Simultaneous Determination Of Fluoroquinolones In Drinki Ng Water Treatment Process

Fluoroquinolone antibiotics (FQs) is one of the most widely used antibiotics usedin human medicine, agriculture, animal husbandry and aquaculture. In recent years, theproblem ofFQs residue in water and it’s potential hazards attracted greatattention of therelevant departments and researchers, It is reported that the FQswere detected in suorcewater and tap water, hence, it is ofgreatsignificance to establish an efficient and accuratemethods to detect the FQs’s content in source water and the water treatment process, andto study the FQs abatement law in water treatment processto guaranteethe safety ofdrinking water. Five FQs—pipemidic acid (PIP), norfloxacin (NOR), ciprofloxacin(CIP), enrofloxacin (ENR) and ofloxacin (OFL) werechoosedas targetedcontaminant.All the samples formsource waterand water treatment process wereenrichedby solid phase extraction (SPE), and were detected by high performance liquidchromatography (HPLC) and quadrupole connect flight timemass spectrometry(LC-MS/MS (Q-TOF)). Finally an efficientdetection methods was constructed tosimultaneous detect residue levels of five kinds of FQs in drinking water treatmentprocess, and then the removal efficiency of the water treatment process wassystematically evaluated.The sampleswaspretreatedby SPE.Frist the extract volume, the column flow rate ofeluent, eluent and elution volume of extraction were gradually optimized to achieve thehigh demand ofhigh efficiency and purification effect. In this study, a preliminarydetection method of five FQs wereconductedwith HPLC,the method satisfytheconditionof beautiful peak shapes,clearseparation, fast and accurate liquid testing.TheLC-MS/MS (Q-TOF)conditionswas optimized and eventually establishedbased on theHPLC detect conditions. Five substances can simultaneously detected and accuratequantitative determinationwith the methodwhich realize the accurate quantification ofthe trace amounts ofFQs.A solid phase extraction (SPE)-liquid chromatography-mass spectrometry(LC-MS/MS (Q-TOF)) of the sample handling and detection methodwas established.The recoveries ofFQs in Songhua River samplesspikedwithFQs standard solution(100ng/L)arebetween81%and108%, and the relative standard deviation (RSD, n=3)arebetween1.9%and6.7%; the recoveries of FQs in deionized waterspikedwithFQsstandard solution(50ng/L)are between77%and112%, andrelative standard deviation(RSD, n=3) are between2.1%and7.1%. The limit of detectionto five FQs arebetween2and5ng/L,and the linear relationare range from2to500ng/Lwitha linear correlationcoefficient which are between0.98and0.99. Samplesform four waters,Yangtze River, Taihu Lake, the reservoir of Dasi and theSonghua River namely, and dringking water treatment process of Nanjing BHK, WuxiZQ and Liyang QX were selected, and the residual quantity of the five kinds ofFQswere detected. The results showed that the content of FQs in the Yangtze River werebetween49~205ng/Land that inthe Taihu Lake were between45~190ng/L, and that intheSonghua River were between50~185ng/L. FQs residues in water treatment processwater showed that the removal efficiency of conventional water treatment processes onFQs were between20%to40%,while treated by ozone-activated carbon treatment, fiveFQs are below the limit of quantification, which indicating that low concentrationofFQscan be effectively removedby ozone-activated carbon process.