Design And Research Of Drug Loading Pressure-sensitive Adhesives Patch Model

Drug loading pressure-sensitive adhesives is a kind of medical product which treat patients directly through in vitro transdermal drug delivery system. Taking pressure-sensitive adhesives as its drug carrier, the drug is stored in pressure-sensitive adhesives matrix. Taking local transdermal drug delivery as its drug-delivery way, it is easy to use and is applied widely in medicine field. A drug loading pressure-sensitive adhesives model with methyl salicylate as drug model and ESIS type pressure-sensitive adhesives as earner is designed and the optimal formulation of the model is established in this thesis. And its properties have been researched in detail in this thesis. The main work includes:Drug loading pressure-sensitive adhesives model was prepared successfully by heating and blending with ESIS as matrix material, methyl salicylate as release drug, epoxy soybean oil as plasticizer and hydrogenated rosin as tackifier. And the optimal mechanical property formulation of the model was acquired by using orthogonal method. The optimal formulation is m(methyl salicylate):m(ESIS):m(epoxy soybean oil):m(high hydrogenated rosin):m(antioxidant 1010)=15:100:80 100:0.005. The impact of antioxidant on the thermostability of patch, theimpact of methyl salicylate content on the mechanical property of patch and the compatibility condition between methyl salicylate and ESIS pressure-sensitive adhesives have been studied in this thesis. The result showed that the thermostability of model patch with antioxidant was significantly better than that of model patch without antioxidant under the same conditions. Thus, antioxidant was added in this model. With the increase of methyl salicylate content, the holding power and peeling strength of patch were both weakened. When methyl salicylate content exceeded 35%, the mechanical property of patch can not conform to the requirements for use. Meanwhile in order to make model patch release drug stably, excessive releaser is designed to be stored in matrix to act as a drug storeroom. When methyl salicylate content exceeded 5%, it meet this requirement. And its transmission electron microscope image can also demonstrate this well. Thus, it is decided to study the next release property and safety on the condition that methyl salicylate content is between 5% to 35%.In the experiment of percutaneous absorption in vitro performed on mice by using ready-prepared methyl salicylate pressure-sensitive adhesives, methyl salicylate testing method was determined by referring to Pharmacopoeia of the People’s Republic of China, in vitro release process of this drug loading patch and the impact of methyl salicylate content on the release property of patch were studied, and the patch releasing mechanism was acquired. The results showed that in the patch whose methyl salicylate content exceeded 15%, cumulative release amount of methyl salicylate was on the rise during the first 4 hours and became steady after 4 hours, which meet the requirement of stable release. With the increase of methyl salicylate content, cumulative release amounts at the same point in time were also on the rise and it took less time to achieve stable release condition. The fitting result of methyl salicylate pressure-sensitive adhesives within 4 hours is Q=6.13t0.5-7.28 R-=0.9943 which complied with the Higuchi equations. The fitting result of methyl salicylate pressure-sensitive adhesives after 4 hours isQ=39.2t0.6+1.78 R2=0.9952, and drug release belongs to non-fick release. Taking overall consideration of release property and mechanical property, the optimal formulation of methyl salicylate pressure-sensitive adhesives was finally determined as m(methyl salicylate):m(ESIS) m(epoxy soybean oil):m(high hydrogenated rosin):m(antioxidant 1010) =15:100:80:100:0.005.Finally, safe property of methyl salicylate pressure-sensitive adhesives was tested through skin stimulative experiment and skin allergy experiment respectively. The results showed:methyl salicylate pressure-sensitive adhesives designed in this thesis has no irritation and sensitization to skin. It can be used safely.