| Food safety has attracted high attention and concern with the improving ofpeople’s living standards. Healthy foods, as a special kind of food, the safety of whichhas been more and more focused on. Hiding drugs and synthetic substances in healthyfoods is an adulterated behavior which becomes a common and dangerousphenomenon around the world. It is important and significant to establish effectiveand rapid methods to monitor the safety of the produets.In this thesis,methods hadbeen developed for the determination of illegal adulterants in healthy foods usingIMS、 HPLC-MS/MS and HPLC-DAD.Ion mobility spectrometer(IMS)has beendeveloped as an instrumental analytical technique for detecting and identifyingorganic compounds based upon the characteristic mobility coefficients of gas phaseions in a weak electric field which depend on the molecular weight,charge and shapeof the ions.The apparatus is fast,sensitive and robust to miniaturize for field operation,thereby providing an inexpensive and efficient tool for the analysis of variousamounts of chemical compounds.In this paper, IMS technology was used to detectillegal adulterants in dietary supplements for the preliminary screening. While theIMS methods is simple and fast,it is sometimes difficult to analyse the targetcompounds if the amount of it is traceable or the samples are complex mixtures thatinterfere with the detection signal. In this case, the sensitive UPLC-MS/MS is a goodcanditate for a comfirmative method, since it can provide strctural information of thecompound and exclude the interference of the the matrix. UPLC method is robust andreliable, it could be used in the quantification of positive samples.The developedmethods to monitor illegal adulterants in dietary supplements using IMS、UPLC-MS/MS and UPLC-DAD are simple,fast,and reliable.Therefore, it isapplicable to routine drug-adulteration screening. The main contents are included asfollows:1.To select the target compounds:The illegal drug adulterations in healthy foodsmay belong to different pharmacological categories,it’s necessary to collect thecomprhensive adulterations information. According to the function of the healthyfoods and consult the documents,79kinds of representative drugs have been chosen asthe target compounds in our study.2.An instrumental analytical approach was developed for rapid detection of20drugs(including sibutramine, Bupropion hydrochloride, glibenclamide and so on)using an ion mobility spectrometer(IMS).During the tests, the IMS was operated inthe positive mode at ambient pressure using63Ni as the ionization source and dry,clean air as drift gas which criculated in a closed loop system.Under the optimizedoperating conditions (inlet temperatrure of210℃, drift tube temperature of170℃,carrier gas flow rate of0.8L／min and drift gas flow rate of0.8L／min),the detection limit were nanogram with the analysis time of less than10s. Thismethod is simle and fast and it could be used for rapid screening and detection ofillegal adulterants in dietary supplements.3.An analytical method using ultra-high performance liquid chromatography-massspectrometry(UPLC-MS/MS) was developed for the determination of79drugs (including anorexics, stimulants, sulfonylureas and so on)in the dietary supplements.By optimizing the liquid chromatography separation and MS conditions of79kinds ofdrugs, all target compounds have a better separation and mass spectrometry response.By the use of MS for qualitative and quantitative analysis, the result has a highaccuracy, low limit and high sensitivity. It is a good canditate for a comfirmativemethod.4. An analytical method using ultra-high performance liquid chromatography(UPLC) was developed for qualitative and quantitative analysis of25illegaladulterated drugs in dietary supplements. The fast liquid chromatography systemused a gradient solvent, an HSS-T3column and a diode array detector. This systemallows dual identification based on retention time and UV spectra.It is simpe andrubust for the quantification of target compounds. |
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