Professor Florida A & M University Tallahassee, Florida
Transdermal/Topical adhesive product development is a complex process and required optimal balance between adhesive and cohesive forces to achieve optimized transdermal formulation. The exposure of transdermal formulation to various extrinsic and intrinsic factors causes the imbalance in these forces and also a lack of understanding of skin-adhesive interfacial interactions has led to failures of many patches (e.g. Rotigotine (Neupro), Rivastigmine (Exelon), and Clonidine (Catapres)). These patches fall off earlier than their prescribed time duration and hence fail in the marketplace. The causative factors for these failures may be attributed to changes in adhesive properties of the components used in the patch (adhesives, permeation enhancers, polymers) and the interfacial changes (between the skin and patch) occurring as a function of temperature, humidity, and other extraneous factors. Surprisingly, no detailed study has been conducted to understand the physicochemical changes occurring in the patch components or the skin as a function of time, storage, and the impact of extrinsic factors. Furthermore, the current in-vitro method of evaluation are based on stainless steel probe which have a higher surface energy (>700 dyne/cm) than skin and hence may not be very predictive of adhesion properties of the transdermal products. Moreover, conditions of skins such torsion, flexion, micro delamination and flakiness may lead to adhesion failure of the patches. Therefore, it is important to develop skin mimetic surfaces having skin-like properties and topographical features. Therefore, our objective was to improve the in-vitro adhesion testing of the transdermal products by fabricating probes with similar surface energy as human skin using 3D printing additive manufacturing technology for the better prediction of in vitro in vivo correlation (IVIVC).
Learning Objectives:
Upon completion participants will be able to learn about 3D printing technology in topical adhesion testing and a newer method to evakluate adhesion testing
Upon completion, participants would be able to understand the role of surface energy of the skin in adhesion testing.
Upon completion, participants would be able to understand the role of various 3D printers and materials in making appropriate probes for their applications in adhesion testing.
The role of 3D printing in generating probes which can simulate delamination or wrinkled skin
The audience will be exposed to role of robotics in post-processing of probes