Polymer-free electrospun nanofibers from sulfobutyl ether7-beta-cyclodextrin (SBE7-β-CD) inclusion complex with sulfisoxazole: fast-dissolving and enhanced water-solubility of sulfisoxazole

Abstract

In this study, our aim was to develop solid drug-cyclodextrin inclusion complex system having nanofibrous morphology in order to have fast-dissolving property and enhanced water-solubility of poorly water-soluble drug. Here, we prepared a highly concentrated aqueous solution of inclusion complex between sulfisoxazole and sulfobutyl ether7-beta-cyclodextrin (SBE7-β-CD, Captisol®), and then, without using any polymeric matrix, the electrospinning of sulfisoxazole/SBE7-β-CD-IC nanofibers was performed in order to obtain free-standing and handy nanofibrous web. As a control sample, nanofibers from pure SBE7-β-CD was also electrospun and free-standing nanofibrous web was obtained. The SEM imaging revealed that the bead-free and uniform nanofiber morphology with the average fiber diameter (AFD) of 650 ± 290 nm for sulfisoxazole/SBE7-β-CD-IC NF and 890 ± 415 nm for pure SBE7-β-CD NF was obtained. The inclusion complex formation between sulfisoxazole and SBE7-β-CD in sulfisoxazole/SBE7-β-CD-IC NF sample was confirmed by 1H NMR, TGA, DSC, XRD and FTIR analyses. Due to the combined advantage of cyclodextrin inclusion complexation and high surface area of electrospun nanofibers, fast-dissolving property with enhanced water-solubility was successfully achieved for sulfisoxazole/SBE7-β-CD-IC NF. Our findings suggest that electrospun nanofibers/nanowebs from CD-IC of poorly water-soluble drugs may offer applicable approaches for high water-solubility and fast-dissolving tablet formulations for drug delivery systems.