Determination Of Acrylamide In Food And Environmental Samples By Capillary Electrophoresis

Capillary electrophoresis(CE),due to its advantages of high efficiency,fast separation,cost-effective,relatively low detection limit and so forth,is widely applied to the fields of environment,medicine,biology,chemical industry,etc.Acrylamide is a small molecular compound with polarity,which is a potential threat to human health because of its neurotoxicity,genotoxicity and carcinogenicity.Acrylamide is often produced in the process of food heating.However,the current research mainly focuses on flour productsand the rice products are less studied.Moreover,flocculants containing acrylamide are often used in the process of the sewage treatment.Therefore,this study mainly focuses on the acrylamide in sewage sludge,water samples and rice products.A method for the extraction and determination of acrylamide in rice products,waste water and residual sludge by matrix solid phase extraction-capillary electrophoresis was established,which has successfully been applied to the determination of real samples.Furthermore,off-line derivation acrylamide method coupled to capillary electrophoresis is also used to determine the acrylamide in rice products and water samples.The main works completed are as follows:The fundamental properties,mechanism and detection methods of acrylamide are emphasized in chapter 1.And the advantages and disadvantages of the existing methods are compared.Also,the basic principle,composition,separation mode and characteristics of capillary electrophoresis are introduced.In chapter 2,a matrix dispersive solid phase(MSPD)extraction-capillary electrophoresis method was established for the assay of acrylamide in rice products and sludge.The chromatographic conditions,the selection of dispersant and elution,their dosage and other parameters were optimized.The optimal sample pretreatment and separation conditions are C18 and Florisil mixture(1:4 m/m)as adsorbent,the sample and the sorbent mass ratio was 5:9,eluent composed of acetone:dichloromethane(6:4 V/V)and 10 m L elution volume was.The running buffer was boric solution(20mmol·L-1,p H=8.4)and the separation voltage was 15 k V.The linear ranges of acrylamide were 10 ~ 200 ?g·m L-1(r=0.9998).The detection limit(?g · m L-1)was 0.62(S/N=3).The recovery coefficiencies of acrylamide in the samples were in the range of 77.2%~104.2%.The acrylamide content in sludge,snow-biscuit,guoba,milaotouand xiaoxiaosu were 1.02 mg/kg,8.39 mg/kg,27.3mg/kg,31.9 mg/kg,29.7 mg/kg respectively.The relavant RSD ranged from 1.36% to6.41%.The results showed that the method is simple,accurate and reliable,and can be used for the detection of acrylamide in rice products.A method of off-line derivatization capillary electrophoresis was used to determine the acrylamide in rice products and water samples.The optimum conditions for the derivatization of acrylamide were investigated.Water was used for ultrasonic extraction.3-mercaptobenzoic acid was used as derivative agent and borate as catalyst.The sample was heated in water bath at 45? for 5 hours and ethyl acetate was acted as extractant.The running buffer was borate solution(25mmol·L-1,p H=8.97)and the separation voltage was 15 k V.The linear ranges of acrylamide were 10 ~ 200?g · m L-1(r = 0.9986)and the detection limit was 0.21 m g/m L(S/N=3)under optimized conditions.The acrylamide content in samples of water sample,snow-biscuit,guoba,mitaotou,xiaoxiaosu were 0,7.14 mg/kg,24.7 mg/kg,28.3mg/kg,28.9mg/kg respectively.This method has the advantages of mild reaction conditions and the peak area was 5 times higher than the original one under the same concentration,which proved that it can be applied to the detection of acrylamide in rice products and water samples.