The Research On Pretreatment And Determination Methods Of Chlorophenols And Isothiazolinones In Environment

Abstract: With the development of economics and technology, the production of different kinds of chemicals is increasing year by year. Generally, most of chemicals are composed of organic compounds. In a way, these organic compounds can be bioaccumulated and are toxic to organisms, which can pose a serious threat to environment and human health. Consequently, some rapid and sensitive analysis methods are supposed to be established to monitor these organic compounds in environment effectively. However, environment samples not only exist in diverse forms, but also consist of complicated material, which make the simultaneous analysis of different organic pollutants in environment more difficult. In order to meet the need of analysis, the analysis methods include not only the rapid and effective pretreatment methods, but also the sensitive and specified determination methods.This paper selected chlorophenols and isothiazolinones as target analytes. With the optimization of sample pretreatment, chromatography condition and mass spectrometry condition, two analysis methods were established: 1, An ultra high performance liquid chromatography-quadrupole time of flight-tandem mass spectrometry screening method with solid phase extraction was developed for the determination of four chlorophenols in sediments. 2, An ultra high performance liquid chromatography-triple quadrupole-tandem mass spectrometry method with solid phase extraction was developed for the determination of three isothiazolinones in water, and the quadrupole time of flight-tandem mass spectrometry method was also established for the auxiliary confirmation of target compounds.The main work of this paper is depicited as follows:1. An ultra high performance liquid chromatography-quadrupole time of flight-tandem mass spectrometry method with solid phase extraction was developed for the determination of four chlorophenols(chlorophene, dichlorophene, hexachlorophene, bromochlorophene) in sediments. Samples were extracted with 1% formic acid in acetone(V:V), purified by the strong-anion exchange column of solid phase extraction and eluted by methanol-ethyl acetate(1:1, V:V)containing 5% formic acid. The separation of four target compounds was accomplished by a Waters HSS C18 column(2.1 mm×100 mm, 1.8 ?m)in gradient elution with a mobile phase A of 0.004% formic acid in water(V:V) and a mobile phase B of methanol. The mass spectrometry employed electrospray ionization in negative mode, employed the peak area of parent ion as the basis of quantitative analysis, employed the retention time, one specified daughter ion and the relative abundance of ions as the basis of qualitative analysis. Both hexachlorophene and bromochlorophene manifested a satisfactory linearity in the range of 0.2-5 ?g?L-1, dichlorophene in the range of 0.4-20 ?g?L-1, and chlorophene in the range of 2-100 ?g?L-1(R2>0.99). The average recoveries ranged from 69.5%-99.6% at three spiked levels, with the relative standard deviation varying from 3.4%-14.8%. Applying the method metioned above, 12 sediment samples were determined, of which chlorophene was detected in three samples, dichlorophene was detected in two samples, hexachlorophene and bromochlorophene were not detected. This method was accurate and sensitive for the determination of four chlorophenols in sediments.2. An ultra high performance liquid chromatography-triple quadrupole-tandem mass spectrometry method with solid phase extraction was developed for the determination of three isothiazolinones(1,2-benzisothiazolin-3-one, 2-methyl-3(2H)-isothiazolone, 5-chloro-2-methyl-3(2H)-isothiazolone) in water, and the quadrupole time of flight-tandem mass spectrometry method was also established for the auxiliary confirmation of target compounds. Samples were purified by the hydrophilic-lipophilic balance column of solid phase extraction and eluted by methanol. The separation of three target compounds was accomplished by a Waters HSS C18 column(2.1 mm×100 mm, 1.8 ?m)in gradient elution with a mobile phase A of water and a mobile phase B of methanol. The mass spectrometry employed electrospray ionization in positive mode. In the TQ-MS/MS mode, Multiple Reaction Monitoring was employed for both the quantitative and qualitative analysis. In the QTOF-MS/MS mode, the retention time, two specified daughter ions and the relative abundance of ions were employed for the qualitative confirmation of target compounds. All analytes manifested a satisfactory linearity in the range of 0.1-20 ?g?L-1(R2>0.99) in the TQ-MS/MS mode, while in the QTOF-MS/MS mode, 1,2-benzisothiazolin-3-one and 5-chloro-2-methyl-3(2H)-isothiazolone manifested a satisfactory linearity in the range of 2-100 ?g?L-1, 2-methyl-3(2H)-isothiazolone in the range of 2-100 ?g?L-1(R2>0.99). The average recoveries of BIT and CMI ranged from 80.2%-112.0% at three spiked levels, with the relative standard deviation varying from 1.7%-7.3%. While the average recoveries of MI was lower than 30%. Applying the method metioned above, 10 water samples were determined, of which in the TQ-MS/MS mode, 2-methyl-3(2H)-isothiazolone was detected in two samples, 1,2-benzisothiazolin-3-one and 5-chloro-2-methyl-3(2H)-isothiazolone were not detected. While in the QTOF-MS/MS mode, all target compounds were not detected. This method was accurate and sensitive for the determination of three isothiazolinones in water.