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In this study, carbon nanofibers (CNFs) assisted chitosan (Cs) was utilized to surface modification of poly(ether sulphone) (PES) nanofiltration membranes. The effect of CNFs-co-Cs nanocomposite layer on physical/chemical properties and separation performance of prepared membranes was investigated. The ability of membranes in heavy metal ions removal from water was studied. Scanning electron microscopy (SEM), Scanning optical microscopy (SOM), Fourier transform infrared spectroscopy (FTIR) and 3D surface images were employed for the membranes characterization. Moreover membrane porosity, mean pore size, water content, water contact angle, flux, salt rejection and tensile strength of fabricated membranes measured. The FTIR analysis verified formation of CNFs-co-Cs layer on the membrane surface. SOM images revealed relatively uniform surface for the prepared membrane. Introducing of CNFs-co-Cs on the PES substrate led to decline of water contact angle from 62.66° to 43.86° sharply. Modified membranes showed higher porosity and water content than virgin PES membrane. The Na 2 SO 4 rejection was measured >66% for PES membrane while it was >82% for PES/CNFs-co-Cs membrane containing of 0.5 wt% CNFs. Pure water flux also enhanced from 4.25 (L/m2.h) for virgin PES membrane up to 13.58 (L/m2.h) for the surface modified membranes. Mechanical tensile strength was also increased considerably for the PES/CNFs-co-Cs membrane containing of 0.5 wt% CNFs that were 3.5 times more than the tensile strength for PES membrane. The Cu, Cr and Pb rejections measured 97.86%, 98.40% and 96.54% for the PES/CNFs-co-Cs membrane with 0.5 wt % CNFs while they were 45.3%, 48.46% and 38.02 for PES substrate respectively. [Display omitted] • PES/CNFs-co-Cs nanofiltration membrane fabricated through intra-networking. • PWF measured 4.25 and 13.58 (L/m 2 h) for PES and [PES/CNFs-co-Cs] membranes. • Na 2 SO4 rejection was >66% and >88% for virgin and surface modified membranes. • [PES/CNFs-co-Cs] membrane showed high ability in Cu, Cr, Pb removal from water. • Outstanding tensile strength obtained for CNFs-co-Cs coated PES based NF membrane. [ABSTRACT FROM AUTHOR]

• Bacterial infections in serious burns have been a constant threat to human health throughout history. • Chitosan has significant antibacterial activity against a broad spectrum of bacteria. • Chitosan nanoparticles could be used as drug carriers and gene carrier to enhance their transfer efficiency in the cells. • Chitosan-based nanomaterials could be used against bacterial infections. Chitosan nanomaterials have become a hot topic in biomedicine due to exerting antimicrobial effects with interestingly high levels of biodegradability and biocompatibility without causing toxicity. Regarded as a potential means of wound dressing with antimicrobial activity, chitosan exhibits higher efficiency when it is functionally modified with other natural compounds, metallic antimicrobial particles and antibiotics. Mechanistically, the antibacterial effect of chitosan is mostly, associated with the death-proceeding leakage of intracellular content, induced by malfunction and altered permeability of the negatively charged cell membrane, on which chitosan is adsorbed. Moreover, chitosan nanoparticles (NPs) are endowed with favorable features of NPs (i.e., large surface-to-volume ratio, high functionalization possibilities and a greater capacity for drug loading), as well as that of their chitosan base, thereby possessing strengthened antibacterial potential. In addition, polycations target negatively charged bacterial membranes, so bacteria cells are more strongly affected by polycationic chitosan NPs than pure chitosan. [ABSTRACT FROM AUTHOR]