建立了高效液相色谱法测定奶粉中双氰胺含量的方法。样品经三氯乙酸沉淀蛋白质和脂肪,在流动相为1.7%磷酸二氢铵的条件下用磺酸基阳离子交换色谱柱（SCX）分离,紫外检测波长218 nm,流速0.8 m L/min,标准曲线法定量。结果表明,双氰胺的...建立了高效液相色谱法测定奶粉中双氰胺含量的方法。样品经三氯乙酸沉淀蛋白质和脂肪,在流动相为1.7%磷酸二氢铵的条件下用磺酸基阳离子交换色谱柱（SCX）分离,紫外检测波长218 nm,流速0.8 m L/min,标准曲线法定量。结果表明,双氰胺的回收率和样品重复测定相对标准偏差分别是97.54%-99.24%和0.01%,方法检测限0.05 mg/kg。该方法无需进行固相萃取,快速灵敏,简便准确,适用于奶粉中双氰胺含量的检测。展开更多
The Cr 6+ in water sample is separated,enriched by low pressure cathodic ion Chromatography and is determined with spectrophotometry.The optimal experimental conditions are also explored.The result is satisfactory in ...The Cr 6+ in water sample is separated,enriched by low pressure cathodic ion Chromatography and is determined with spectrophotometry.The optimal experimental conditions are also explored.The result is satisfactory in that the instruments and equipment used in experiment are ordinary,the manipulation is easy,other cations in water sample don’t interfere in the determination of Cr 6+ and the multiplicity of enrichment may reach 100 Limit concentration being 1.06×10 -4 mg/L,RSD 0.1%,rate of recovery,97.9～103.8.展开更多
文摘建立了高效液相色谱法测定奶粉中双氰胺含量的方法。样品经三氯乙酸沉淀蛋白质和脂肪,在流动相为1.7%磷酸二氢铵的条件下用磺酸基阳离子交换色谱柱（SCX）分离,紫外检测波长218 nm,流速0.8 m L/min,标准曲线法定量。结果表明,双氰胺的回收率和样品重复测定相对标准偏差分别是97.54%-99.24%和0.01%,方法检测限0.05 mg/kg。该方法无需进行固相萃取,快速灵敏,简便准确,适用于奶粉中双氰胺含量的检测。
文摘The Cr 6+ in water sample is separated,enriched by low pressure cathodic ion Chromatography and is determined with spectrophotometry.The optimal experimental conditions are also explored.The result is satisfactory in that the instruments and equipment used in experiment are ordinary,the manipulation is easy,other cations in water sample don’t interfere in the determination of Cr 6+ and the multiplicity of enrichment may reach 100 Limit concentration being 1.06×10 -4 mg/L,RSD 0.1%,rate of recovery,97.9～103.8.
