Removal of retained electrospinning solvent prolongs drug release from electrospun PLLA fibers

Abstract

A major challenge in developing drug-releasing electrospun nanofibers is obtaining long-term drug release over many weeks with no burst release of drug. Here, we present new methods capable of prolonging the diffusive release of small molecule drugs from electrospun poly-L-lactic acid (PLLA) nanofibers. The methods focus on removal of retained electrospinning solvent through fiber heating, maintaining fibers in a laboratory setting, or a combination of these methods. These post-fabrication methods altered the release characteristics of a model small molecule drug, 6-aminonicotinamide (6AN), from PLLA fibers. Specifically, untreated fibers released 6AN over 9 days, and fibers that underwent a combined treatment of maintenance in a laboratory setting and heating released 6AN over 44 days. The unique and simple method presented here prolongs diffusive release of a small molecule drug from electrospun fibers and has potential to assist in lengthening small molecule drug release from a variety of polymeric nanomaterials.

Electrospun Bioresorbable Membrane Eluting Chlorhexidine for Dental Implants

“…HFIP is progressively removed from PLC fibers until complete evaporation, which is not the case for PGA electrospun fibers, where remaining solvent was still detected after 14 days [19]. Moreover, PCL has no significant interaction with HFIP (2,3), whereas PLLA has an affinity [20]. It was suggested that solvent retention can be linked to polymer glass transition temperature (T g ): polymers with T g above room temperature could retain solvent because solvent diffusion out of the fibers during the electrospinning is limited by the decrease in polymer chain mobility.…”

Electrospun Functional Materials toward Food Packaging Applications: A Review

“…As an effective strategy, thermal treatments could promote the volatilization of residual solvent. D'Amato et al [120] have developed a new method for removing…”

“…As an effective strategy, thermal treatments could promote the volatilization of residual solvent. D'Amato et al [120] have developed a new method for removing residual solvents to prolong the release time of small molecules in electrospun fibers (Figure 9). Firstly, degradable poly(L-lactic acid) (PLLA) composite nanofibers containing hydrophobic drug 6-aminonicotinamide (6AN) were prepared by using electrospinning technology.…”

Protein encapsulation by electrospinning and electrospraying

“…The generation of particles or fibres by EHD techniques has been used to microencapsulate small molecules [59][60][61][62], DNA [60,63,64], proteins [65,66], and even cells [67][68][69] for therapeutic delivery. Electrospinning produces fibres with high interconnected porosity and adjustable pore size, surface functionalisation potential, and structural similarity to the extracellular matrix (ECM), highlighting its applicability in drug delivery, particularly in tissue regeneration [24].…”