對-羥基苯甲酸酯常被用來當作抗菌的防腐劑，土壤、底泥和水資源中皆有其蹤跡的存在。過往研究顯示對-羥基苯甲酸酯對於人體與水中有機物有潛在的長期影響，可能造成內分泌干擾，干擾睪酮素的分泌以及增加罹患乳癌的風險。 本研究開發出一套檢測對-羥基苯甲酸酯在海鮮中含量的方法，使用基質固相分散法 (Matrix solid-phase dispersion, MSPD) 同時將待測物進行萃取以及淨化，利用不同組合的沖提溶劑、分散劑和吸附劑，達到去除脂肪的效果。影響萃取效率的參數， 使用實驗設計以及變異數分析進行探討，最佳化的萃取條件為：將0.5 g魚肉、0.5 g無水硫酸鈉和1 g矽酸鎂置於震盪機均勻混和，將混和物轉移到含有1.5 g吸附劑 (矽膠:C18 = 9:1) 的玻璃管柱中，接下來使用12 ml的乙腈進行沖提，最後將萃取液旋濃乾燥，以50 μL甲醇回溶，取10 μL與1 μL醋酸酐進行線上衍生，導入GC/MS進行分析。 此方法回收率介於93%-112%之間；在 4-500 ng/g 的線性範圍內，檢量線具有良好線性關係 (R2>0.9994)；偵測極限小於0.3 ng/g。精密度以及準確度，相對標準偏差皆小於8 %，表示此方法具有良好的穩定性以及精密度。 ;ABSTRACT Parabens or esters of p-hydroxybenzoic acid are used as antimicrobial preservatives. Parabens are commonly detected in aquatic systems, including environmental water, sediment and sludge. Previous studies have reported that parabens have potential long-term effects on aquatic organisms and human health. Parabens cause endocrine disruptive which adversely affects the secretion of testosterone and enhance the risk of breast cancer. An optimized method for determination of parabens in seafoods was presented. Analytes were simultaneously extracted and cleaned-up using the matrix solid-phase dispersion (MSPD) procedure. Several combinations of elution solvent, dispersants and clean-up co-sorbent were investigated in order to get free-lipid extracts and quantitative recoveries of parabens. The parameters affecting the MSPD extraction efficiency was investigated by statistical experimental design and analysis of variance. Under optimized condition, 0.5 gram of fish sample was mixed with 0.5 gram anhydrous sodium sulfate and dispersed with 1.0 gram of Florisil and then transferred to SPE column containing 1.5 gram of silica:C18 (9:1) as clean-up co-sorbent. Analytes were eluted with 12 mL of acetonitrile. The extract was concentrated to dryness under a gentle stream of nitrogen and re-constituted with 50 µL methanol. Then, a fraction of 10 µL was mixed with 1.0 µL acetic anhydride reagent and directly injected to GC-MS system to obtain online derivatization. The optimized method presented good linearity (R2 > 0.9994) for all target analytes over six level concentration in ranged 4-500 ng/g, provided low detection limits less than 0.3 ng/g, obtained a good precision (relative standard deviations less than 8% in inter-and intra- day analysis) and offered good recoveries (in ranged 93%-112%).
