Preparation Of Chitosan-Based Microneedles For Transdermal Drug Delivery

Abstract

Dissolving microneedles have gained interest due to their ability to encapsulate and release drug formulations upon dissolution. These devices are composed of soluble materials or biodegradable polymers, allowing controlled drug delivery. Chitosan, a significant component in dissolving microneedles, has been widely used due to its high biodegradability and biocompatibility. However, studies have yet to explore how the molecular weight of chitosan affects transdermal distribution utilizing dissolving microneedles. This research aimed to study the impact of chitosan molecular weight on the fabrication of chitosan microneedles for transdermal drug delivery. Nine microneedle types were fabricated using Polyvinyl alcohol /polyvinylpyrrolidone (PVA/PVP) solution as a supporting base, yielding nine different microneedle types. The study compared morphologies, characteristics, mechanical properties, skin insertion, cytotoxicity, and drug release profiles using Rhodamine B as the model drug. This information can be applied to the formulation of dissolving microneedles for transdermal drug delivery. Chitosan from different molecular weights and concentrations was successfully fabricated into microneedles using the double-casting method. The shape, mechanical strength, and insertion characteristics of chitosan microneedles were greatly influenced by their molecular weight. At 3%(w/v) concentrations, low, medium, and high molecular weight chitosan microneedles demonstrated high mechanical strength. With an insertion depth of 0.52 mm, the 3% light weight chitosan microneedle (3LW) displayed the greatest skin penetration through PARAFILM. 3LW demonstrated the highest mechanical strength and insertion properties. It was utilized to analyze the cytotoxicity and drug release profile of the microneedles. Within 10 minutes, there was an initial burst release, which was followed by a slow release over time. At a concentration of 3% (w/v), which was used to form 3LW, low-weight chitosan was found to be low-toxic.