X射线荧光光谱法快速定量桂利嗪片中7种元素杂质

目的对桂利嗪片中镉(Cd)、铅(Pb)、砷(As)、汞(Hg)、钴(Co)、钒(V)、镍(Ni)7种元素杂质进行快速定量和风险评估。方法样品无须预处理,采用能量色散型X射线荧光光谱法测定11家生产企业的17批桂利嗪片中7种元素杂质的含量。电压为50 kV,电流为100μA,氛围为空气,测试时间为3100 s。结果Cd,Pb,As,Hg,Co,V,Ni元素的质量浓度分别在0~16.6 mg/kg、0~16.6 mg/kg、0~50 mg/kg、0~100 mg/kg、0~166.6 mg/kg、0~333.5 mg/kg、0~667 mg/kg范围内与待测元素和校正元素的荧光强度比值线性关系良好(r≥0.9990);平均回收率分别为93.75%,80.00%,90.17%,82.28%,112.79%,115.60%,104.71%;定量限分别为0.578,1.090,0.281,0.625,0.364,1.747,1.534 mg/kg。17批桂利嗪片中上述7种元素的含量均低于控制阈值,未发现风险。结论该方法操作简便,可直接快速定量桂利嗪片中7种元素杂质,适用于口服固体制剂桂利嗪片中元素杂质的风险评估。

Possible Relevance of the Allende Meteorite Conditions in Prebiotic Chemistry: An Insight into the Chondrules and Organic Compounds

The study of the mineral and organic content of the Allende meteorite is important for our understanding of the molecular evolution of the universe as well as the ancient Earth. Previous studies have characterized the magnetic minerals present in ordinary and carbonaceous chondrites, providing information on the evolution of magnetic fields. The interaction of organic compounds with magnetic minerals is a possible source of chemical diversity, which is crucial for molecular evolution. Carbon compounds in meteorites are of great scientific interest for a variety of reasons, such as their relevance to the origins of chirality in living organisms. This study presents the characterization of organic and mineral compounds in the Allende meteorite. The structural and physicochemical characterization of the Allende meteorite was accomplished through light microscopy, powder X-ray diffraction with complementary Rietveld refinement, Raman and infrared spectroscopy, mass spectrometry, scanning electron microscopy, and atomic force microscopy using magnetic signal methods to determine the complex structure and the interaction of organic compounds with magnetic Ni-Fe minerals. The presence of Liesegang-like patterns of chondrules in fragments of the Allende structure may also be relevant to understanding how the meteorite was formed. Other observations include the presence of magnetic materials and nanorod-like solids with relatively similar sizes as well as the heterogeneous distribution of carbon in chondrules. Signals observed in the Raman and infrared spectra resemble organic compounds such as carbon nanotubes and peptide-like molecules that have been previously reported in other meteorites, making the Mexican Allende meteorite a feasible sample for the study of the early Earth and exoplanetary bodies.