonance Effect Of Gold Nanorods

As the development of life science,the fast decetion of biomolecules become more and more important.However,most of the methods used to detect biomolecules such as DNA,for example spectrophotometry,fluorescent dye method,PCR method and enzyme-linked immunosorbent assay,have different difficulties in the detection process like inaccurate quantification,high cost or toxic,etc.The special properties of gold nanorods(AuNRs)such as strong absorption,strong scattering and surface plasmon resonance(SPR)effect have attracted wide attention in the fields of life science,catalysis and sensors.The anisotropy of the size and shape of AuNRs makes the SPR absorption band of AuNRs exhibits transverse SPR absorption peak and longitudinal SPR absorption peak,and the adjustability of longitudinal SPR absorption peak makes it suitable as a good substrate for surface enhanced Raman scattering(SERS)and can be applied in the rapid detection of DNA molecules and protein molecules.The main content of this thesis is to explore its application in biomolecule detection around the SPR effect of AuNRs.The details are showen as follows:First,AuNRs were synthesized by seed-growth method and characterized by TEM and ultraviolet-visible spectrophotometer(UV-Vis).The methods for the silica modification and thiol-DNA modification of AuNRs were studied,which laid a foundation for the better application of AuNRs in biomolecule detection.Second,a method for multiplexed rapid detection of DNA based on hyperspectral technology and AuNRs was developed.The method uses a magnetic bead(MB)as a capture mechanism and a AuNR as a single-molecule labeled probe,utilizes the screening and separation functions of the MB to realize the proportional relationship substitution between the target DNA molecule and the AuNR,and combines with the hyperspectral unmixing algorithm to decode the mixed AuNRs label,which enabling to realize multiplexed rapid detection of DNA molecules.Third,the Raman spectroscopy encoding method based on micro-quartz pieces(MQPs)was studied,and the Raman spectroscopy encoded MQP were applied to the high throughput detectiont of protein molecules.In our experiment,four kinds of thiol Raman reporter molecules were selected and coupled with AuNRs,and then assembled onto the surface of 100*100 ?m MQPs to obtain Raman spectral encoded.MQPs.The Raman spectral signal is stable,and crosstalk between the fluorescent labeled signal and Raman coding signal does not occur and has high accuracy and good detection sensitivity.This encoded MQPs were used for the specific detection of protein molecules,which proved that this encoding method can be applied in biomolecule high-throughtput detection.