Ionic Liquid-dispersed Liquid-liquid Microextraction For Rapid Enrichment And Detection Of Alkylphenol Compounds In Detergents

Objective:This subject uses ionic liquid-dispersed liquid-liquid micro-extraction pretreatment technology to construct a new method for the enrichment and purification of alkylphenol compounds in detergents,and establish a synchronous detection method with high accuracy and precision using liquid chromatography tandem mass spectrometry（HPLC-MS/MS）of nonylphenol（NP）,nonylphenol polyoxyethylene ether（NPEO）,octylphenol（OP）,octylphenol polyoxyethylene ether（OPEO）.The pretreatment method and the detection method can provide technical support for the rapid and accurate detection of alkylphenol compounds in detergents,and serve the health of consumers.Methods:1.Combine ionic liquid dispersion liquid-liquid microextraction with high performance liquid chromatography tandem mass spectrometry to establish a laboratory method for rapid detection of alkylphenols and polyoxyethylene ethers in detergents.Screen the extraction agent and its volume,dispersant and its volume,the pH value of the aqueous phase,the type and intensity of ions,auxiliary methods,extraction time and other factors that affect the extraction effect.By comparing the enrichment efficiency under different conditions,the enrichment and purification method of alkylphenol compounds in detergents based on ionic liquid-dispersed liquid-liquid micro-extraction technology is established.2.By optimizing the conditions of high performance liquid chromatography and tandem mass spectrometry,a method for the detection of alkylphenol compounds in detergents by high performance liquid chromatography tandem mass spectrometry was constructed.Evaluating methodology through correlation coefficient,limit of detection and limit of quantification,measurement precision,method repeatability and reproducibility,and standard recovery rate.3.Through random sampling,using the established pre-processing and testing methods,the actual samples of 30 detergents on the market were tested to examine the practicability of the methods.Results:1.In the process of ionic liquid dispersion liquid-liquid micro-extraction,the sample solution is added with Na₂SO₄ as the ionic strength regulator,the concentration is 1%;the pH of the sample solution is adjusted to 6;100μL of[Hmim][PF6]is used as the extractant;methanol is used as the dispersion and the volume is1000μL;after 15 minutes of ultrasonic extraction,the centrifugation time is 5minutes for the best enrichment efficiency.2.This method detects nonylphenol in detergents with a standard recovery rate of91.27%～95.69%,and the relative standard deviation（RSD）is between 1.33%～1.88%,The recovery rate of octylphenol is 90.28%～95.77%,the RSD is 1.05%～1.46%,the recovery rate of nonylphenol polyoxyethylene ether is 90.28%～94.61%,and the RSD is between 1.32%～1.38%.The recovery rate of octylphenol polyoxyethylene ether is89.13%～94.38%,and the RSD is 1.13%～1.56%.The method has simple operation,low cost,and small amount of organic reagents,and is suitable for rapid detection of alkylphenols and polyoxyethylene ethers in detergents in laboratories.3.The results of random inspection of 30 common detergents on the market are:a small amount of NP and NPEO was detected in 1 sample in a kitchen cleaning agent,the four substances NP,OP,NPEO and OPEO were detected in a sample of a washing machine cleaner and a sample of a floor cleaner.No alkylphenol and its polyoxyethylene ether were detected in the other 27 samples.Conclusions:The subject established a new method for the determination of alkylphenol compounds in detergents based on ionic liquid liquid-liquid microextraction pretreatment technology and used high performance liquid chromatography tandem mass spectrometry（HPLC-MS/MS）to detect NP,NPEO,OP and OPEO.The recovery rate of alkylphenol compounds in detergents detected by the pretreatment method and detection method is 89.13%～95.77%,and the RSD is 1.05%～1.88%.The method is simple in operation,high in sensitivity,good in reproducibility,low in detection cost,and environmentally friendly,and at the same time avoids the large amount of use of organic solvents.