Influence of nanofiber alignment on the release of a water-soluble drug from cellulose acetate nanofibers

Cellulose acetate nanofibers with different degrees of alignment (randomly aligned (RA), partially aligned (PA), and highly aligned (HA)) were produced using an electrospinning technique. The different degrees of alignment were obtained by adjusting the rotation speed of the collector. Alpha-arbutin (3% w/w) employed as a model water-soluble compound was incorporated into the nanofibers during the fabrication process. The drug release characteristics were investigated using the nanofiber mats with the same size and weight. The prepared nanofibers with different degrees of alignment showed similar physical characteristics, including the fiber diameter, drug loading efficiency and capacity, and molecular form of the drug in the fibers. Interestingly, alpha-arbutin was released from HA nanofibers at a significantly faster rate than the PA and RA nanofibers. Eighty percent of the drug was released into the medium in 1.7, 4.2, and 9.4 min for HA, PA, and RA nanofibers, respectively. The orientation of nanofibers played a crucial role in governing the drug release, probably by creating network meshes with different degrees of entanglement, affecting the diffusion of drug to the external medium. Consequently, this approach can be used as a simple means of achieving immediate-release or fast-acting characteristics of cellulose-based formulations containing a water-soluble drug.