Research On Sample Pretreatments Of Sulfonamides In Water By High Performance Liquid Chromatography Tandem Mass Spectrometry

Sulfonamides is a kind of drugs which are widely used in the actual production and human life.It could have effects on various kinds of bacteria and its price is very cheap.Hence it plays an important role in keeping human and animals healthy.However,due to people's improper use for a long period,it has also caused different degrees of environmental pollution in many areas.Therefore,it is necessary to establish an efficient and easy way to monitor its contents in the environment.Magnetic solid phase extraction(MSPE)is a promising pretreatment,owing the advantages such as simple processes,little organic solvent cost and short enrichment time.Solid phase extraction(SPE)is a traditional extraction method which is easy to operate and the technology is mature.SPE has been promoted in many areas.Automatic equipments have been established as well.The main importance of the paper are:In the first chapter,the pretreatments and their applications which are widely used nowadays have been introduced.The key points are the theories and steps of magnetic solid phase extraction and solid phase extraction.Besides,the application circumstances and developing trends of future in environment and food fields have been described.A method for determination of the 4 sulfonamides(sulfapyridine,sulfamethoxazole,sulfamerazine,sulfamethazine)based on magnetic soild phase extraction and HPLC-MS/MS has been developed in the second chapter.The optimum conditions were:50 mg of magnetic material was put into 100 mL water.The pH was adjusted to 4.The conical flask was shaken for 20 min under stable frequency.Then the magnetic field was created by magnet to separate the extraction material and 4 mL of methanol solution containing 1% ammonia was used to elute.Later,all eluent was collected and blew with nitrogen until dry.Finally,it was restored with initial mobile phase of liquid chromatography and completed the HPLC-MS/MS test.The four kinds of sulfonamides analyzed had nice linearity ranging from 5~500 ?g/L.The correlation coefficients were all greater than 0.999 and the detection limit ranged from 4.2 to 4.7 ?g/L.The recoveries of the actual water samples were 72.3%~88.5%,the relative standard deviations were less than 10.2%.Magnetic solid phase extraction technology is simple and feasible coupled with high precision.It is meaningful and widely used,especially in the determination of trace contaminants.In the third chapter,the method for analysis of four kinds of antibiotics(sulfapyridine,sulfamethoxazole,sulfamerazine,sulfamethazine)by solid phase extraction combined with HPLC-MS/MS in water has been introduced.The best extraction conditions were as follows: The InertSep HLB column was activated with 3 mL of methanol and 3 mL of water.The filtered 200 mL actual water sample was pumped into the column by lines under stable flow rate(3 mL/min).The rinsing solvent was 10 mL of ultrapure water(containing5% methanol,volume ratio).After rinsing,the vacuum pump was used again to dry the column.The elution solvent was determined to be 6 m L of methanol(containing 1%ammonia,volume ratio).Then the eluent was blew out by nitrogen.After this step,it was restored by initial mobile phase of liquid chromatography and filtered by 0.22 ?m organic filtration membrane for final analysis.The method has the advantages of simple procedures,high recovery efficiency and excellent precision.Besides,it can be utilized in the analysis of large volume sample,which is practical in application.The fourth chapter summarizes the full article and gives the conclusions.