Synthesis and characterization of hybrid multiwalled carbon nanotube-polycaprolactone-selenium nanoparticles nanofibres and its antibacterial properties

Abstract

Antibacterial materials are particularly important nowadays in many applications such as disinfecting surfaces and maintaining a healthy, clean, and safe environment. This is to prevent any bacterial infection and kill potentially harmful microbes that can cause morbidity and mortality. Hybrid poly-(ε-caprolactone) (PCL) nanofibres are biodegradable antibacterial biomaterials that are essential for preventing and combating dangerous bacterial infections. Hybrid PCL nanofibres were synthesised by incorporating multi-walled carbon nanotubes (MWCNTs) or/and selenium nanoparticles (SeNPs) with PCL nanofibres. Firstly, MWCNTs were purified and functionalised using mild acid, followed by the synthesis of SeNPs by oxidising selenious acid (H2SeO3) with ascorbic acid. The carboxyl group was attached to the MWCNTs surface while trigonal SeNPs were successfully synthesised with a purity of 97.15%. The synthesis of PCL nanofibres with nanoparticles at different concentrations by electrospinning was optimised, having concentrations of 0.08 wt.% and 0.6 wt.% of MWCNTs and SeNPs, respectively. FESEM images showed the formation of aligned fibres with a size of less than 530 nm. The FESEM images confirmed that PCL-MWCNTs-SeNPs nanofibres degraded faster followed by PCL-SeNPs, PCL-MWCNTs, and PCL nanofibres. The presence of nanoparticles enhanced the biodegradation process by the agglomeration of nanofibres before holes appeared, degrading the nanofibres. The inhibition zone for PCL-MWCNTs, PCL-SeNPs, and PCL-MWCNTs-SeNPs nanofibres against Escherichia coli was around 9–13 mm and 10–16 mm for Staphylococcus aureus. The synergistic effects of MWCNTs and SeNPs in PCL-MWCNTs-SeNP nanofibres began degradation in the fourth month and are more effective in inhibiting E. coli and S. aureus. The characteristics of PCL nanofibres are still maintained and capable of decreasing the hydrophobicity and enhancing the biodegradation rate, as well as antibacterial properties of the hybrid PCL nanofibres. From this study, hybrid PCL nanofibres have the potential to be used in broad and various applications, from daily products to specific applications, especially in healthcare and medical applications.