Bioresorbable nanofiber‐based systems for wound healing and drug delivery: Optimization of fabrication parameters

Abstract

Wound healing is a complex process that often requires treatment with antibiotics. This article reports the initial development of a biodegradable polymeric nanofiber-based antibiotic delivery system. The functions of such a system would be (a) to serve as a biodegradable gauze, and (b) to serve as an antibiotic delivery system. The polymer used in this study was poly(lactide-co-glycolide) (PLAGA), and nanofibers of PLAGA were fabricated with the use of the electrospinning process. The objective of this study was to determine the effect of fabrication parameters: orifice diameter (needle gauge), polymer solution concentration, and voltage per unit length, on the morphology and diameter of electrospun nanofibers. The needle gauges studied were 16 (1.19 mm), 18 (0.84 mm), and 20 (0.58 mm), and the range of polymer solution concentration studied was from 0.10 g/mL to 0.30 g/mL. The effect of voltage was determined by varying the voltage per unit electrospinning distance, and the range studied was from 0.375 kV/cm to 1.5 kV/cm. In addition, the mass per unit area of the electrospun nanofibers as a function of time was determined and the feasibility of antibiotic (cefazolin) loading into the nanofibers was also studied. The results indicate that the diameter of nanofibers decreased with an increase in needle gauge (decrease in orifice diameter), and increased with an increase in the concentration of the polymer solution. The voltage study demonstrated that the average diameter of the nanofibers decreased with an increase in voltage. However, the effect of voltage on fiber diameter was less pronounced as compared to polymer solution concentration. The results of the areal density study indicated that the mass per unit area of the electrospun nanofibers increased linearly with time. Feasibility of drug incorporation into the nanofibers was demonstrated with the use of cefazolin, a broad-spectrum antibiotic. Overall, these studies demonstrated that PLAGA nanofibers can be tailored to desired diameters through modifications in processing parameters, and that antibiotics such as cefazolin can be incorporated into these nanofibers. Therefore, PLAGA nanofibers show potential as antibiotic delivery systems for the treatment of wounds.

Forming of Polymer Nanofibers by a Pressurised Gyration Process

“…Generally, a lower concentration promotes bead or droplet formation and a higher concentration results in polymer melt where extrusion of fi bers is diffi cult or promotes thicker fi ber formation. [ 19 ] Surface tension and the viscosity of the polymer solution were measured using a KRUSS Tensiometer and a Brookfi eld viscometer, respectively. The measured values of surface tension were 50, 52, and 57 mNm − 1 and the measured values of viscosity were 75, 2200 and 3000 mPa s for 5, 15, and 21 wt% of PEO solutions, respectively.…”

Beads, beaded-fibres and fibres: Tailoring the morphology of poly(caprolactone) using pressurised gyration

“…Due to the ribbon-like fibres and products generated by the 15wt%, 20wt% and 25wt% solutions, respectively, the inter-bead distances for these three solutions were not measurable. When the solution's viscosity is very low, surface tension (Table 3) is the main factor that affects fibre morphologies, with higher surface tension giving more beaded or bead on string structures [1,23].…”

Porous Polymeric Bioresorbable Scaffolds for Tissue Engineering

“…The commonly accepted definition of biomaterial was proposed at the Conference of the European Society for Biomaterials (England, 1986): "any substance, other than a drug, or combination of substances, synthetic or natural in origin, which can be used for any period of time, as a whole or as a part of a system which treats, augments, or replaces any tissue, organ, or function of the body" [36].…”

“…The basic requirement of a biomaterial is to be biocompatible, namely "to perform with an appropriate host response in a specific application" [36]. The biomaterial itself, but also additives or degradation products, must not cause harmful reactions in contact with the body.…”