The real-time in vivo measurement method has been urgently needed in the research of pharmacokinetics. In the present paper a new in vivo detection method based on fluorescence spectroscopy has been proposed and the monitoring system has been built which is used for pharmacokinetics studies in rats. The relationship between fluorescence intensity and concentration was obtained. By detecting the fluorescent dye Cypate in real-time in rats, the properties of the system have been validated by comparing with the fluorescence imaging system in vitro. The results showed that the system could be feasible for: (1) The linear regression equation of Cypate concentration in the range of 0.098-25 microg/ml is y = 73.249x + 130.97 (R2 = 0.9991 and P < 0.001). RSD of high, medium and low concentration is 1.23%, 6.29% and 13.48%, respectively, and the detecting sensitivity is 0.0981 g/ml; (2) The fluorescent dye concentration from the system is consistent (r = 0.9925) with the fluorescence imaging system in vitro. The fluorescent dye metabolism in rats can be well detected. It can be concluded that a new real-time in vivo detecting method in the paper can be used in pharmacokinetics research.
Animals ; Fluorescent Dyes ; pharmacokinetics ; Rats ; Spectrometry, Fluorescence ; methods ; Spectroscopy, Near-Infrared ; methods