Controlling Mechanical Properties and Dissolution Rate of Strip Films Loaded with Griseofulvin Nanoparticles

Polymer strip films have been demonstrated to be an ideal delivery form for poorly water-soluble drugs. Specifically for active pharmaceutical ingredient (API) particles that have been reduced in size to enhance their solubility and dissolution rate, polymer strip films provide a means by which these nano/micro-size particles can be delivered relatively quickly while retaining their nano/micro size upon delivery. However, the ability to intelligently manipulate the mechanical properties and dissolution rate of such films for the delivery of poorly water-soluble API nanoparticles has yet to be investigated. To this end, hydroxypropyl methylcellulose (HPMC) films were prepared, loaded with model API, griseofulvin, nanoparticles produced via wet stirred media milling in aqueous suspension. These films consisted of various plasticizers and HPMC molecular weights. Addition of glycerin, triacetin, and polyethylene glycol as plasticizers successfully reduced film strength and increased film elasticity with no significant impact on dissolution rate. Increasing the molecular weight of the polymeric film-former generally led to slower film dissolution rate, accompanied by a small increase in tensile strength. All films exhibited good uniformity of content in terms of film thickness and drug distribution (<6% RSD for 0.7 cm² samples). Results demonstrate that, when used in tandem, adjustment of plasticizer content and polymer molecular weight can be used to successfully tailor the mechanical properties and dissolution rate of polymer films loaded with poorly water-soluble drug nanoparticles without sacrificing the advantages or integrity of the strip film format, allowing for intelligent film formulation design for targeted applications.