3-APTES modified graphene oxide strengthened dissolving polymer microneedle arrays for transdermal delivery

Abstract

Dissolving polymer microneedle arrays have been widely used in transdermal delivery of molecules since 2008 due to their ease of fabrication and great biocompatibility. It has been reported that the microneedle arrays can be used in biomedical, cosmetic and industrial fields such as vaccine delivery. However, pure dissolving polymers generally have weak mechanical properties, which is an inherent problem in using the fabricated microneedle arrays for transdermal delivery. To address the issue, one strategy is to add nanomaterials to polymers for the formation of nanocomposites for improved properties. In this report, different graphene oxide (GO) derivatives were incorporated into carboxymethylcellulose sodium (CMC) under various conditions and various properties were investigated. The Young’s modulus and hardness of the samples were measured by nanoindentation and micro tensile test. The thermal properties were determined using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The result indicated that the nanocomposite containing 3-aminopropyltriethoxysilane (3-APTES) modified GO in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/ N-hydroxysuccinimide (EDC/NHS) displays a significant improvement of mechanical properties in comparison with pure polymer , and there was an increase of 118% and 185% of that nanocomposite from 0 wt% to 5 wt% in terms of Young’s Modulus and hardness respectively. Moreover, other nanocomposites like 3-APTES modified GO/CMC without EDC/NHS and GO/ CMC thin films from 0 wt% to 5 wt% were also shown different degrees of enhancement of mechanical properties compared with pure CMC polymer. Afterwards, the most of CMC polymer microneele arrays with different GO nanocomposites fabricated were shown the accurate shades and sizes by the observation of scanning electron microscope (SEM).