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Yang D.,Shanghai Ocean University | Zhao X.,China Pharmaceutical University | Zhao X.,Shanghai Key Laboratory for Pharmaceutical Chinese Materia Medica Metabolite Research | Sun F.-L.,China Pharmaceutical University | And 6 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2014

This paper studied the fluorescence spectral characteristic of chlorin e6-C15-monomethyl ester in different solvents to develop a fluorescence spectrometry for determining the concentration of chlorin e6-C15-monomethyl ester in plasma. By comparing the fluorescence spectral characteristics of chlorin e6-C15-monomethyl ester in six different solvents including methanol, ethanol, acetone, acetonitrile, phosphate buffered saline and water, the influence of different solvents on the fluorescence spectral characteristic of chlorin e6-C15-monomethyl ester has been examined. The results indicated that methanol and acetonitrile are the ideal solvent system, and the effect of phosphate buffered saline is better than water. The effect of organic solvent content and solution pH value on emission wavelength and fluorescence intensity was further evaluated. It was found that the fluorescence intensity of chlorin e6-C15-monomethyl ester was strong and stable in pH 7.2 phosphate buffered saline-acetonitrile (3:7) solution and can be detected at the excitation wavelength of 498.00 nm and the emission wavelength of 664.05 nm. Based on this, we developed the fluorescence spectrometry for determining chlorin e6-C15-monomethyl ester. It is specific and sensitive with good linearity over the range of 0.5~50 μg·mL-1. The intra-batch and inter-batch precisions (RSD) were less than 10%, the extraction recoveries were all over 90%. The established method in this paper was simple, fast, effective and could be successfully applied to study the pharmacokinetics of chlorine e6-C15-monomethyl ester in SD rats.

Wang X.-Y.,Fujian University of Traditional Chinese Medicine | Fang J.-C.,China Pharmaceutical University | Fang J.-C.,Shanghai Key Laboratory for Pharmaceutical Chinese Materia Medica Metabolite Research | Yang G.,China Pharmaceutical University | And 8 more authors.
Academic Journal of Second Military Medical University | Year: 2014

Objective To establish a method for determining the recovery of rocuronium microdialysis probe by LC-MS/MS, so as to investigate the stability and reproducibility of microdialysis probe recovery during in vivo and in vitro microdialysis trials and to provide evidence for in vivo microdialysis. Methods The concentration of rocuronium in dialysate was determined by LC-MS/MS and the probe recovery was calculated.The effects of different drug concentrations (50, 200, and 500 ng/mL) and flow rates(0.5, 1.0, 2.0, 3.0, and 4.0 μL/min)on the probe recovery were determined by incremental (dialysis) and reduction (retrodialysis) methods. The in vivo probe recovery in SD rats was determined by reduction method, and its result was compared with that of the in vitro trial. Results The in vitro probe recovery decreased with the increase of flow rate within a range of 0.5-4 μL/min under the same condition. At the same flow rate, different concentrations of rocuronium had little influence on the probe recovery. Under the same condition, the in vitro recovery obtained by incremental and reduction methods were approximately equal and showed a good stability. The in vivo probe recovery obtained by reduction method was similar to the in vitro one. Conclusion Microdialysis can be used for pharmacokinetic study of rocuronium, and retrodialysis method can be used to study probe recovery of rocuronium in vivo. © 2015, Second Military Medical University Press. All rights reserved.

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