The purpose of this work was to optimize the structure of codrugs for extended delivery across microneedle treated skin. Naltrexone, the model compound was linked with diclofenac, a nonspecific cyclooxygenase inhibitor to enhance the pore lifetime following microneedle treatment and develop a 7 day transdermal system for naltrexone. Four different codrugs of naltrexone and diclofenac were compared in terms of stability and solubility. Transdermal flux, permeability and skin concentration of both parent drugs and codrugs were quantified to form a structure permeability relationship. The results indicated that all codrugs bioconverted in the skin. The degree of conversion was dependent on the structure, phenol linked codrugs were less stable compared to the secondary alcohol linked structures. The flux of naltrexone across microneedle treated skin and the skin concentration of diclofenac were higher for the phenol linked codrugs. The polyethylene glycol link enhanced solubility of the codrugs, which translated into flux enhancement. The current studies indicated that formulation stability of codrugs and the flux of naltrexone can be enhanced via structure design optimization. The polyethylene glycol linked naltrexone diclofenac codrug is better suited for a 7 day drug delivery system both in terms of stability and drug delivery.
这项研究的目的是优化共价药物的结构,以延长微针治疗皮肤的给药时间。模型化合物
纳曲酮与非特异性环
氧化酶
抑制剂双氯芬酸连接,以提高微针处理后的毛孔寿命,并开发出
纳曲酮的 7 天透皮系统。对
纳曲酮和
双氯芬酸的四种不同复方药物的稳定性和溶解性进行了比较。对母药和同系物的透皮通量、渗透性和皮肤浓度进行了量化,以形成结构渗透关系。结果表明,所有同系物都能在皮肤中发生
生物转化。转化程度取决于结构,与仲醇连接的结构相比,
苯酚连接的同系物稳定性较差。
苯酚连接的联名药物在经微针处理的皮肤中的
纳曲酮通量和
双氯芬酸的皮肤浓度更高。聚
乙二醇连接增强了联名药物的溶解度,从而提高了通量。目前的研究表明,可以通过结构设计优化来提高联名药物的制剂稳定性和
纳曲酮的通量。聚
乙二醇连接的
纳曲酮双氯芬酸同系物在稳定性和给药方面都更适合用于 7 天给药系统。