在线柱浓缩-超高效液相色谱法测定水体中的痕量甲萘威和呋喃丹

摘要

An online column enrichment-ultra high performance liquid chromatography ( UH-PLC ) method was developed to determine trace carbaryl and carbofuran in water. The sample was injected into a UHPLC system directly after filtration with 0.22 μm membrane, and then enriched by online solid phase extraction ( SPE ) column. The analyte was back-flushed into the analytical column Acclaim RSLC C18 ( 100 mm ×2. 1 mm, 2. 2 μm ) by valve switching method. The mobile phases were 10 mmol/L ammonium acetate buffer ( pH 5.0, adjusted by acetic acid ) and acetonitrile in a gradient elution mode with a flow rate of 0. 8 mL/min, and detected by a diode array detector with the detection wavelength of 280 nm. The good linear ranges of carbaryl and carbofuran were 1.0- 100 μg/L with the correlation coefficients ( r2 ) larger than 0. 999 9, and the limits of detection ( S/N = 3 ) were 0. 5 μg/L and 0. 25 μg/L, respectively. The average spiked recoveries were in the range of 76. 0% - 120. 0%. The method has been applied to determine trace carbaryl and carbofuran in water samples with satisfactory results.%采用在线柱浓缩-超高效液相色谱联用技术测定水体中痕量甲萘威和呋喃丹.水样过滤后直接进样,采用固相萃取小柱富集待测物,梯度洗脱后,利用阀切换技术将待测物反冲至分析柱Acclaim RSLC C18(100 mm×2.1 mm,2.2 μm)上进行色谱分离,以10 mmol/L 醋酸铵缓冲溶液(pH 5.0,用醋酸调节)和乙腈分别为流动相A和B,梯度洗脱,泵流速为0.8 mL/min,检测波长为280 nm,二极管阵列检测器检测.甲萘威和呋喃丹在1.0～100 μg/L 范围内线性良好(相关系数r2 ＞ 0.9999),检出限(S/N=3)分别为0.5和0.25 μg/L,加标回收率为76.0% ～120.0%.用所建立的方法测定了水中痕量的甲萘威与呋喃丹的含量,结果令人满意.