Preliminary studies of electrospun guar gum scaffolds for controlled drug delivery

PABLO R. CORTEZ TORNELLO; GERMÁN A. ISLAN; ARUP MUKHERJEE; GUSTAVO A ABRAHAM; GUILLERMO R. CASTRO

La Plata

Workshop; International Workshop on Drug Design and Neglected Tropical Diseases 2016; 2016

Faculty of Exact Sciences

Biopolymer-based nanofibrous scaffolds are being studied because its potential for applications in the medical and pharmaceutical fields. Biopolymers have not only the advantage of being renewable resources, biocompatible and biomimetic compared with synthetic polymers, but also intrinsically exhibit antibacterial activity and biodegradability. Guar gum (GG), a biopolymer obtained from the seeds of Cyamopsis tetragonalobus, is a chain of b-D-mannose units interposed with a-D-galactose moiety. GG is used in pharmaceuticals application for transdermal, intestinal or colonic drug delivery. GG molecules can entrap a large amount of water and coherent structural changes are apparent in GG interactions with water. Moreover, GG backbone is resistant to aerobic hydrolysis and only hydrolyzes partially in anaerobic intestinal or colonic microflora.Electrospinning provides a versatile technology to produce three-dimensional nanofibrous networks with high surface-to-volume ratio and interconnected porosity. In this work, GG nanofibrous scaffolds were obtained by electrospinning technique from polymer aqueous solutions (1.5 % w/v) with different amounts of aqueous solution of trisodium trimetaphosphate (STMP) 30 % w/v (5, 8 and 10 % v/v respectively). STMP was used as crosslinker, reducing the swelling. GG scaffolds were characterized in terms of fiber diameter (as measured by scanning electron microscopy - SEM), thermal properties (differential scanning calorimetry - DSC), swelling degree in sodium chloride solutions, and surface composition (Fourier transform infrared spectroscopy - FTIR).Nonwoven nanofibrous scaffolds were formed by uniform bead-free fibers with mean diameters of 56 ± 12 nm. The thermal results showed that the crosslinked GG scaffolds present higher glass transition temperature and gelatinization enthalpy, probably due to the higher crosslinking. Crosslinking decreases swelling degree (buffer intake) of GG, and then drug release from drug-loaded matrices could be controlled by increasing STMP concentration.