ABSTRACT
A method for the determination of caffeine in urea was developed based on bubble-in-drop single drop microextraction (BID-SDME) followed by gas chromatography/mass spectrometry (GC-MS).Under the optimum conditions including chloroform as extraction solvent, an exposure volume of 1 μL, a bubble volume of 1.6 μL, stirring for 5 min at 300 r/min, 15% (m/V) NaCl, and a distance of 1 cm between bubble and stirring bar, the detection limit of this method was as low as 0.003 mg/L and the linear range was from 0.005 mg/L to 10 mg/L with correlation coefficient of 0.982.The recoveries of caffeine were from 89.2% to 107.5% at different spiked levels in human urine and the relative standard deviation (RSD, n=6) was less than 8%.
ABSTRACT
In this article, the authors expounded the necessary and problems of animal experiment post-ap-proval monitoring ( PAM) , which included who should do PAM, how to do PAM, and what the PAM can do. The authors also exposed the following suggestion: formulating the detailed rules, regulations and SOP, strengthening the training of PAM team member and animal experiment personnel, and monitoring the whole process of animal protocol review using the software.