Blends of shellac as nanofiber formulations for wound healing

Abstract

Shellac is being used in food, pharmaceutical, and agricultural industries. It is seldom used for biomedical applications due to its poor mechanical property and instability. We designed thermoresponsive shellac-based bioactive nanofiber mats that mimic extracellular matrix to extend their utility in wound healing. Various blend compositions of shellac, gelatin, and poly(N-isopropylacrylamide) enriched with a bioactive agent, nadifloxacin, were prepared and nanofiber mats were fabricated. The morphology of the nanofiber formation was influenced by the concentration of polymer, drug, and polymer blend composition. Polymer–drug interactions and thermal and crystalline properties of nanofiber mats were analyzed. The shellac/gelatin/poly(N−isopropylacrylamide) blend of composition 3%/7%/3% (w/v) was chosen to evaluate in vitro drug release. Release studies recorded slow, constant, and sustained release for 140 h. The release kinetics and mechanism confirmed zero-order release with resultant r2 values greater than 0.99, and the Korsmeyer–Peppas release exponent (n) was slightly higher than 0.8, which indicated that drug diffusion was anomalous or non-Fickian type and drug release followed diffusion involving chain stretching. Indirect cytotoxicity studies recorded insignificant toxicity against normal human fibroblast cells. In vivo studies demonstrated that drug-loaded nanofiber mats were more suitable for faster tissue regeneration as compared to nanofiber mats without drug and commercial nadifloxacin cream.

Proteins as Nanocarriers To Regulate Parenteral Delivery of Tramadol

“…Further, the Korsmeyer–Peppas release exponent ( n ) is not uniform for all the formulations, where the formulation F followed anomalous behavior or non-Fickian diffusion, because n is less than 0.5, indicating the rate of solvent diffusion and polymer chain stretching are comparable. 35 So the release of Td was dependent on diffusion of solvent and chain stretching. Meanwhile, the other two formulations followed a Fickian type of diffusion where n < 0.5, so it indicates that the diffusion of solvent was slower than chain stretching due to increased functional interactions between the drug molecules and the polymer chains of the EA.…”

Multiscale Shellac-Based Delivery Systems: From Macro- to Nanoscale

“…In addition, the −OH, −COOH, and −CHO contained in shellac molecules facilitate the surface modification of shellac nanoparticles, which is of great significance for expanding their drug delivery applications. Shellac nanofibers are another shellac-based nanodelivery system obtained by electrospinning. , Generally, both pure shellac and its mixture with other polymers can achieve excellent applicability for electrospinning applications . Core–shell shellac-based nanofibers can also be fabricated using coaxial electrospinning .…”

“…213 The incorporation of PVP also improves the mechanical properties and drug loading capacity of shellac fibers and increases its dissolution rate through rapid erosion. 72 Vannuruswamy et al 34 found that nanofiber mats formed from a shellac/gelatin/poly(Nisopropylacrylamide) blend had a lower hydrophobicity than shellac nanofiber mats. The blended nanofiber mats achieved 140 h of sustained drug release of drugs with zero-order kinetics.…”

“…31 Shellac-based microparticles (beads/spheres), another microlevel delivery system, can encapsulate the active substances in the network structure formed by shellac molecules through hydrophobic and hydrogen-bond interactions, thus protecting active substances from degradation, controlling the release of active substances, and increasing compliance. 32 Furthermore, shellac-based nanolevel delivery systems, including nanoparticles 33 and nanofibers, 34 have good biodegradability, biocompatibility, and higher surface-to-volume ratio, which can effectively encapsulate hydrophobic and unstable active substances for oral administration or wound dressing. The scale of a shellacbased delivery system is critical to its performance and application.…”

Cellulose acetate/poly(vinyl alcohol) hybrid fibrous mat containing tetracycline hydrochloride and phenytoin sodium: Morphology, drug release, antibacterial, and cell culture studies

“…It was supposed that PVA in aqueous media such as wound exudate would be a fast disintegrated matrix showing a burst release manner, while CA would be a more stable matrix and it was showing a gradual drug release behavior. Tetracycline hydrochloride (TC) as a well-known antibiotic and phenytoin sodium (PHT-Na) as an accelerating drug for cell growth [64][65][66] were loaded into CA and PVA solutions, respectively. Each of polymer solutions (with or without drug) was injected via one syringe placed in opposite directions in an electrospinning apparatus and fibers were collected on an aluminum target.…”