Comparative Study Of Three SERS Active Substrates Based On AgNPs

Surface-Enhanced Raman Spectra technology is an emerging analytical technology. In recent years, with the advantages of high sensitivity, short detection time and small amount of samples, this technology has been widely used in biomedical, pharmaceutical, chemical and other fields, at the same time, the preparation of SERS substrate also has become the research hotspots in this area. This paper not only introduces the theoretical knowledge related to Raman spectra, but also focuses on three SERS substrates based on AgNPs. The main contents are as follows:Firstly, this paper summarizes Raman spectra from these aspects:the basic principle of the Raman scattering, the basic characteristics of Raman spectroscopy and applications and prospects of Raman spectroscopy in biomedicine and pharmacology.Secondly, this paper has further discussion of surface-enhanced Raman spectroscopy, and introduces the discovery and development of surface-enhanced Raman spectroscopy, focusing on the two SERS enhancement mechanism:mechanism based on electromagnetic and mechanism based on chemical.Finally, three SERS active substrates based on AgNPs:capillary-AgNPs,TiO2-AgNPs and filter paper-AgNPs, were used to compare their activities. The optimized preparation condition of above three SERS active substrates are discussed, and their enhanced effects have been compared using R6G as probes. Using three optimized enhanced substrates, the SERS spectra of serum from the same healthy person were detected and analyzed. Preliminary results:these three substrates based on AgNPs are reliable and practical, and the sensitivity of TiO2-AgNPs is the best, but the prepared process is more complex; the sensitivity of filter paper-AgNPs is the next; also, the substrates prepared process of capillary-AgNPs and filter paper-AgNPs are easier than that of TiO2-AgNPs. Therefore, from the practical point of view, the filter paper-AgNPs substrates are suitable to the detection and analysis of serum.