| In the modern history of China,the abuse and popularity of drugs have dramatically damaged our nation.Nowadays,the threat of drugs is not only from the traditional drugs,but also from emergering drugs.With rapid progress and development of scientific level and pharmaceutical technology,the amount and kinds of synthetic drugs has exceeded the traditional drugs,thus,there is increasing demond to develop the detect strategy for rapid detection of drugs,further inhibiting the spread of drugs and fight against drug crime.Today,the methods of drugs identification by public security and judicial departments mainly depend on the colloidal gold test paper to preliminarily screen,then GC-MS ultimately verify.However,this method is not suitbale for field test,because of slower signal responsing and labor and resources demanding as well as enormous cost.In recent years,with the advantages of unique spectroscopic fingerprint,rapid detection,less sample consumption,nondestructive examination,high sensitivity,surface-enhanced Raman spectroscopy(SERS)technique has aroused wide attention and acted as one of the most popular robust analytical tools has been widely used in various fields,such as explosives detection,medical security,archaeology,food safety and illicit drugs detection.However,in human body fluid,such as urine and blood,drugs have lower concentration,and itcontains a great deal of urea,protein,amino acid and so on,which will interfere with the drug detection.Beside,for field detection,SERS substrates are required to own advantages of high stability,reproducibility and sensitivity.In light of above problems of drug detection,the details of this thesis is as follow:First,we introduced the overview of drugs,the detecting method of drug,the history of SERS,enhancement mechanism and the research progress of technology to detect drugs by SERS.In chapter 2,we studied the detective method of cocaine,which is one of most widely abused drugs in the world.In view of the trace amount of drugs and interferences of other biological molecules from urine,we proposed a rapid and effective pretreatment method for separation and purification of cocaine in human urine samples.The purification progress,demonstrating the advantages of simple operation,fast time response,better extraction efficiency as well as the lower consumption of purification reagent is not dependent on another instrument.For acquiring SERS substrate with excellent sensitivity,uniformity,and reproducibility,quasi-spherical and uniform GNPs were synthesis firstly by use of seed growth method,then,forming orderly close-packed GNPs film functionalized with CTAB.A handheld Raman was used spectrometer to detect of cocaine in human urine and obtain good detection results.The purification and detection progress can complished within 3.5 min,which indicates greatly practical applications on field detection.In chapter 3,we established a method to detect drugs in human serum by SERS.It enlarged the scope of biological specimens for the purpose that tricky drug abusers are not reluctance to provide urine on spot detection and expanded the application of SERS.Because the serum composition is more complex than urine and interferences will exist by direct detection of other biological molecules form serum,we established a rapid pretreatment strategy for separation and purification of drug in real human serum samples and further confirmed the sensitivity of this method.In order to study the influence of individual differences,thirty samples of serum spiked with cocaine from Hefei cancer hospital of.Chinese academy of sciences were purificated and detected.In addition,this method is also suitable for the rapid purification and detection of amphetamines in serum.In chapter 4,we detected suspected addict's urine after purification process using SERS to verify the reliability and feasibility of pretreatment strategy.Experimental results showed that the rapid detection method of drugs we established has high application value. |
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