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Elimination of heavy metals from wastewater has been a significant process to improve the aquatic source's quality. Various materials act as very effective adsorbents to remove heavy metals, which cause toxicity to plants and all other living organisms. Thus, the present work focuses on removing heavy metals chromium (Cr) and copper (Cu) ions containing wastewater using biodegradable and cost-effective chitosan-based hydrogel composite. The composite was prepared via chemical cross-linking of radical chitosan with polyacrylamide and N,N'-Methylene bisacrylamide and blended with orange peel. The synthesis of the adsorbent has been confirmed by using Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy - Energy dispersive X-ray analysis (SEM-EDAX) and X-ray diffraction (XRD) studies. The adsorption power of the composite of metal ions at different time, pH, adsorbent dosages, different metal ion concentrations were analyzed by using Atomic Absorption Spectroscopy (AAS). The results concluded that the optimum pH for Cr(VI) and Cu (II) were 4 and 5, contact time: 360 min, adsorbent dosage: 4 g, and initial metal ion concentration: 100 mg/L for each metal ions. The adsorption isotherm models follow the Freundlich model and pseudo-second-order kinetics. From the results, the adsorption capacity was observed to be 80.43% for Cr(VI) and 82.47% for Cu(II) ions, respectively., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The present study focuses on fabrication and characterisation of porous composite scaffold containing hydroxyapatite (HAP), chitosan, and gelatin with an average pore size of 250-1010 nm for improving wound repair and regeneration by Electrospinning method. From the results of X -Ray Diffraction (XRD) study, the peaks correspond to crystallographic structure of HAP powder. The presence of functional group bonds of HAP powder, Chitosan and scaffold was studied using Fourier Transform Infrared Spectroscopy (FTIR). The surface morphology of the scaffold was observed using Scanning Electron Microscope (SEM). The Bioactivity of the Nano composite scaffolds was studied using simulated body fluid solution at 37 ± 1°C. The biodegradability test was studied using Tris-Buffer solution for the prepared nanocomposites [nano Chitosan, nano Chitosan gelatin, Nano based Hydroxyapatite Chitosan gelatin]. The cell migration and potential biocompatibility of nHAP-chitosan-gelatin scaffold was assessed via wound scratch assay and were compared to povedeen as control. Cytocompatibility evaluation for Vero Cells using wound scratch assay showed that the fabricated porous nanocomposite scaffold possess higher cell proliferation and growth than that of povedeen. Thus, the study showed that the developed nanocomposite scaffolds are potential candidates for regenerating damaged cell tissue in wound healing process.

The potential of sodium alginate (AL)/ chitosan (CS)/ carboxymethyl cellulose (CMC) beads as an adsorbent for removing the divalent metal ions such as Cu (II) and Ni (II) ions from aqueous solution was assessed in the current work using a batch adsorption technique. FT-IR and XRD measurements were used to investigate the formation of the ternary beads. The percentage removal of metal ions was investigated in batch mode as a function of metal ion solution pH, initial metal ion concentration, adsorbent dosage, and contact time. The observed outcome shows that the best pH for removing both metal ions was reported to be 5.0. The incorporation of experimental data in theoretical modelling exhibits that the adsorption would be multilayer through pseudo-second order (R² > 0.9) kinetics. The removal efficiency of ternary beads reveals that copper ions (Cmax = 203.69 mg/g) were removed better than nickel ions (Cmax = 194.05 mg/g). [ABSTRACT FROM AUTHOR]

The current work suggests employing an unique Chitosan-g-Maleic anhydride-g-ethylene dimethacrylate copolymer to remove the harmful heavy element copper. By adjusting variables like the concentration of the monomer, the concentration of the initiator, and the temperature during the chain polymerization reaction, the graft copolymer was developed. The copolymer obtained at the optimum condition was picked out to study its adsorption property towards Cu2+ ions. The adsorption factors, such as the amount of adsorbent, contact time, pH, and initial concentration of the metal solution, which affect the adsorption process, were looked at using the batch adsorption mode. Freundlich and Langmuir isotherm models were applied to analyse the equilibrium adsorption. [ABSTRACT FROM AUTHOR]

The preparation and characterisation of a polymeric composite incorporating graphene, hydroxyapatite, and chitosan as an adsorbent to remove chromium (VI) from wastewater. The FTIR and XRD studies supported the composite's production. Analysis of surface morphology and heat stability involved TGA and SEM studies. A batch adsorption was run to determine the efficacy of the adsorbent by varying contact time, adsorbent dose, and pH. The kinetics of the adsorption process were examined using pseudo-first and second order kinetic models after the equilibrium data had been fitted with the Langmuir and Freundlich isotherms. The findings showed that pseudo second order kinetics was utilised for the adsorption of Cr(VI) onto chitosan-grafted graphene/hydroxyapatite (CS-g-Gr/HA) composite. [ABSTRACT FROM AUTHOR]

The Schiff base of carboxymethyl chitosan/p-dimethylaminobenzaldehyde (CMC-SB), as well as its complexes with cobalt (CMC-SB-Co), nickel (CMC-SB-Ni), and zinc (CMC-SB-Zn), were synthesised and studied using FTIR, XRD, TGA, DSC, and SEM. Schiff base metal complex production has been verified by the FTIR and XRD data. According to the thermal studies, the CMC-SB Zinc combination has better thermal stability than other complexes. The material is porous and rough, and the SEM results show that it has several potential uses in the biological field. The zinc complexes have increased activity when it comes to catalysis. It has been determined by the MTT test and ALP activity that the synthesised sample is non-toxic, compatible, and has good antioxidant activity. [ABSTRACT FROM AUTHOR]

Background: Johne's disease (JD) is a chronic, economically important disease of domestic ruminants. Continuous efforts are being made to develop a potent vaccine for JD which confer a longer immunity. The present study was aimed at developing chitosan nanoparticles coupled JD vaccine and assess its efficacy. Methods: Potency of a heat killed, chitosan nanoparticle coupled JD vaccine developed with an Indian isolate of Mycobacterium avium subsp paratuberculosis (MAP) was tested in 107 goats. Pre and post immunization blood samples were collected at different time points and peripheral blood mononuclear cells were used for assessing IFN-γ, IL-2, IL-10 and IL-12 gene expressions. Immunized animals were challenged with a field isolate of MAP and the immune response was assessed. Result: Immunized goats were safe with no untoward reactions. Cytokine gene expression studies indicated a good Th1 response during 3-14 wk post immunization. The initial Th1 response was followed by a good Th2 response with a better IL-10 response than the IFN-γ and IL-2 responses in vaccinated animals at 23 wk PI. Both Th1 and Th2 responses were significantly higher in immunized animals at 23 and 34 weeks post challenge indicating a protective immune response. [ABSTRACT FROM AUTHOR]