Study on in vitro release of diclofenac sodium patches by reciprocating holder method

XIANG Meng-ru; LI Xian-qing; DU Wei-feng; WU Hong; XIE Zi-li

doi:10.20251/j.cnki.1003-3734.2025.14.014

Abstract：Objective:To determine the dissolution profile of diclofenac sodium patches using the reciprocating holder method and fit a model to the dissolution data.Methods:The 24 h in vitro release of diclofenac sodium patches were investigated by the reciprocating holder method with different media(phosphate buffer pH 6.8,7.0,7.4 and saline),different reciprocating frequencies(15,30 and 45dip·min-1),and different materials of double-sided adhesive tape(3M-VHB material,3M-PET material,and 3M-nonwoven material).The drug content was determined by HPLC,and the Zero order,First order,Weibull,Korsmeyer-Peppas and Higuchi models were fitted to the dissolution data by DDsolver software to identify the optimal release model.Results:The optimal release test condition of diclofenac sodium patches were as follows:the patches were fixed with cylinder sample rack and 3M non-woven double-sided tape,the reciprocating frequency was 30 dip·min-1,the amplitude was 2 cm,and the dissolution medium was phosphate buffer(pH 7.4)with a volume of 800 mL.The cumulative release amount(%)of the three batches within 24 h were(55.44±1.74)%,(52.34±1.04)%,(65.39±1.38)%,respectively.The optimal release model was Weibull model,the release equations were F=100×{1-Exp[-((t+0.130)0.739)/13.158]},F=100×{1-Exp[-((t+1.021)0.720)/13.791]},F=100×{1-Exp[-((t-0.481)0.629)/6.911]},and the correlation coefficients r2 were 0.999 3,0.999 1 and 0.997 7,respectively.Conclusion:The reciprocating holder method can be used for the determination of the release degree of diclofenac sodium patches,which is simple to operate,and the results are accurate and reliable,providing a reference for the quality study of related patches using the reciprocating holder method.