Title: Solution blow spun Poly(lactic acid)/Hydroxypropyl methylcellulose nanofibers with antimicrobial properties Authors
Submitted to: European Polymer Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 5, 2014
Publication Date: February 18, 2014
Citation: Bilbao-Sainz, C., Chiou, B., Valenzuela-Medina, D., Du, W., Gregorski, K.S., Williams, T.G., Wood, D.F., Glenn, G.M., Orts, W.J. 2014. Solution blow spun Poly(lactic acid)/Hydroxypropyl methylcellulose nanofibers with antimicrobial properties. European Polymer Journal. 54:1-10. Interpretive Summary: Solution blow spinning is an alternate technique to electrospinning for producing nano- and microfibers. It offers some advantages over electrospinning, including the elimination of high voltage use, an increase in fiber production rate, and a wider range of materials that can be used as collectors. In this study, poly(lactic acid) fibers containing hydroxypropyl methylcellulose (HPMC) and an antibiotic, tetracycline hydrochloride, were developed for controlled-release applications. Fibers containing HPMC showed improved antimicrobial properties compared to fibers without HPMC. This was due to the antibiotic being more compatible with HPMC and HPMC serving as a carrier for the antibiotic. These results suggested that these fibers can be used for applications such as food packaging, textiles, and filters.
Technical Abstract: Poly(lactic acid) (PLA) nanofibers containing hydroxypropyl methylcellulose (HPMC) and tetracycline hydrochloride (THC) were solution blow spun from two different solvents, chloroform/acetone (CA, 80:20 v/v) and 2,2,2-triflouroethanol (TFE). The diameter distribution, chemical, thermal, thermal stability, water sorption, and antimicrobial properties were examined for the fibers. Fibers spun from CA generally had larger fiber diameters and wider fiber diameter distributions than those spun from TFE. Fourier transform infrared (FTIR) spectroscopy results indicated successful incorporation of HPMC and THC into the fibers. Also, phase separation occurred between PLA and HPMC in the fibers. Fibers containing higher HPMC concentrations showed greater water sorption values, due to HPMC being more hydrophilic than PLA. In addition, fibers containing HPMC had larger inhibitory zones against Escherichia Coli and Listeria monocytogenes than those without HPMC. This was due to THC having better miscibility with HPMC than PLA and HPMC being able to swell and release more THC when in contact with water. Fibers spun from TFE and CA had comparable inhibitory zones, indicating the solvents did not affect antimicrobial properties. All fibers remained effective against bacteria even after six days.