| Organotin compounds (OTCs) is a kind of important process ing products of tin, ind widely used in agriculture and industry, chemical industry, transportation, and (?)ealth and other fields, which has caused more and more serious pollution problem. OTCs can enrich in the human body through the food chain, and cause damage on the cellular immune system, central nervous system, lymphatic system, etc, which can lead to the intoxication and even death. Therefore, establishing the simple, rapid ind sensitive methods for analyzing the samples from industrial, agricultural and food, is very significance for monitoring the OTCs. The studies on the OTCs are mainly focus on the industrial products and environmental samples, but the esearches on the OTCs in food is relatively limited. Based on the analytical (?)rocedures on the OTCs at home and abroad, with the application of liquid-liquid extraction, frozen liquid-liquid extraction and low-temperature high-pressure extraction, followed by the detection with gas chromatographic-mass spectrometry, aalytical methods for simultaneously determination varieties of OTCs in different food were developed in this study, which have obtained good results. The main (?)esults of the work are as follows:1. A simple, reliable, and effective analytical method was developed for the simultaneous determination of five organotin compounds (OTCs) including monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), tetrabutyltin (TeBT) and triphenyltin (TPhT) in white wines. The OTCs were derivatized with sodium tetraethylborate (NaBEt4), and their derivatives were extracted by liquid-liquid extraction (LLE) into n-hexane. The experimental variables, such as type and volume of extraction solvents, amount of derivatization reagent NaBEt4and extraction time were optimized. The determination of ethylated derivatives of OTCs in the final extracts was carried out by gas chromatography-mass spectrometry (GC-MS). Under optimized conditions, good linearity was observed when analytical concentrations were in the range of0.01-4.0μg·mL-1, the linearity correlation coefficients were between0.9968and0.9987, with the LODs in the range of0.2-3.0μg·L-1, and the LOQs varied from0.6to10.0μg·L-1. The obtained recoveries were in the range of78.0%-120.0%, with the relative standard deviations equal to or lower than8.1%. This method was applied to the determination of OTCs in white wines with satisfactory results.2. By applying frozen liquid-liquid extraction to remove the oil ingredient of samples, a method for the simultaneous determination and quantification of4OTCs in plant oil samples by gas chromatography-mass spectrometry (GC-MS) determination has been established for the first time. The derivatization with NaBEt4and extraction for the extracts was carried out, followed by the further purification with dispersive-solid phase extraction (d-SPE), which eliminated the matrix interference and was benefit for the sample determination. The relevant experiment variables influencing the whole results including type of organic solvent for frozen extraction, amount of derivatization reagent NaBEt4, pH of buffer, type and volume of organic solvent for extraction, extraction time, type and quantity of sorbent were optimized. Under the optimized conditions, good accuracy and precision were attained. The average recoveries obtained for analytes were in the range of75.6%-114.9%. with the relative standard deviation (RSD) lower than12.6%, and the limits of detection for each OTC were ranged between0.25μg·kg-1and0.30μg·kg-1. Some different plant oil samples were detected using this developed method to demonstrate its feasibility for the OTCs determination in oil samples.3. A method for the determination of organotin compounds in water samples based on a new low-temperature high-pressure extraction device and gas chromato graphic-mass spectrometry (GC-MS) separation was developed and optimized. After extracting, three organotin species, namely dibutyltin (DBT), tributyltin (TBT), and triphenyltin (TPhT), were derivatized by sodium tetraethylborate (NaBEt4) to form ethylated less polar derivatives. The critical parameters which have a significant effect on the yield of the successive low-temperature high-pressure extraction procedure were examined, including the way of pretreatment, type of extraction solvent and the ration of water sample between extraction solvent. The developed analytical procedure was sensitive with good linearity, the detection limits of3OTCs were0.3,0.4and0.2μg·L-1, respectively. Under the optimized method, the obtained recoveries of the analytes ranged from74.1%to100.5%, and the precision between4.7%and9.1%. Due to its simplicity and reliability, it is appropriate to be used in routine laboratories for monitoring of OTC in water samples. |
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