Study On The Speciation Analysis Of Organotin In Seafood And Water Samples By ICP-MS And Its Hyphenated Techniques

In recent years, organotin compounds have been widely used as anti-bacterial and anti-fungal agents in pesticides and anti-fouling agents and plastic stabilizers, resulting in serious environmental pollution and human health’s hurt by the food chain transmission. The biological toxicity of different structure organotin is of great difference, therefore development of the speciation analysis of organotin is very important to evaluate the organotin pollution and the toxicity to the human body. At present, most research of the speciation analysis of organotin are concentrated on DBT、TBT, the reports on phenyltin are relatively few. Base on the extensive literatures, using modern separation techniques, the determination of total tin and total organotin in seafood samples, DPhT, TPhT and TePhT in seafood and water samples have been proposed with satisfactory results. The main results are summarized as follows:1. A sensitive and accurate method for the determination of total tin in seafood has been developed. After the microwave digestion, the samples were directly analysed by ICP-MS,103Rh was used as on-line internal standard to correct the matrix interference and the instrument drift. The detection limit was4.8μg/kg, the average recoveries were between85.0%-106%with the RSD between1.89%-6.10%. The proposed method has been applied to the determination of total tin in octopus, cuttle, hairtail, sea cucumber, kelp and laver with satisfactory results.2. A method for the determination of total organotin in seafood by MAE-ICP-MS has been developed. The total organotin in seafood samples were extracted with acetone-hexane (3:1, V/V) by microwave-assisted extraction technique, then analyzed by ICP-MS. Microwave extraction conditions such as volume and proportion of extraction solvent, extraction temperature and extraction time were optimized by an orthogonal array experimental design. The detection limit was0.47μg/kg and the average recoveries were between92.5%-105%with RSD between1.18%-2.38%. The proposed procedure was successfully applied to the determination of total organotin in several seafood purchased from supermarket.3. A sensitive and accurate method for the simultaneous determination of three phenyl-tin compounds(diphenyltin(DPhT), triphenyltin(TPhT) and tetraphenyltin (TePhT)) in water samples by HPLC-ICP-MS has been proposed. The sample was treated by liquid-liquid extraction with n-hexane(containing0.01%(w/v) tropolone), the organic phase was evaporated to dryness and diluted with methanol, then separated and detected by HPLC-ICP-MS. VARIAN Pursuit5μ-C18was selected as separate column, mobile phase of the HPLC was CH3OH:CH3COOH(10%)=85:15(v/v), the aqueous phase was adjusted to pH=3.0with triethylamine, flow rate was1.0mL/min, split ratio was1:1. The three compounds behaved linearly in the0.5μg/L-40μg/L concentration range with the coefficients all over0.999. The limits of instrument detection for DPhT, TPhT and TePhT were0.16μg/L,0.11μg/L and0.18μg/L respectively. The average recoveries were in the range of85.3%-109%with the RSD ranged from1.36%-7.28%. The method has been applied to the simultaneous determination of DPhT, TPhT and TePhT in Poyang lake samples with satisfactory results.4. A sensitive and accurate method for the simultaneous determination of three phenyl-tin compounds (diphenyltin, triphenyltin and tetraphenyltin) in seafood samples by MAE-HPLC-ICP-MS has been proposed. The seafood samples were extracted with acetone-hexane(3:1) by MAE, the extraction was cleaned up by solid phase extraction (C18) and was evaporated to dryness, the residue was dissolved with10mL of methanol, then detected by HPLC-ICP-MS. VARIAN Pursuit5μ-C18was selected as separate column. The three compounds behaved linearly in the0.50μg/L-40.0μg/L concentration range with the coefficients all over0.999. The limits of instrument detection for DPhT, TPhT and TePhT were0.16μg/L,0.11μg/L and0.18μg/L respectively. The average recoveries were in the range of91.2%-104%with the RSD ranged from0.94%-3.30%. The proposed procedure was successfully applied to the determination of three phenyl-tin compounds in several seafood purchased from supermarket with satisfactory results.