Construction And Application In Sers Detection Of Core-Shell Gold Nanostars

Surface-enhanced Raman scattering spectroscopy has become one of the most important analytical techniques in the current analytical community.In recent years,the detection technology based on surface-enhanced Raman scattering has developed rapidly,and its detection sensitivity has reached the single molecule level.However,it is still a great challenge to realize double-layer signal amplification and prepare SERS nanomaterials with high sensitivity and stability.In this paper,the preparation of gold nanostars was explored.By constructing core-shell gold nanostars and embedding Raman reporter molecules into them,nanomaterials with good stability and double amplification of SERS signals were successfully prepared.We combined surfaceenhanced Raman spectroscopy with immunomagnetic beads and lateral flow immunochromatography to obtain two new methods for rapid and sensitive detection of inflammatory marker CRP.Based on the synthesis and application of core-shell structure nano Venus,This paper mainly conducts experiments and explorations in the following two directions :1.The morphology and composition of nanoparticles are the key factors to improve the sensitivity of SERS detection.However,the collection of multiple signal amplification factors cannot be achieved,which undoubtedly limits the effect of signal amplification.Therefore,we designed a core-shell structure of gold nanostar@ nanoshell by changing the morphology and composition of gold nanostar,and embedded Raman reporter molecules into the shell to prepare SERS nanomaterials with ultra-high sensitivity and stability.The effects of the number of thorns on the surface of the nanoparticles,the thickness of the gold shell,and the intensity of the SERS signal and the electromagnetic field were studied.Compared with the traditional Au NPs and Au NSs,the core-shell nanomaterials showed obvious electromagnetic field enhancement of 4 orders of magnitude,and the stability can reach up to 1 year.2.C-reactive protein(CRP)is a pro-inflammatory cytokine that can be triggered and associated with a variety of diseases and pathological conditions.It is considered as a rumor indicator of cerebrovascular disease,cancer,and myocardial infectious inflammation.Conventional SERS probes usually use the method of directly adsorbing marker molecules on the surface of nanoparticles.These labeled molecules are susceptible to interference from complex environments and samples,which may lead to their separation from the SERS substrate and release into the solution,causing poor signal repeatability and even false positive / negative results.Therefore,by using the core-shell structure gold nanostar,the Raman reporter molecule is embedded in the shell to achieve the double-layer effect of signal amplification and Raman molecule protection.We combined it with immunomagnetic beads for liquid phase determination,and used the enrichment performance of magnetic beads to once again improve the sensitivity of detection,with a detection limit as low as 0.001 ng/m L.We then combined the material with lateral flow immunochromatography for visual detection without complex instruments,with a detection limit as low as 0.01 ng/mL.