Electrospun cellulose acetate fiber mats containing herbal substances for drug delivery system and wound dressing applications

Abstract

Ultra-fine cellulose acetate (CA; Mw ≈ 30,000 Da; degree of acetyl substitution ≈ 2.4) fiber mate containing either curcumin (CM; from the plant Curcuma longa L.) or asiaticoside (Ac; from the plant Centella asiatica L. either in the form of pure substance (PAC) or a crude extract (CACE)), widely known for anti-tumor, antioxidant, anti-inflammatory, and wound healing properties, were successfully prepared by electrospinning. Incorporation of herbal substances in the neat CA solution did not affect the morphology of the resulting fibers, as both the neat and the herb-loaded CA fibers were smooth. The average diameters of these fibers ranged between 301 and 545 nm. Chemical integrity of the herbal substance within the herb-loaded CA fiber mats, mechanical integrity, and swelling and weight loss behavior of neat and herb-loaded CA fiber mats were studied. Moreover, the investigation of the release characteristics of herbal substances from herb-loaded CA fiber mats was carried out by the total immersion and the transdermal diffusion through a pig skin method in buffer solution. The potential for user of these electrospun fiber mats as wound dressings was further assessed in vitro with human dermal fibroblast (NHDF) cells in terms of the indirect cytotoxicity, the antioxidant activity, the cell attachment, the cell proliferation, and the collagen quantification. In addition, the morphological observation of culture cells on these electrospun fiber mats was also investigated by scanning electron microscopy (SEM).