[The aquation of oxaliplatin and the effect of acid].
OBJECTIVE
To investigate the aquation of oxaliplatin in aqueous solution at different temperatures and gain the kinetic data.


METHODS
Electronic conductometry and high performance liquid chromatography (HPLC) were used to measure the oxaliplatin content in the reaction systems at different time.


RESULTS
The aquation of oxaliplatin followed a pseudo-first-order rate law. In the absence of H+, the observed rate constant kobs was 7.76 x 10(-6).min-1 and the half life t1/2 was 62 days at 25 degrees C. In the presence of H+, the aquation could be accelerated by H+ according to the equation kobs = (2.61 + 21.9 [H+]) x 10(-4).min-1. The mechanism of aquation has also been proposed in this paper. From the mechanism, the rate of aquation following to r = (k1 k2) [l-OHP]/k-1 in the absence of H+ and r = (k1 + K0k3 [H+]) [l-OHP] in the presence of H+ have been deduced, which were in perfect agreement with the experimental results.


CONCLUSIONS
In the absence of H+, the aqueous solution of oxaliplatin is stable, which meets to the request of clinical.
Gao
Wen-gui
WG
Kunming Institute of Precious Metals, Kunming 650221, China. gaowengui@ipm.com.cn
Pu
Shao-ping
SP
Liu
Wei-ping
WP
Liu
Zhu-dong
ZD
Yang
Yi-kun
YK
D000143:Acids; D000970:Antineoplastic Agents / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009944:Organoplatinum Compounds / Q000737:chemistry*; D000077150:Oxaliplatin; D012996:Solutions; D014867:Water / Q000737:chemistry*
D000143:Acids; D000970:Antineoplastic Agents; D009944:Organoplatinum Compounds; D012996:Solutions; D000077150:Oxaliplatin; D014867:Water