摘要
以醇为增溶剂,在醇——水介质条件下,药物控制释放行为研究表明,储存器型辐照交联聚硅氧烷——十八甲基炔诺酮(PMVS/LNG)体系的稳态释放,不改变零级动力学机制,控制释放过程的“增速”,使药物“增释”,并讨论了增溶剂浓度及边界层对释放速率的影响。
<ABSTRACT>
It is found that the steady state diffusion release of the controlled re-
lease system of radiation crosslinked PVMS/LNG reservoir follows zero
order kinetics in the common media. This paper studied the solubilizing
extent of ethanol and glycol for LNG in alcohol-water medium. It showed
that the relationship between the saturated concentration of LNG (C ) and
cosolvent concentration (x% ) is a power function, C = A·Bx, in the
volumetrical concentration region of 10-40% ethanol and >5% glycol. Be-
cause of the changes in polarity, the hydration and solubilization effect of
drug are different, their values of A and B being 0.871, 1. 136 and 1.757,
1.059, respectively. The solubilizing extent of ethanol water is almost
constant in the case of >50%.
Under 30: 70 (ethanol: water, volumetrical ratio ) condition, the ex-
perimental results of diffusion release of radiation crosslinked PVMS/LNG
reservior system show that it coincides with zero order kinetics in steady
state period. Because of burst effect and time-lag effect, the initial diffu-
sion release appears a non-steady state. The cosolvent can be regarded as
delivery carrier, its addition causes diffusion coefficient to increase more,
to enhance transportation capability of drug through film, to raise release
rate of drug, and rapid-release the drug.
The diffusion-release rate of drug (J ) and the ethanol concentration
(x% ) in medium is a power function, J = 0. 724·1. 021x. If concentration
of drug in medium maintains saturated state, the release rate is constant.
J = 0. 740. C1/6·1.
In the meantime, the effect of boundary layer on release rate in the di-
ffusion process is studied as well, The results show that the effect of
boundary layer is slight and the release rate is stable, under the ex-
perimental condition, i, e. agitation rate more than 1000rpm,
出处
《中国生物医学工程学报》
CAS
CSCD
北大核心
1989年第4期236-243,共8页
Chinese Journal of Biomedical Engineering
