Preparation Of Core–Shell Silver-Molecularly Imprinted Microspheres And Application In Surface-enhanced Raman Scattering

Molecular Imprinting Technology (MIT) is a new interdisciplinary subjectd. It is atechnology which makes a given analyte possess a pre-selection capability and the ability toidentify artificial receptor. Molecularly imprinted polymers (MIPs) prepared by MIT canspecifically identify the target molecules. It is better than the natural biological molecularrecognition system as for the practical value. Due to its high stability, long life time and otheradvantages, molecular imprinting technology is of great importance in the separationclinicaldrug analysis, the biomimetic catalytic, biological sensors, and many other areas ofapplication.Surface-enhanced Raman scattering (SERS) is an ultra-sensitive, nondestructivedetection technology. Because of SERS technique has a high sensitivity, relax detectioncondition and timely response, it has been widely used in chemical and biologicalsensor,single-molecule detection, surface adsorption and catalytic reaction, trace analysis,biomedical detection and other fields.The field of application of Surface-enhanced Ramanscattering (SERS) technology is widespread from the rise to the present. But lack ofpertinence and other substances (impurities) will interfere with SERS signal of the analyte,which limited the development of SERS technology. In this study, we combine the MIT withSERS technology, which possess the advantages of both parts, prepare imprinted materialswith highly selective recognition and strong binding force, develop detection of trace amountsof molecules and high selectivity of detection and provides new ways of detection for materialanalysis.Ag often serves as SERS substrate. We used Ag microspheres as a carrier and graftedmolecular imprinted polymer membrane on its surface with imprinting technique. We finallyobtained the core-shell silver-MIP microspheres (Ag-MIP). The structure and properties ofthe Ag-MIP is detected through a variety of analytical instruments, and surface-enhancedRaman scattering effect is studied.The micron-sized silver particles with rough surfaces were prepared by the ascorbic acidand citric acid reduction method. The micron grade silver ball can be controlled by orthogonal test. SERS test proved the limit of detection for mercaptopropionic acid is10-11mol/L.Micron silver ball serves as core, and we prepared core-shell silver-molecularlyimprinted polymers. Silver coated molecularly imprinted polymer outer layer isapproximately40nm thick, the cavities can selectively adsorb template molecule exist in amolecularly imprinted film, in the surface-enhanced Raman scattering (SERS) the limit ofdetection of prepared silver-molecular imprinted polymers is10-15mol/L.