[Study on alpha-asarone reservoir-type patch].
OBJECTIVE
To prepare the alpha-asarone reservoir patch and investigate its release and transdermal absorption characteristics in vitro. The efficient enhancers were chosen to improve the drug's permeation rate.


METHODS
The alpha-asarone reservoir patch was prepared using 1% hydroxypropyl methylcellulose (HPMC) of ethanol solution as medium and ethylene vinyl acetate (EVA) membrane to control the release of drug. The Franz diffusion cells were used and several permeation enhancers were evaluated. High performance liquid chromatorgraphy (HPLC) was used to determine alpha-asarone's content and permeation rate.


RESULTS
The release mechanisms of alpha K-asarone patch in vitro coincided with zero-order kinetic. 30% ethanol cooperates with 1% Isopropyl Myristate (IPM) have the best effect on permeation of the patch. The permeation rate reaches (20.67 +/- 1.33) microg x cm(-2) h(-1).


CONCLUSIONS
Ethanol combined with IPM is good permeation enhancer, which facilitated the permeation of alpha K-asarone to fit the clinical requirements. However, the further studies of the skin's stimulation and bioavailability are needed.
Wu
Zheng
Z
Institute of pharmaceutics, Zhe jiang University, Hangzhou 310058, China.
Gao
Jian-Qing
JQ
Chen
Hai-Liang
HL
Hu
Ying
Y
Liang
Wen-Quan
WQ
D029023:Acorus / Q000737:chemistry*; D000279:Administration, Cutaneous; D000081248:Allylbenzene Derivatives; D000840:Anisoles / Q000008:administration & dosage / Q000302:isolation & purification / Q000493:pharmacokinetics*; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000431:Ethanol / Q000494:pharmacology; D006801:Humans; D065347:Hypromellose Derivatives; D066298:In Vitro Techniques; D008747:Methylcellulose / Q000031:analogs & derivatives / Q000737:chemistry; D009226:Myristates / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry; D011145:Polyvinyls / Q000737:chemistry; D012867:Skin / Q000187:drug effects / Q000378:metabolism*; D012869:Skin Absorption / Q000187:drug effects
D000081248:Allylbenzene Derivatives; D000840:Anisoles; D003692:Delayed-Action Preparations; D009226:Myristates; D011145:Polyvinyls; C012195:asarone; C008205:isopropyl myristate; C016438:ethylenevinylacetate copolymer; D000431:Ethanol; D065347:Hypromellose Derivatives; D008747:Methylcellulose