A method based on cloud point extraction was developed to determine phthalate esters including di-ethyl-phthalate （DEP）, di- （2-ethylhexyl）-phthalate （DEHP） and di-cyclohexyl-phthalate （DCP） in environmental w...A method based on cloud point extraction was developed to determine phthalate esters including di-ethyl-phthalate （DEP）, di- （2-ethylhexyl）-phthalate （DEHP） and di-cyclohexyl-phthalate （DCP） in environmental water samples using high-performance liquid chromatography separation and ultraviolet detection （HPLC-UV）. The non-ionic surfactant Triton X-114 was chosen as extraction solvent. The parameters affecting extraction efficiency, such as concentrations of Triton X-114 and Na2SO4, equilibration temperature, equilibration time and centrifugation time were evaluated and optimized. Under the optimum conditions, the method can achieve preconcentration factors of 35, 88, 111 and detection of limits of 2.0, 3.8, 1.0 ng/ml for DEP, DEHP and DCP in 10-ml water sample, respectively. The proposed method was successfully applied to the determination of trace amount of phathalate esters in effluent water of the wastewater treatment plant and the lixivium of plastic fragments.展开更多
采用HPLC结合紫外光谱法,同时测定四种竹叶黄酮碳苷(荭草苷、异荭草苷、牡荆苷和异牡荆苷)。采用Waters XTerra MS C18色谱柱(250mm×4.6mm,5μm),流动相为乙腈和0.5%甲酸水溶液,等梯度洗脱,流速1mL·min-1,柱温30℃,检测波长36...采用HPLC结合紫外光谱法,同时测定四种竹叶黄酮碳苷(荭草苷、异荭草苷、牡荆苷和异牡荆苷)。采用Waters XTerra MS C18色谱柱(250mm×4.6mm,5μm),流动相为乙腈和0.5%甲酸水溶液,等梯度洗脱,流速1mL·min-1,柱温30℃,检测波长360nm。建立各个组分在0.1~10.0mg·L-1范围内系列浓度的混合标准工作曲线,其相关系数R2均优于0.999,且在22min内得到较好分离。方法检出限介于0.03~0.07mg·L-1,定量限介于0.04~0.08mg·L-1。分别将标准品与样品中四种黄酮碳苷的紫外光谱(240~400nm)进行比对,荭草苷、异荭草苷、牡荆苷和异牡荆苷相应的光谱曲线形状以及特征吸收波长都表现出高吻合度。取竹叶样品经热回流提取,石油醚萃取及AB-8大孔树脂纯化后,再采用HPLC结合紫外光谱法检测得荭草苷、异荭草苷、牡荆苷和异牡荆苷四种黄酮碳苷相对于竹叶黄酮粉的百分含量分别为13.73,49.68,7.85和30.70mg·g-1,平均回收率为34.90%~87.64%,相对标准偏差为0.41%~10.83%。本方法实现了在较短时间内快速分析竹叶中四种黄酮碳苷,样品稳定,重现性好,为市售竹叶黄酮碳苷的质量控制提供参考。展开更多
基金Projected supported by the National Basic Research Program (973)of China (No. 2003CB415001)the Pilot Program of KnowledgeInnovation Program of Chinese Academy of Sciences (No. KZCX3-SW-431).
文摘A method based on cloud point extraction was developed to determine phthalate esters including di-ethyl-phthalate （DEP）, di- （2-ethylhexyl）-phthalate （DEHP） and di-cyclohexyl-phthalate （DCP） in environmental water samples using high-performance liquid chromatography separation and ultraviolet detection （HPLC-UV）. The non-ionic surfactant Triton X-114 was chosen as extraction solvent. The parameters affecting extraction efficiency, such as concentrations of Triton X-114 and Na2SO4, equilibration temperature, equilibration time and centrifugation time were evaluated and optimized. Under the optimum conditions, the method can achieve preconcentration factors of 35, 88, 111 and detection of limits of 2.0, 3.8, 1.0 ng/ml for DEP, DEHP and DCP in 10-ml water sample, respectively. The proposed method was successfully applied to the determination of trace amount of phathalate esters in effluent water of the wastewater treatment plant and the lixivium of plastic fragments.
文摘采用HPLC结合紫外光谱法,同时测定四种竹叶黄酮碳苷(荭草苷、异荭草苷、牡荆苷和异牡荆苷)。采用Waters XTerra MS C18色谱柱(250mm×4.6mm,5μm),流动相为乙腈和0.5%甲酸水溶液,等梯度洗脱,流速1mL·min-1,柱温30℃,检测波长360nm。建立各个组分在0.1~10.0mg·L-1范围内系列浓度的混合标准工作曲线,其相关系数R2均优于0.999,且在22min内得到较好分离。方法检出限介于0.03~0.07mg·L-1,定量限介于0.04~0.08mg·L-1。分别将标准品与样品中四种黄酮碳苷的紫外光谱(240~400nm)进行比对,荭草苷、异荭草苷、牡荆苷和异牡荆苷相应的光谱曲线形状以及特征吸收波长都表现出高吻合度。取竹叶样品经热回流提取,石油醚萃取及AB-8大孔树脂纯化后,再采用HPLC结合紫外光谱法检测得荭草苷、异荭草苷、牡荆苷和异牡荆苷四种黄酮碳苷相对于竹叶黄酮粉的百分含量分别为13.73,49.68,7.85和30.70mg·g-1,平均回收率为34.90%~87.64%,相对标准偏差为0.41%~10.83%。本方法实现了在较短时间内快速分析竹叶中四种黄酮碳苷,样品稳定,重现性好,为市售竹叶黄酮碳苷的质量控制提供参考。
