微波萃取高效液相色谱法测定口红中芳香胺类化合物

利用微波萃取高效液相色谱法测定了口红中芳香胺类化合物.先将口红涂于玻璃片上,然后用微波萃取和高效液相色谱法测定萃取液中的芳香胺类化合物.研究了3种市售口红并得到了芳香胺类化合物的定量测定结果.考察了微波萃取的条件,并将薄层色谱等萃取分离方法和微波萃取法进行了比较,证明微波萃取法在萃取膏状物和蜡状物中的组分时,具有比其它方法更加方便、快速等优点.

Interaction Between CdS Nanoparticles and Cysteine

CdS nanoparticles were synthesized and their spectra properties were studied. At the same time, the interaction mechanisms between CdS nanoparticles and cysteine and cysteine were investigated under different experimental conditions such as pH values, concentrations of cysteine and molar ratios of CdCl-2, CH-3CSNH-2. After cysteine being added to the CdS nanoparticles, the fluorescence intensity of CdS nanoparticles was stronger and their emission peak did not change at pH before isoelectric point, while the fluorescence intensity became stronger at the beginning and then quenched and the emission peak was red-shifted at pH values after isoelectric point. It's proved that coordination interaction and electrostatic interaction were the two interaction forms between CdS and cysteine, which influenced the variations of fluorescence intensity, emission peak and bandgap of CdS nanoparticles at different pH balues before and after isoelectric point.