Self-assembly Of Gold Nanoparticles And Their Application For SERS Detection Of Drugs

In recent years,the problem of drug abuse has aroused more and more people’s attention.China has made unremitting efforts to crack down on drug criminals.However,with the emergence of new drugs,the existing detection technology is difficult to be used in the field of detection.Surface-enhanced Raman spectroscopy has a great prospect in drug detection because of its advantages such as non-damage,high sensitivity and fingerprint recognition.In the introduction part,we mainly introduced SERS in a brief overview.Then,we reviewed the SERS substrate self-assembled materials in one,two and three dimensions.The solid and liquid substrates are classified and reported.Finally,the research progress of self-assembled precious metal nanomaterials in SERS detection field and the interaction between SERS substrate and SERS under test were introduced.This paper carried out preparation method for constructing practical SERS substrate and applied research on drug detection in Anhui CAS-SAFER Technology co.,Ltd.The specific research content is as follows:In the second chapter,gold nanorods with different aspect ratios were prepared,and their properties were characterized by using CV as the indicator molecule to determine the optimal aspect ratio of the gold nanorods required for the experiment.The climate chamber was designed and built on the basis of solvent evaporation induction effect.By adjusting the ratio of length to diameter of the gold nanorods,SERS substrate with relatively uniform texture was prepared in the climate chamber,and the conditions for inhibiting the effect of coffee ring on the substrate under the induction of gravity and other factors affecting the preparation of SERS substrate were discussed.The results showed that the prepared substrate had better stability,higher sensitivity and higher repeatability than that prepared in the conventional laboratory,meeting the requirements of actual drug detection.In the third chapter,on the basis of the second chapter,we used gold nanorods to self-assemble SERS substrate with better properties to detect drugs in urine.In view of the complex composition of urine,a rapid pretreatment method for urine was developed,and an array substrate was designed and a two-dimensional detection platform was set up for multi-sample detection.In order to verify the practical application performance of this detection method,in cooperation with anhui provincial public security department,the urine samples of several real drug addicts were tested,and the detection accuracy was 100%,which verified the practical application value of this detection method.The fourth chapter takes saliva as the test object to develop the drug test method.The collection,pretreatment and detection methods of saliva were explored.We self-assembled the gold nanometer dumbbell as SERS substrate in the climate chamber,and carried out the detection of SERS substrate for drugs in saliva,the experimental results indicated that the SERS substrate had high sensitivity and good repeatability,and it had a broad application prospect for the rapid detection of drugs in saliva.Considering that the focal length of the instrument will affect the detection performance of the treated SERS,especially the field detection,a suitable portable type SERS insert detection module was developed and the focal length was fixed.The SERS insert prepared was inserted into the tank for detection,which ensured the detection sensitivity and convenience.