Antibacterial Cellulose Fibers Spun from Ionic Liquid and Enriched with Plant Essential Oils

Abstract

The COVID-19 outbreak has seen the widespread use of personal protective equipment, especially antibacterial fibers. In this work, ionic liquid (IL) is used as a solvent to fabricate antibacterial fibers combining plant essential oils (PEOs) with cellulose. PEOs are buried in microcapsules first or mixed directly with IL-cellulose spinning dopes to prepare a series of composite fibers. The internal structures, surface and cross morphologies, thermal stability, mechanical properties, antibacterial activity, washing stability, and biocompatibility of these fibers are investigated and analyzed in-depth further. Artemisia microcapsule fiber (AMC-RCF) with a break strength of 30.07 MPa is obtained. Besides, the antibacterial activity rates of AMC-RCF against Escherichia coli and Staphylococcus aureus are 89.8 and 97.8%, and the fibers still have a long-lasting antibacterial effect after 30 standard washes. Furthermore, the antibacterial fibers exhibit excellent biocompatibility. This research provides a green approach for the fabrication of the antibacterial fibers with long-lasting antibacterial activity and good biocompatibility.

Preparation of Antibacterial Biobased Fibers by Triaxial Microfluidic Spinning Technology Using Ionic Liquids as the Solvents

“…Coating antibacterial agents within microcapsules 15 or chemical grafting it to RCF 16 could reduce the loss of antibacterial agents, but these methods are complex and costly, making it a challenge to be implemented in industry. Therefore, it is urgent to propose a new strategy to achieve (a) efficient utilization of antibacterial agents, (b) durable antibacterial ability, and (c) simple preparation processes.…”

“…Our group has successfully screened and prepared antibacterial cellulose fibers by blending natural antibacterial agents into fibers and using ionic liquids (ILs) as the solvents. It was found that the loss rate of the antibacterial agent within the fiber prepared by the blending method was up to 50%, and the antibacterial activity decreased significantly from approximately 90% to about 60% after 30 washing cycles , because the antibacterial agents tend to enter the coagulation bath with the solvents or become suspended in the washing bath during the coagulation and washing processes. Coating antibacterial agents within microcapsules or chemical grafting it to RCF could reduce the loss of antibacterial agents, but these methods are complex and costly, making it a challenge to be implemented in industry.…”

“…It was found that the loss rate of the antibacterial agent within the fiber prepared by the blending method was up to 50%, and the antibacterial activity decreased significantly from approximately 90% to about 60% after 30 washing cycles , because the antibacterial agents tend to enter the coagulation bath with the solvents or become suspended in the washing bath during the coagulation and washing processes. Coating antibacterial agents within microcapsules or chemical grafting it to RCF could reduce the loss of antibacterial agents, but these methods are complex and costly, making it a challenge to be implemented in industry. Therefore, it is urgent to propose a new strategy to achieve (a) efficient utilization of antibacterial agents, (b) durable antibacterial ability, and (c) simple preparation processes.…”

“…By manipulating the flow states of multiple fluids, it is possible to fabricate various types of specialized fibers with distinct compositions and structures. − In this study, antibacterial RCFs with varying antibacterial agent distributions were successfully prepared by triaxial microfluidic spinning technology, and the optimal spinning process was identified. 1-Ethyl-3-methylimidazolium diethyl phosphate ([Emim]­DEP) and 1-ethyl-3-methylimidazolium acetate ([Emim]­Ac), two kinds of ionic liquids (ILs), were used as the solvents, which exhibit excellent solubility for cellulose , and many antibacterial agents such as quercetin, aloe-emodin, and thymol, without destroying their antibacterial activity. , Dimethyl sulfoxide (DMSO) was used as the cosolvent to enhance the solubility of cellulose and quercetin, as well as effectively reduce the viscosity of the IL/DMSO/cellulose spinning dope, facilitating a smooth microfluidic spinning process . As illustrated in Scheme , quercetin/IL/DMSO/cellulose spinning dope was injected into the middle inlet and IL/DMSO/cellulose spinning dopes were injected into the inner and outer inlets of the triaxial microchannel.…”