Overcoming drug crystallization in electrospun fibers – Elucidating key parameters and developing strategies for drug delivery

Electrospun polycaprolactone nanofibers as a potential oromucosal delivery system for poorly water-soluble drugs

“…The changes in the drug's crystallinity due to the electrospinning of the PCL solution were already reported in previous studies (Kouhi et al, 2013;Seif et al, 2015;Valarezo et al, 2013;Vrbata et al, 2013;Zamani et al, 2010). The group of Vrbata confirmed the changed crystalline structure of naproxen and sumatriptan succinate when incorporated into PCL nanofibers (Vrbata et al, 2013).…”

“…In the DSC curves of all the drug-loaded nanofibers the endothermic peak, which would indicate melting of the drug, is absent. This finding suggests that the ibuprofen and carvedilol were molecularly dispersed in the polymer matrix, indicating the formation of a solid solution (Bodmeier and Chen, 1989;Kouhi et al, 2013;Seif et al, 2015;Vrbata et al, 2013;Zamani et al, 2010) or the drugs were amorphous (Kouhi et al, 2013;Vrbata et al, 2013). However, the glass transition temperatures were not observed for any sample of drug-loaded nanofibers or films in the scope of our study.…”

“…PCL has previously been reported as a main building block of different PCLbased formulations, e.g., micro and nanospheres (Sinha et al, 2004), films, micelles, scaffolds, and fibers (Dash and Konkimalla, 2012;Woodruff and Hutmacher, 2010). It has also been successfully electrospun in previous studies (Canbolat et al, 2014;Fujihara et al, 2005;Karuppuswamy et al, 2015;Kenawy et al, 2009;Kim et al, 2012;Kouhi et al, 2013;Li et al, 2005;LuongVan et al, 2006;Madhaiyan et al, 2013;Reneker et al, 2002;Seif et al, 2015;Shin et al, 2004;Srikar et al, 2007;Valarezo et al, 2013;Vrbata et al, 2013;Yoshimoto et al, 2003;Zamani et al, 2010).…”

“…During the electrospinning of a polymer solution the rapid evaporation of the solvent results in the instant formation of nanofibers and the entrapment of the drug in the polymer matrix or its deposition onto the nanofiber surface (Seif et al, 2015;Yu et al, 2010), resulting in a decreased drug mobility (Yu et al, 2010). The drugs are usually randomly encapsulated within ultrathin and flexible polymer nanofibers with a very high surface area available for contact with the application site.…”

Tracking of crystalline-amorphous transition of carvedilol in rotary spun microfibers and their formulation to orodispersible tablets for in vitro dissolution enhancement

“…It has been pointed out in previous papers that the polarity of the employed solvent mixture and the solubility of the active ingredient, the polymer crystallinity, as well as the chosen process parameters have an impact on the crystallization of the drug in the course of electrospinning [14][15][16]. On the other hand, aging of the polymeric matrix can also result in the alteration of the drug release kinetics; therefore it is essential to obtain structure-related characteristics of the polymer during stability test.…”