Electrospinning of biocompatible polymeric nanofibers functionalized with cyclodextrin inclusion complex

Abstract

Electrospinning is a simple, versatile and cost-effective method to produce nanofibers. Electrospun nanofibers have high surface area to volume ratio and nanoporous structure. Moreover, electrospun nanofibers could be functionalized with additives to extend their application areas. Cyclodextrins (CDs) are cyclic oligosaccharides and have truncated-cone shape structure. Due to their hydrophobic cavity, CDs have ability to form inclusion complex (IC) with a variety of molecule. In our study, we functionalized electrospun nanofibers with CDs and CD-ICs. In the first part, we successfully produced hydroxypropyl cellulose- (HPC), carboxymethyl cellulose- (CMC) and alginate-based nanofibers via electrospinning. Then we functionalized these nanofibers with CDs. The morphological characterizations of nanofibers were performed through scanning electron microscopy (SEM). Here, we have combined the properties of both electrospun nanofibers and CDs, and these nanofibers could be used in drug delivery, wound healing and tissue engineering applications. In the second part, we prepared IC of sulfisoxazole (SFS) (hydrophobic drug) with hydroxypropyl-beta-cyclodextrin (HPβCD) (SFS/HPβCD-IC). Then electrospinning of SFS/HPβCD-IC incorporating hydroxypropyl cellulose (HPC) nanofibers were performed (SFS/HPβCD-IC-HPC-NFs). In the third part of our study, we produced IC of α-tocopherol (α-TC) (antioxidant molecule) with beta-cyclodextrin (β-CD) (α-TC/β-CD-IC); and polycaprolactone (PCL) nanofibers incorporating α-TC/β-CD-IC was obtained via electrospinning (α- TC/β-CD-PCL-NFs). In the fourth part, IC of allyl isothiocyanate (AITC) (antibacterial compound) with β-CD (AITC/β-CD-IC) was produced. The electrospinning of AITC/β-CD-IC incorporating polyvinyl alcohol (PVA) nanofibers was carried out (AITC/β-CD-IC-PVA-NFs). In the fifth part, IC of quercetin (QU) (antioxidant molecule) with β-CD (QU/β-CD-IC) was prepared; and polyacrylic acid (PAA) nanofibers incorporating QU/β-CD-IC was obtained via electrospinning (QU/β-CD-IC-PAA-NFs). The structural and thermal characterizations of SFS/HPβCD-IC-HPC-NFs, α-TC/β-CD-PCL-NFs, AITC/β- CD-IC-PVA-NFs and QU/β-CD-IC-PAA-NFs were carried out by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The amount of released molecules were determined via liquid chromatography-mass spectroscopy (LC-MS) for SFS/HPβCD-IC-HPC-NFs; high performance liquid chromatography (HPLC) for α-TC/β-CD-PCL-NFs and QU/β-CD-IC-PAA-NFs and gas chromatography-mass spectrometry (GC-MS) for AITC/β-CD-IC-PVANFs. The antioxidant activity of α-TC/β-CD-PCL-NFs and QU/β-CD-IC-PAANFs was investigated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Moreover, α-TC/β-CD-PCL-NFs released great proportion of α-TC after exposing UV light. Thus, α-TC/β-CD-PCL-NFs exhibited quite high photostability. The antibacterial activity of AITC/β-CD-IC-PVA-NFs was evaluated by colony counting method against Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus). In brief, we concluded that SFS/HPβCD-ICHPC-NFs, α-TC/β-CD-PCL-NFs, AITC/β-CD-IC-PVA-NFs and QU/β-CD-ICPAA-NFs are promising materials for drug delivery and wound healing applications.