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The main goal of emerging food-packaging technologies is to address environmental issues and minimize their impact, while also guaranteeing food quality and safety for consumers. Bio-based polymers have drawn significant interest as a means to reduce the usage and environmental impact of petroleum-derived polymeric products. Therefore, this current review highlights on the biopolymer blends, various biodegradable bio-nanocomposites materials, and their synthesis and characterization techniques recently used in the smart food packaging industry. In addition, some insights on potential challenges as well as possibilities in future smart food packaging applications are thoroughly explored. Nanocomposite packaging materials derived from biopolymers have the highest potential for use in improved smart food packaging that possesses bio-functional properties. Nanomaterials are utilized for improving the thermal, mechanical, and gas barrier attributes of bio-based polymers while maintaining their biodegradable and non-toxic qualities. The packaging films that were developed exhibited enhanced barrier qualities against carbon dioxide, oxygen, and water vapour. Additionally, they demonstrated better mechanical strength, thermal stability, and antibacterial activity. More research is needed to develop and use smart food packaging materials based on bio-nanocomposites on a worldwide scale, while removing plastic packaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Polymers derived from plant and animal sources are of great interest in wastewater remediation due to their cost-effectiveness and renewable adsorption capabilities, one such polymer is nanocellulose (NC). NC has gained a lot of attention in various research fields due to its abundance in nature, nano-dimension, high surface area, stability and bio-compatibility. As a result, NC has emerged as a great potential adsorbent for the removal of contaminants such as heavy metals, organic dyes, oils, pharmaceutical and etc. in the environmental remediation. This review focuses on the description of the building blocks, structure, properties, isolation and also discusses the potential of nanocellulose based composites materials with reinforcements such as activated carbon, carbon nanotube, graphene oxides, metals, non-metals and ceramics that were effectively used as an adsorbents for diverse organic and inorganic contaminants in water., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Acylated chitosan (Myristoyl and Octanoyl) coated paclitaxel-loaded liposomal formulation was developed with an aim to overcome the cremophor EL related toxicities. They were evaluated for drug entrapment, in vitro drug release, and cytotoxicity and cell uptake behavior using A549 cells. The 99m Tc radio-labeled formulations were also evaluated in vivo in Ehrlich Ascites Tumor (EAT) bearing mice for biodistribution and tumor uptake. The mean particle size of both coated and uncoated liposomal formulations was found to be in the range of 180-200 nm with high drug entrapment efficiency (>90% in case of uncoated liposomes and 80 ± 5% in case of coated liposomes). The uncoated liposomes displayed negative zeta potential (-10.5 ± 4.9 mV) whereas coated liposomes displayed positive zeta potential in the range of +21 to +27 mV. Slower drug release was observed in case of liposomes coated with acylated chitosans as compared to uncoated and native chitosan coated liposomes. All liposomal formulations were found less cytotoxic than paclitaxel injection (Celtax™, Celon Labs, India). In vitro cell uptake and intracellular distribution studies confirmed the cytosolic delivery of uncoated and coated liposomes. The myristoyl chitosan coated liposomal system (LMC) exhibited improved pharmacokinetic, biodistribution and tumor uptake characteristics over other formulations. These obtained results confirmed the potential application of acylated chitosn coated liposomal delivery systems (LMC) in tumor targeting of paclitaxel and other drugs., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A nanoadsorbent was synthesized from kraft lignin derived from paper and pulp black liquor, chitosan, and titania (TiO 2 ) and used to remove Brilliant Black dye (BB) from aqueous solution. Transmission electron microscopy measurements confirmed the material was nanoscale and BET studies showed a pore width of 11.36 nm with a BET surface area (S BET ) of 10.75 m 2 /g. The presence of NH, O and TiO functional groups was confirmed by ATR-FTIR, and thermogravimetric analysis indicated the nanoadsorbent was thermally stable up to 300 °C. Scanning electron microscopy showed that lignin had larger particles with well-defined edges, while the surface morphology of chitosan showed non-uniform, short fibrous microstructures. The diffraction patterns of the nanocomposite showed a polycrystalline anatase phase and selected area electron diffraction analysis showed the nanocomposite has small spots making up a ring, indicating the nanoparticles has a crystalline structure. The effects of contact time, solution pH, adsorbent dosage, and initial dye concentration on the adsorption of BB were investigated. The batch adsorption data obeyed the Freundlich isotherm (r 2  = 0.91), and the monolayer adsorption capacities calculated using the linear Langmuir isotherm was 15.8 mg/g at 25 °C. The adsorption kinetic data were described by the pseudo-second order kinetic model (r 2  = 0.93)., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Mesoporous silica containing nanocomposites of in situ polymerised aniline grafted on guar gum (GG), were synthesised by sol-gel technique. Characterization of samples with respect to SEM, TEM, XRD, XPS, FTIR, BET, UV-vis, and PL illustrated the optically active materials with diverse morphologies. Microscopic analysis rendered transitional changes from smooth GG to coated PANI grafts and dense clusters of polysiloxane nanocomposites. FTIR analysis confirmed the interaction of GG-PANI-Si components. XRD diffractograms illustrate tremendous reduction of dominant amorphous phase of GG by grafted HCl doped PANI depicted by characteristic peaks (centred at 2θ=~25° and 2θ=~20.0°) in the partially crystalline and amorphous GG-g-PANI and GG-g-PANI-Si1 nanocomposites. Phase modification through PANI grafting showed specific surface area of GG-g-PANI (7.6m 2 /g) improving immensely with low polysiloxane contents to ~170.6m 2 /g in GG-g-PANI-Si1 compared to 25.6m 2 /g of GG-g-PANI-Si2. The nanocomposites were thermally stable up to ~240°C, each leaving 69% (GG-g-PANI-Si1) and ~77% (GG-g-PANI-Si2) of inorganic residues. Both showed no thermal dedoping, suggesting the good thermal protection offered by polysiloxane layer., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Lead (Pb) pollution is our water system is a major concern, as this metal is toxic even at low concentration. This study aim to fabricate a bio-nanocomposite (cyclodextrin-polycaprolactone titanium dioxide) that will be used as an adsorbent for the removal of lead in aqueous waste. In this study, titanium dioxide was synthesized via sol-gel technique then incorporated in a polymer blend (CD-PCL) via solution blending method. The resulting bio-nanocomposites were characterized using Scanning Electron Microscopy (SEM), transmission electron microscope (TEM) and Brunauer Emmett and Teller (BET). The effect of how factors such as pH, concentration and adsorbent dose affect the removal efficiency of the bio-nanocomposites were studies. Maximum adsorption of lead obtained was 98% at pH 9.7, 10 ppm with 0.005 g dosage. Kinetic studies and adsorption isotherms were also investigated. The adsorption data fit Langmuir isotherm. Pb (II) obeyed pseudo-second order kinetics., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A thermo-alkalistable and surfactant stable endoglucanase (PHS) gene consisting of 554 amino acids was identified from metagenomic library of Puga hot spring using functional screening. PHS gene was overexpressed and purified to homogeneity using affinity chromatography The purified PHS protein presented a single band of 60kDa on the SDS-PAGE gel and zymogram. The recombinant PHS exhibited activity over a broad range of pH and temperature with optima at pH 8.0 and 65°C, respectively and having optimum stability at 60°C and pH 8.0, respectively. The recombinant PHS showed highest substrate specificity using CMC (218.4U/mg) as compared with Barley β-glucan (89.2U/mg) and Avicel (0.8U/mg). The K m and V max of recombinant PHS for CMC were 3.85mg/ml and 370.37μmolmin -1 mg -1 , respectively. The activity of the recombinant PHS was enhanced by treatment with 10mM non-ionic detergents such as Tween 20, Tween 40, Tween 80, Triton X- 100 and PEG and was inhibited by CTAB, SDS. Its functionality was stable in the presence of Fe 3+ but inhibited by Cu 2+ , Hg 2+ , Mn 2+ and Zn 2+ . These properties make PHS endoglucanase a potential candidate for use in laundry, textile,paper and pulp industries., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This research paper reports the photocatalytic properties of Zn-SiO2-Eu3+ and sodium alginate (Alg) based nanocomposites for the degradation of indigo carmine dye. Initially, Eu3+ doped ZnS-SiO2 nanophorphor was synthesized and after that it was incorporated within the grafted crosslinked polymer matrix of Alg with acrylamide-co-acrylic acid in different concentrations. Synthesized materials were characterized using XRD, Raman spectroscopy, FTIR, SEM/EDX, TEM and UV-vis diffuse reflectance spectroscopy. XRD and TEM analyses confirmed the formation of nanoparticles as well as the uniform distribution of the nanoparticles within the polymer matrix. The UV-vis and UV-vis DRS spectral analysis indicated that Eu3+ doping causes a red-shift in the absorption band, resulting in the reduction in band gaps. The synergic effect of ZnS and Eu3+ in the SiO2 evidenced the photocatalytic performance of the catalyst. Alg-cl-poly(AAM-co-MAA)/ZnS-SiO2-Eu3+ nanocomposites were found to be very effective for the degradation of indigo carmine under visible light. Highest photocatalytic performance (93.4%) was shown by the nanocomposite with the 20% concentration of the nanoparticle after 5h. The photocatalytic activity was mainly attributed to the intense light absorption in the visible region and narrow band gap energy., (Copyright © 2014 Elsevier B.V. All rights reserved.)

This article reports the biosorption potential of Gum ghatti (Gg)-grafted-acrylic acid (AA) polymer and its susceptibility to biodegradation by Bacillus subtilis (BS) in two different liquid media, i.e. phosphate buffered saline (PBS) and mineral salt medium (MSM). The progress of biodegradation was monitored after every 15 days using FT-IR and SEM techniques. The degradation of the polymer was further evidenced by a loss of weight of 23.2% and 27% in BS-MSM and BS-PBS, respectively, after 60 days. The AA-grafted polymer was then utilized for the removal of Pb(II) and Cu(II) from aqueous solution. The adsorption isotherm data were studied using Langmuir, Freundlich, Temkin, Flory-Huggins and Dubinin-Kaganer-Radushkevich isothermal models. High values of correlation coefficients confirmed the applicability of Langmuir isotherm model used to determine the adsorption capacity of the AA-grafted polymer. The maximum adsorption capacity was found to be 84.74 mg/g for Cu(II) and 310.55 mg/g for Pb(II). Kinetic data were evaluated using pseudo first order, pseudo second order, Elovich, intraparticle diffusion and liquid film diffusion models. The experimental kinetic data fitted well with the pseudo second order rate model., (Copyright © 2013. Published by Elsevier B.V.)

This manuscript briefly reviews the extensive research as well as new developments on chitosan based nanomaterials for various applications. Chitosan is a biocompatible and biodegradable polymer having immense structural possibilities for chemical and mechanical modification to generate novel properties and functions in different fields especially in the biomedical field. Over the last era, research in functional biomaterials such as chitosan has led to the development of new drug delivery system and superior regenerative medicine, currently one of the most quickly growing fields in the area of health science. Chitosan is known as a biomaterial due to its biocompatibility, biodegradability, and non-toxic properties. These properties clearly point out that chitosan has greater potential for future development in different fields of science namely drug delivery, gene delivery, cell imaging, sensors and also in the treatment as well as diagnosis of some diseases like cancer. Chitosan based nanomaterials have superior physical and chemical properties such as high surface area, porosity, tensile strength, conductivity, photo-luminescent as well as increased mechanical properties as comparison to pure chitosan. This review highlights the recent research on different aspect of chitosan based nanomaterials, including their preparation and application., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Biodegradable flocculants of Gum ghatti (Gg) with acrylamide (AAm) were prepared through graft co-polymerization technique using potassium persulphate (KPS)-ascorbic acid (ABC) redox pair as initiator and N,N'-methylene-bis-acrylamide (MBA) as a crosslinker. Gg-cl-poly(AAm) was found to exhibit pH and temperature responsive swelling behavior. Maximum flocculation efficiency of Gg-cl-poly(AAm) was observed with 15 mg L(-1) polymer dose in acidic medium at 50°C. Biodegradation studies of Gg and Gg-cl-poly(AAm) were done using composting method. Gg was found to degrade within 20 days, whereas, Gg-cl-poly(AAm) was found to degrade 88.18% within 60 days. Different stages of bio-degradation were characterized through FT-IR and SEM techniques., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The synthesis of chitosan-graft-γ-cyclodextrin (Ch-g-γ-CD) using persulfate/ascorbic acid redox system was done and characterized by FTIR, XRD, TGA and SEM/EDX. The optimum yield of the copolymer was obtained using 16×10(-3) M γ-cyclodextrins (γ-CD), 2.8×10(-2) M ascorbic acid (AA), 1.8×10(-2) M K(2)S(2)O(8) and 0.1g chitosan in 25 mL of 2% aqueous formic acid at 45±0.2°C. The highest percent grafting samples were evaluated for cadmium metal ion (Cd(II)) removal from the aqueous solutions where the sorption capacities were found proportional to the grafting extent. The sorption was pH and concentration dependent where, pH=8.5 was found to be the optimum value. The adsorption data were modeled using Langmuir and Freundlich isotherms. The equilibrium data followed the Langmuir isotherm model with maximum sorption capacity of 833.33 mg/g. The influence of electrolytes, sodium chloride (NaCl) and sodium sulphate (Na(2)SO(4)) on Cd(II) uptake was also studied. Desorption of the cadmium loaded Ch-g-γ-CD was accomplished with 0.01 N H(2)SO(4). The adsorbent exhibited high reusability and could be successfully recycled for nine cycles where in the ninth cycle 27% adsorption was feasible., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Chitosan-N-2-methylhydroxypyridine-6-methylcorboxylate (Ch-PDC) and chitosan-N-2-methylhydroxypyridine-6-methylhydroxy thiocarbohydrazide (Ch-PDC-Th) were synthesized for the first time using chitosan as precursor. Chitosan, Ch-PDC, Ch-PDC-Th were used in the synthesis of gold nanoparticles (AuNP) in aqueous medium. Chitosan and Ch-PDC-Th possess reducing properties which enabled the 'green' synthesis of AuNPs. The stabilization of the AuNPs was as a result of the thiocarbide (SC) and amine (NH(2)) groups in the chitosan matrix. The modified chitosan, its derivatives and the resulting AuNPs were characterized by Fourier transform infrared (FTIR) spectroscopy, Ultraviolet-visible (UV-vis) spectroscopy, Raman scattering measurements, powder X-ray diffraction (PXRD) and thermo gravimetric analysis (TGA). Particle size, morphology, segregation and individuality of the AuNPs were examined by transmission electron microscope (TEM) and energy dispersion spectroscopy (EDS). An average AuNPs size of 20 nm was observed for chitosan and Ch-PDC-Th while Ch-PDC was 50 nm. In comparison, AuNPs resulting from Ch-PDC-Th precursor has the most enhanced Raman and fluorescent intensities and was stable for over 2 months., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Microwave induced copolymerization of beta-cyclodextrin (beta-CD) and chitosan (Ch) resulted in copolymer Ch-g-beta-CD synthesized without any radical initiator or catalyst. Copolymer samples of different performances in terms of Pb(II) binding were synthesized by changing beta-CD concentration at fixed microwave power and exposure time. To understand the advantage of using microwaves in the adsorbent synthesis, the copolymer synthesized using a K(2)S(2)O(8)/ascorbic acid redox pair at identical beta-CD and Chitosan concentrations (% G 103) was also evaluated as Pb(II) sorbent, and the results obtained were compared with that of microwave synthesized copolymer. A representative sample of microwave synthesized adsorbent was characterized using FTIR spectroscopy, X-ray diffraction, TGA, SEM analysis and using this sample adsorption of lead (II) was studied as a function of pH, initial Pb(II) concentration. The adsorption data followed both Freundlich and Langmuir isotherms. On the basis of the Langmuir model, Q(max) was calculated to be 434.78mg/g for microwave synthesized copolymer (Ch-g-beta-CD) in comparison to 294.11mg/g for conventionally synthesized copolymer (Ch-g-beta-CD). In order to investigate dynamic behaviour of Ch-g-beta-CD as an adsorbent, the kinetic data were modelled using pseudo-second-order and second-order. The regeneration experiments revealed that the Ch-g-beta-CD can be successfully reused for seven cycles.