| Surface-enhanced Raman spectroscopy（SERS）technology can detect low concentration chemical substances with ultra-high sensitivity.In addition,Raman detection has strong anti-interference,indicating that SERS technology is suitable for applications in various environments.Compared with fluorescence,SERS is resistant to photobleaching and photodegradation,which is suitable for long-term monitoring,and the peak bandwidth is usually very narrow,so it has obvious advantages in multiple detection.Compared with direct detection,the indirect detection method with optical nanometer tags has a wider range of application scenarios and is not affected by the Raman properties of the molecules under test.However,the design of optical nanoprobe needs to take various requirements into account and adapt to the detection system.In addition,most of the Raman nanoprobes are easy to overlap and lack of high reproducibility,how to design an efficient SERS nanoprobe with little background and high reproducibility has become the focus of many researchers.In this paper,two kinds of Prussian blue analogues coated Au nanoparticles with different Raman characteristic peaks were synthesized by self-assembly,and the controllable preparation of triple-bond SERS nano-probes was realized.The application of both nano-materials in the subtype differentiation of tumor cells and the new printing anti-counterfeiting technology was realized by using a Raman spectrometer.This paper is divided into three chapters:In the first chapter,a brief introduction of surface-enhanced Raman spectroscopy was introduced,from the historical development to the SERS enhancement principles（chemical enhancement and physical enhancement）and the elaboration of hot spots.Then the SERS active substrate was introduced in detail,including the preparation and characteristics of the metal nanoparticles and nanostructures rich in tips and gaps.Then the Raman report molecules were discussed,focusing on the Raman molecules with triple bond structure.Finally,the application progress of SERS nanometer tags was reviewed from the aspects of biosystem analysis and new printing anti-counterfeiting.In the second chapter,two kinds of gold nanoparticles coated with Prussian blue analogs（Au@PBA）were synthesized by ion doping.By adjusting the experimental parameters to optimize the synthesis process,the controllable adjustment of nanoparticles was realized.The preparation method of the substrate has simple synthesis,high reproducibility and uniformity.In addition,the Raman bio-silent zone from 1800 cm-1 to2800 cm-1 showed a characteristic and unique signal peak.The nanomaterial was modified by aptamer to synthesize a biological probe that could specifically bind surface membrane proteins of cancer cells.The differentiation of breast cancer cell subtypes was realized by calculating the SERS intensity ratio of the bio-silent zone of two kinds of nano tags,which proved the application prospect of this nanotag in the identification of cell subtypes.In the third chapter,a new type of nano-material ink suitable for printing was prepared by using the optimized Au@PBA nanoparticles,and parameters such as viscosity,surface tension and volatilizing rate were optimized to make the final mixing solvent,which was then used for printing anti-counterfeiting inkjet.The digital group and QR code group containing different information were respectively overlapped for combined printing,and a uniform color mixed pattern was obtained on the paper.Then SERS was used to point-by-point detection,and the corresponding Raman signal of each block was obtained.After separation and classification,the second-order numbers or QR codes corresponding to each Raman peak were obtained,which means the original information was acquired by Raman technology.This method realized the encryption and reading of the dual information,and it was difficult to be cracked or copied by other means,which provided a new idea for the realization of new printing and anti-counterfeiting technology. |
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