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The antibacterial characteristics of graphene oxide (GO-SB) nano-sheets generated by charring sugarcane bagasse (SB) are described in this study. The antibacterial capability of GO-SB was improved when it was grafted with ethyl cellulose (EC) and polyvinyl alcohol (PVA) to form GO-SB/EC/PVA hydrogels. Characterization of GO-SB nanosheets and GO-SB/EC/PVA hydrogels was accomplished by using FTIR, SEM, XRD, and thermal studies. The antimicrobial activity was carried out against Gram positive bacteria [Micrococcus leutus & Staphylococcus aureus], Gram negative bacteria [Escherichia coli, Pseudomonas aeruginosa] and pathogenic fungal yeast [Candida albicans] applying the disc diffusion method. The disc diffusion method results showed that the improved GO-SB/EC/PVA exhibited a reasonable level of antimicrobial capability against Micrococcus leutus, demonstrating that the antimicrobial improvement of GO-SB was more effective in the GO-SB/EC/PVA hydrogels by increasing the inhibition zone of Gram-positive bacteria, Micrococcus leutus from (13.0 to 16.0 mm)., (© 2024. The Author(s).)

A novel adsorbent was prepared using a backbone comprising chemically hybridized dialdehyde cellulose (DAC) with chitosan via Schiff base reaction, followed by graft copolymerization of acrylic acid. Fourier transform infrared spectroscopy (FTIR) confirmed the hybridization while scanning electron microscopy (SEM) revealed intensive covering of chitosan onto the surface of DAC. At the same time, energy dispersive X-ray (EDX) proved the emergence of nitrogen derived from chitosan. The X-ray diffraction (XRD) indicated that the crystallinity of the backbone and graft copolymer structures was neither affected post the hybridization nor the grafting polymerization. The adsorbent showed high swelling capacity (872%) and highly efficient removal and selectivity of Ni 2+ in the presence of other disturbing ions such as Pb 2+ or Cu 2+ . The kinetic study found that the second-order kinetic model could better describe the adsorption process of (Cu 2+ , Ni 2+ ) on the graft copolymer. In contrast, the first-order kinetic model prevails for the binary mixture (Pb 2+ , Ni 2+ ). Moreover, the correlation coefficient values for the adsorption process of these binary elements using Langmuir and Freundlich isotherms confirmed that the developed grafted DAC/chitosan exhibits a good fit with both isotherm models, which indicates its broadened and complicated structure. Furthermore, the grafted DAC/chitosan exhibited high efficient regeneration and high adsorption capacity for Pb 2+ , Cu 2+ and Ni 2+ ., (© 2023. Springer Nature Switzerland AG.)

This study aimed to prepare antifouling and highly mechanical strengthening membranes for brackish and underground water desalination. It was designed from cellulose acetate (CA) loaded anatase. Anatase was prepared from tetra-iso-propylorthotitanate and carboxymethyl cellulose. Different concentrations of anatase (0.2, 0.3, 0.5, 0.6, 0.7, and 0.8)% were loaded onto CA during the inversion phase preparation of the membranes. The prepared membranes were characterized using Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM & EDX), mechanical properties, swelling ratio, porosity determination, and ion release. The analysis confirmed the formation of anatase on the surface and inside the macro-voids of the membrane. Furthermore, anatase loading improved the CA membrane's mechanical properties and decreased its swelling and porosity rate. Also, CA-loaded anatase membranes displayed a significant antibacterial potential against Gram-positive and Gram-negative bacteria. The results showed that the salt rejection of the CA/anatase films as-prepared varies considerably with the addition of nanomaterial, rising from 46%:92% with the prepared membranes under the 10-bar operation condition and 5 g/L NaCl input concentration. It can be concluded that the prepared CA-loaded anatase membranes have high mechanical properties that are safe, economical, available, and can stop membrane biofouling., (© 2023. Springer Nature Switzerland AG.)

Synthesis of new compounds that have biological activity is an indispensible issue in order to deal with the drug resistant bacteria. This wok reports preparation of a novel composite based on substituted pyrido[2,1-b][1,3,4] oxadiazine-dialdehyde chitosan (PODACs) conjugate. Firstly, a novel approach of synthesizing of a new substituted pyrido[2,1-b][1,3,4]oxadiazine-7-carboxylic acid (PO) is reported through reacting(Z)-N'-(1-(3-aminophenyl)ethylidene)-2-cyanoacetohydrazide with (Z)-ethyl 2-cyano-3-(pyridin-3-yl)acrylate. Then Dialdehyde chitosan (DACs) has prepared via periodat oxidation of chitosan (Cs). The synthesized compounds have studied via various spectroscopic instruments to validate their chemical structure such as nuclear magnetic resonance 1 H NMR, 13  C NMR, fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM). The substituted pyrido [2,1-b][1,3,4]oxadiazine and the composite were evaluated for antimicrobial activity against pathogenic bacteria and unicellular fungi. The results revealed that, the composite exhibited promising antimicrobial activity against E. coli, S. aureus, B. subtilis and C. albicans where inhibition zones were 19, 18, 36 and 20 mm respectively. Furthermore, the substituted pyrido [2,1-b][1,3,4]oxadiazine and the composite were evaluated for cytotoxic activity against MCF-7 human breast cancer cell line as well as vero normal cell line. Results illustrated the prepared composite has anticancer activity against MCF7 where IC 50 was 238 µg/ml., (© 2023. The Author(s).)

A novel adsorbent from cationic chitosan derivative and anionic silica precursor was fabricated to remove methylene blue (MB). The hybrid material was prepared from N-guanidinium chitosan acetate (GChi) and carboxyethylsilanetriol sodium salt by a simple ionic interaction followed by sol-gel approach. Multiple characterization methods were used to analyze the morphology and the structure of the well-prepared functionalized material. Batch experiments were conducted to optimize the various operational parameters. The Langmuir isotherm was used to fit the data, and it predicted monolayer adsorption with a maximum capacity of 334 mg g -1 . A pseudo-second-order equation fit the adsorption process well. Chitosan/silica hybrids containing carboxylic groups are efficient and cost-effective adsorbents for cationic dyes adsorption from aqueous solutions., (© 2023. The Author(s).)

In this study, we have used hydroxyethyl cellulose (HEC) to prepare antimicrobial films for multipurpose applications. Using HEC gives mangiferin powder (M) mechanical properties, while mangiferin powder gives HEC antimicrobial activities. Various concentrations of M (2.5, 5 and 10% wt/vol) were added to HEC to enhance the antimicrobial ability of HEC/M films. The results showed that 10% (wt/vol) was the optimum concentration to accomplish the antimicrobial activity. Various analyses were performed to study the prepared films' physical, chemical, mechanical, and antimicrobial properties., (© 2022. The Author(s).)