Determination Of Organic Compounds In Water Samples By HPLC Combined With Liqiud-Liqiud Microextraction Using Supramolecular Solvent

:In order to get accurate date and good reproducibillity in chemical analysis, it is necessary to make sample preparation for some matrix complex, low concentration samples. It is usually crucial to the success of the samples analysis, especially embodied in the analysis of organic compounds. Therefore, the rapid, facile automatic sample preparation technique has become one of the important research direction for analytical chemistry workers.Liquid-phase microextraction, as a sample preparation technology, was developed in recent years. It is a new environmental benign sample preparation technique which incorporates sampling, extraction and concentration into a single step and makes uses of only a small amount of solvent for concentrating analytes from aqueous samples. Recent years, supramolecular solvents have been widely used in separation and extraction process. The traditional sovent has disadvanges of strong volatile, high toxic, serious damage to the environment, etc. Using supramolecular solvents instead of organic solvent can overcome the shortcomings from the source.On the basis of previous work, this paper used supramolecular solvent instead of organic solvent combing vortex-assisted liquid-liquid microextraction technology to determine organic pollutants in samples. It’ s main content are as follows:1. A novel, efficient and environmental friendly method, supramolecular solvent liquid-liquid microextraction (SMS-LLME) combined with high-performance liquid chromatography (HPLC) was first established for the determination of p-nitrophenol and o-nitrophenol in water samples. Several important parameters influencing extraction efficiency, such as the type and volume of extraction solvent, pH of sample, temperature, salt effect, extraction time and stirring rate, were optimized in detail. Under the optimal conditions, the enrichment factor was166for p-nitrophenol and160for o-nitrophenol, and the limits of detection by HPLC were0.26and0.58μg·L-1,respectively. Excellent linearity with coefficients of correlation from0.9996to0.9997was observed in the concentration range of2-1000μg·L-1. The ranges of intra-day and inter-day precision (n=5) at100μg·L-1of nitrophenols were5.85-7.76%and10.2-11.9%, respectively. The SMS-LLME method was successfully applied for preconcentration of nitrophenols in environmental water samples.2. A novel, fast and efficient method for the analysis of nitroaniline isomers as model compounds was developed using vortex-assisted supramolecular solvent liquid-liquid microextraction (VA-SMS-LLME). A vortex mixer was used as the mixer in supramolecular solvent liquid-liquid microextraction, and it decreased the extraction time greatly. Several important parameters influencing extraction efficiency, such as the type and volume of extraction solvent, pH of sample, salt effect and extraction time, were optimized in detail. Under the optimal conditions, the enrichment factor was133for p-nitroaniline,98for m-nitroaniline and115for o-nitroaniline, and the limits of detection by HPLC were0.3,1.0and0.5μg·L-1, respectively. Linearity with determination coefficient from0.9981to0.9993was evaluated using water samples spiked with the nitroanilines at fourteen different concentration ranging from4to1000μg·L-1. The ranges of intra-day and inter-day precision (n=5) at10μg·L-1of nitroanilines were1.67-7.05%and9.4-11.6%, respectively. The VA-SMS-LLME method was successfully applied for preconcentration of nitroanilines in environmental water samples.3. A novel, fast and efficient method for the analysis of TBHQ and BHA as model compounds was developed using vortex-assisted supramolecular solvent liquid-liquid microextraction (VA-SMS-LLME). A vortex mixer was used as the mixer in supramolecular solvent liquid-liquid microextraction, and it decreased the extraction time greatly. Several important parameters influencing extraction efficiency, such as the type and volume of extraction solvent, pH of sample, salt effect and extraction time, were optimized in detail. Under the optimal conditions, the enrichment factor was128to136, and the limits of detection by HPLC were1.1and1.6μg·L-1, respectively. Linearity with determination coefficient from0.9986to0.9989was evaluated using water samples spiked with the TBHQ and BHA at eleven different concentration ranging from10to1000μg·L-1. The ranges of intra-day precision (n=5) at10μg·L-1of TBHQ and BHA was4.50-6.33. The VA-SMS-LLME method was successfully applied for preconcentration of TBHQ and BHA in fruit juice. There were19graphs,12tables and133references in this paper.