建立超高效液相色谱-串联质谱测定全蛋粉中双酚A和双酚S的检测方法。全蛋粉经水复溶后经乙腈提取,提取液使用分散系固相萃取-基质增强脂质去除产品进行除脂,使用Oasis PRiME HLB小柱进一步净化,使用超高效液相串联质谱测定,负离子多反...建立超高效液相色谱-串联质谱测定全蛋粉中双酚A和双酚S的检测方法。全蛋粉经水复溶后经乙腈提取,提取液使用分散系固相萃取-基质增强脂质去除产品进行除脂,使用Oasis PRiME HLB小柱进一步净化,使用超高效液相串联质谱测定,负离子多反应监测(MRM)模式测定,内标法定量。结果显示:双酚A在1~50μg/kg范围内呈线性,相关系数为0.9991,加标回收率为98.8%~105.0%,日内和日间相对标准偏差分别为3.84%~8.58%和5.65%~8.74%,检出限为0.3μg/kg,定量限为1.0μg/kg;双酚S在0.4~20μg/kg范围内呈线性,相关系数为0.9995,加标回收率为98.5%~102.5%,日内和日间相对标准偏差分别为3.01%~7.86%和3.18%~7.03%,检出限为0.1μg/kg,定量限为0.3μg/kg。实际样品测定结果分别为:双酚A 2.4~3.8μg/kg;双酚S 0.48~0.82μg/kg。本方法前处理简单、高灵敏度适用于全蛋粉中双酚A和双酚S的日常测定。展开更多
Batch equilibrium experiments were conducted to investigate cadmium (Cd) sorption by two permanent-charge soils, a yellow-cinnamon soil and a yellow-brown soil, and two variable-charge soils, a red soil and a latosol,...Batch equilibrium experiments were conducted to investigate cadmium (Cd) sorption by two permanent-charge soils, a yellow-cinnamon soil and a yellow-brown soil, and two variable-charge soils, a red soil and a latosol, with addition of selected organic acids (acetate, tartrate, and citrate). Results showed that with an increase in acetate concentrations from 0 to 3.0 mmol L-1, Cd sorption percentage by the yellow-cinnamon soil, the yellow-brown soil, and the latosol decreased. The sorption percentage of Cd by the yellow-cinnamon soil and generally the yellow-brown soil (permanent-charge soils) decreased with an increase in tartrate concentration, but increased at low tartrate concentrations for the red soil and the latosol. Curves of percentage of Cd sorption for citrate were similar to those for tartrate. For the variable-charge soils with tartrate and citrate, there were obvious peaks in Cd sorption percentage. These peaks, where organic acids had maximum influence, changed with soil type, and were at a higher organic acid concentration for the variable-charge soils than for the permanent charge soils. Addition of cadmium after tartrate adsorption resulted in higher sorption increase for the variable-charge soils than permanent-charge soils. When tartrate and Cd solution were added together, sorption of Cd decreased with tartrate concentration for the yellow-brown soil, but increased at low tartrate concentrations and then decreased with tartrate concentration for the red soil and the latosol.展开更多
文摘建立超高效液相色谱-串联质谱测定全蛋粉中双酚A和双酚S的检测方法。全蛋粉经水复溶后经乙腈提取,提取液使用分散系固相萃取-基质增强脂质去除产品进行除脂,使用Oasis PRiME HLB小柱进一步净化,使用超高效液相串联质谱测定,负离子多反应监测(MRM)模式测定,内标法定量。结果显示:双酚A在1~50μg/kg范围内呈线性,相关系数为0.9991,加标回收率为98.8%~105.0%,日内和日间相对标准偏差分别为3.84%~8.58%和5.65%~8.74%,检出限为0.3μg/kg,定量限为1.0μg/kg;双酚S在0.4~20μg/kg范围内呈线性,相关系数为0.9995,加标回收率为98.5%~102.5%,日内和日间相对标准偏差分别为3.01%~7.86%和3.18%~7.03%,检出限为0.1μg/kg,定量限为0.3μg/kg。实际样品测定结果分别为:双酚A 2.4~3.8μg/kg;双酚S 0.48~0.82μg/kg。本方法前处理简单、高灵敏度适用于全蛋粉中双酚A和双酚S的日常测定。
基金Project supported by the National Natural Sciences Foundation of China (No. 40371065).
文摘Batch equilibrium experiments were conducted to investigate cadmium (Cd) sorption by two permanent-charge soils, a yellow-cinnamon soil and a yellow-brown soil, and two variable-charge soils, a red soil and a latosol, with addition of selected organic acids (acetate, tartrate, and citrate). Results showed that with an increase in acetate concentrations from 0 to 3.0 mmol L-1, Cd sorption percentage by the yellow-cinnamon soil, the yellow-brown soil, and the latosol decreased. The sorption percentage of Cd by the yellow-cinnamon soil and generally the yellow-brown soil (permanent-charge soils) decreased with an increase in tartrate concentration, but increased at low tartrate concentrations for the red soil and the latosol. Curves of percentage of Cd sorption for citrate were similar to those for tartrate. For the variable-charge soils with tartrate and citrate, there were obvious peaks in Cd sorption percentage. These peaks, where organic acids had maximum influence, changed with soil type, and were at a higher organic acid concentration for the variable-charge soils than for the permanent charge soils. Addition of cadmium after tartrate adsorption resulted in higher sorption increase for the variable-charge soils than permanent-charge soils. When tartrate and Cd solution were added together, sorption of Cd decreased with tartrate concentration for the yellow-brown soil, but increased at low tartrate concentrations and then decreased with tartrate concentration for the red soil and the latosol.