目的建立反相高效液相色谱法测定头孢地尼及制剂中的聚合物杂质。方法以CAPCELL PAK C_(18)MGⅡ为色谱柱(250 mm×4.6 mm,5μm),0.25%四甲基氢氧化铵溶液(p H 5.5)[每1000mL中加入0.1 mol/L乙二胺四乙酸二钠溶液0.4 mL]-甲醇-乙腈...目的建立反相高效液相色谱法测定头孢地尼及制剂中的聚合物杂质。方法以CAPCELL PAK C_(18)MGⅡ为色谱柱(250 mm×4.6 mm,5μm),0.25%四甲基氢氧化铵溶液(p H 5.5)[每1000mL中加入0.1 mol/L乙二胺四乙酸二钠溶液0.4 mL]-甲醇-乙腈为流动相系统,梯度洗脱,建立了头孢地尼聚合物类杂质的分析方法并进行了方法学验证。采用二维液质联用法对检出的聚合物类杂质进行定性分析。结果在该色谱条件下头孢地尼及已知杂质均与头孢地尼聚合物间分离良好,头孢地尼检测浓度的线性范围为0.30~30.1μg/mL(r=1.0000),方法的检测限与定量限分别为1.5 ng和4.5 ng。所建立的方法能够检出头孢地尼二聚体,头孢地尼二聚体的多个同分异构体及头孢地尼三聚体。结论本方法专属性好,灵敏度高,耐用性好,可用于头孢地尼及其制剂中聚合物杂质的控制。展开更多
Milk fat contains a variety of nutritive and health-promoting compounds that guard against some disease. In the current system of global competition, when the quality of milk and milk products is not an option but rat...Milk fat contains a variety of nutritive and health-promoting compounds that guard against some disease. In the current system of global competition, when the quality of milk and milk products is not an option but rather a requirement, therefore, determining the purity of milk fat is critical. This study aims to validate analytical methods for detecting palm oil in a mixture of milk fat and palm oil. Methods of this study was involved detection of non-milk fat in fat blinders by determining the saponification value, iodine number, refractive index, butyro refractometer reading, Gas chromatography, Reverse Phase High-performance liquid chromatography, and Fourier transforms Infrared. The results of this study revealed that the saponification value, Iodine number, refractive index, and Butyro Reading could be used to detect the addition of palm oil by a level of 10% - 20% or more to the milk. The level of some fatty acids in the milk as determined by GC, such as myristic acid (C14:0), palmitic acid (C16:0), and stearic acid (C18:0), is correlated well with the level of adding palm oil to milk fat. The determination of cholesterol and β-sito-sterol content by RP-HPLC could be used for the detection of the addition of palm oil to milk fat. The spectrum behavior produced by FTIR spectroscopy in this adulterated sample is almost the same, so this technique could not be used to detect the palm oil in milk fat.展开更多
文摘Milk fat contains a variety of nutritive and health-promoting compounds that guard against some disease. In the current system of global competition, when the quality of milk and milk products is not an option but rather a requirement, therefore, determining the purity of milk fat is critical. This study aims to validate analytical methods for detecting palm oil in a mixture of milk fat and palm oil. Methods of this study was involved detection of non-milk fat in fat blinders by determining the saponification value, iodine number, refractive index, butyro refractometer reading, Gas chromatography, Reverse Phase High-performance liquid chromatography, and Fourier transforms Infrared. The results of this study revealed that the saponification value, Iodine number, refractive index, and Butyro Reading could be used to detect the addition of palm oil by a level of 10% - 20% or more to the milk. The level of some fatty acids in the milk as determined by GC, such as myristic acid (C14:0), palmitic acid (C16:0), and stearic acid (C18:0), is correlated well with the level of adding palm oil to milk fat. The determination of cholesterol and β-sito-sterol content by RP-HPLC could be used for the detection of the addition of palm oil to milk fat. The spectrum behavior produced by FTIR spectroscopy in this adulterated sample is almost the same, so this technique could not be used to detect the palm oil in milk fat.