Creating hybrid materials with multifunctionality and robust mechanical stability from natural resources is a challenging proposition in materials science. Here, we report the scalable synthesis of ...hybrid collagen scaffolds using collagen extracted from leather industry wastes and sago starch derived from agro-industry. The hybrid scaffolds were incorporated with TiO
nanoparticles and cross-linked with oxidized sago starch. The biocompatibility, thermal stability and antimicrobial property of hybrid scaffold enabled its application in burn wound healing demonstrated through albino rat models. The highly porous hybrid scaffolds are shown to be super-compressible, which is typically forbidden in materials of biological origin. We demonstrate that the hybrid scaffolds concurrently display both adsorption and absorption behavior in the removal of oil and dye molecules, respectively from contaminated water. This study paves the way for the development of novel multifunctional and shape recoverable hybrid materials specifically from renewable resources.
Severe water deficit and highly polluting effluent generation from leather industries have constantly been pressurizing the tanners to adopt cleaner leather processing systems. The present study aims ...to minimize the use of water by substituting it with non-aqueous green solvents and also to enhance the enzyme action in alpha-amylase based fiber opening process. The activity of alpha-amylase in select non-aqueous green solvents namely, heptane, polyethylene glycol 200 and propylene glycol is considerably higher by 62, 38 and 31% than in water, respectively. Comparable results are obtained for the catalytic efficiency of alpha-amylase and hence it is further validated in collagen fiber opening trials as well. Scanning electron micrographs, histological images and proteoglycan estimation supported the above findings at 1% alpha-amylase dosage. The final quality of the experimental leathers in terms of physical and bulk properties is comparable to that of control leathers. Recycling studies indicate that it is possible to replace water with green solvents for enzymatic fiber opening with the feasibility to recover more than 85% solvent-enzyme mixture and reuse without any additional alpha-amylase usage. Reduction in pollution load coupled with the efficient catalytic action of enzyme in non-aqueous media favors the present protocol for industrial applications.
A stable magnetic nanocomposite of collagen and superparamagnetic iron oxide nanoparticles (SPIONs) is prepared by a simple process utilizing protein wastes from leather industry. Molecular ...interaction between helical collagen fibers and spherical SPIONs is proven through calorimetric, microscopic and spectroscopic techniques. This nanocomposite exhibited selective oil absorption and magnetic tracking ability, allowing it to be used in oil removal applications. The environmental sustainability of the oil adsorbed nanobiocomposite is also demonstrated here through its conversion into a bi-functional graphitic nanocarbon material via heat treatment. The approach highlights new avenues for converting bio-wastes into useful nanomaterials in scalable and inexpensive ways.
Graphene is an intriguing two-dimensional material, which could be modified for achieving tunable properties with many applications. Photoluminescence of graphene due to plasmonic emission is ...well-known, however, attempts to develop strong luminescent graphene have been difficult. Synthesis of a graphene-based material with a dual optical functionality, namely quenching the fluorescence of organic dyes while maintaining its own self-luminescence, is an interesting and challenging proposition. Here, we demonstrate this optical bifunctionality in a lattice-modified luminescent graphene, where europium(III) cations are complexed with graphene through oxygen functionalities. After excitation at 314 nm, a hypersensitive red emission is observed at 614 and 618 nm showing the complexation of europium(III) with graphene. We demonstrate dual functionality of this graphene by the quenching of luminescence of Rhodamine-B while displaying its own hypersensitive red emission. The decay lifetime observed through the time-resolved spectroscopy confirms its potential for applications in biosensing as well as optoelectronics.
In response to the challenges posed by current postharvest preservation methods, this study focuses on the development and characterization of a ginger starch-waste feather keratin (GS-FK) composite ...functionalized with chia oil (CO). Composite films functionalized with 0.5 (GS-FK-CO0.5), 1.0 (GS-FK-CO1.0), and 1.5 (GS-FK-CO1.5) mL of chia oil were fabricated and characterized using standard analytical techniques. GS-FK-CO films in comparison to GS-FK showed increases in thickness and tensile strength, as well as reductions in moisture content, transparency, water solubility, WVP, and elongation at break. GS-FK-CO films demonstrated superior thermal stability and were evaluated for their efficacy in the post-harvest management of tomato fruits. Following coating and storage at 25 ± 2 °C for 21 days, the GS-FK-CO coated tomato fruits exhibited significantly (p > 0.05) lower weight loss, pH, brix value, and ripening index compared to the uncoated control. GS-FK-CO coated fruits in comparison to control displayed elevated levels of titratable acidity, ascorbic acid, and total phenolic acid, along with suppressed activities of polyphenol oxidase, pectin methyl esterase, and polygalacturonase. This study underscores the potential of the chia oil functionalized GS-FK biocomposite as a promising packaging alternative for extended shelf life and enhanced preservation of tomato fruits.
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We report the synthesis of an electrically conductive and magnetically active hybrid biocomposite comprising collagen and polyaniline (PAni) as the matrix and iron oxide nanoparticles (IONPs) as the ...filler through an in situ polymerization technique. Here, the matrix biopolymer, collagen, was extracted from trimmed wastes of animal hides generated from the leather industry. The as-synthesized C/PAni/IONP hybrid biocomposite powder possesses excellent electrical conductivity, thermal stability, and saturation magnetization, thereby providing scope for a wide range of applications. We show that the bifunctional composite has an ability to conduct electrons using a light emitting diode and battery setup, degrade dye under sunlight owing to its inherent photocatalytic activity, and absorb oil from oil–water mixtures with easier collection under magnetic tracking. We also demonstrate that the composite has remarkable electromagnetic interference shielding in the X-band frequency range. The results suggest that biowastes can be converted into useful high-value hybrid materials for applications in catalysis, biological, electronic, and environmental fields, thereby presenting a scalable and sustainable approach.
Management of burn wounds with diabetes and microbial infection is challenging in tissue engineering. The delayed wound healing further leads to scar formation in severe burn injury. Herein, a ...silver‐catechin nanocomposite tethered collagen scaffold with angiogenic and antibacterial properties is developed to enable scarless healing in chronic wounds infected with Pseudomonas aeruginosa under diabetic conditions. Histological observations of the granulation tissues collected from an experimental rat model show characteristic structural organizations similar to normal skin, whereas the open wound and pristine collagen scaffold treated animals display elevated dermis with thick epidermal layer and lack of appendages. Epidermal thickness of the hybrid scaffold treated diabetic animals is lowered to 33 ± 2 µm compared to 90 ± 2 µm for pristine collagen scaffold treated groups. Further, the scar elevation index of 1.3 ± 0.1 estimated for the bioengineered scaffold treated diabetic animals is closer to the normal skin. Immunohistochemical analyses provide compelling evidence for the enhanced angiogenesis as well as downregulated transforming growth factor‐ β1 (TGF‐β1) and upregulated TGF‐β3 expressions in the hybrid scaffold treated animal groups. The insights from this study endorse the bioengineered collagen scaffolds for applications in tissue regeneration without scar in chronic burn wounds.
Collagen based bioengineered scaffolds loaded with silver‐catechin nanocomposite elicit a significant increase in the angiogenesis and transforming growth factor‐β3 (TGF‐β3) expression and decrease in the TGF‐β1 expression. The scaffolds can heal infected burn wounds with low scarring surprisingly in type‐I diabetic animals and lead to a systematic skin reconstruction thereby demonstrating potential for application in chronic wound management.
Tissue engineering (TE) is a promising approach for repairing diseased and damaged bone tissue. Injectable hydrogel based strategies offer a wide range of applications in rapid recovery of bone ...defects by acting as filler materials and depots for delivering various bioactive molecules and averting the need for surgical intervention. Chitosan (CS), a natural polysaccharide, forms a thermosensitive injectable hydrogel through the addition of beta-glycerophosphate (β-GP). This hybrid hydrogel possesses numerous advantages namely mimicking native extracellular matrix (ECM) and providing an amenable microenvironment for cell growth. In this review, a brief insight into the gelation mechanism of CS/GP hydrogels, modifications, bioactive additives and their applications in treating bone defects are presented.
•Chitosan-β-GP hydrogel system is injectable and with gelation at 37 °C.•Chitosan-β-GP hydrogels are widely explored for release of bioactive molecules.•Hybrid or modified form possesses enhanced bioactive and mechanical properties.
Leather processing has emerged as an important economic activity in several developing countries. Awareness of environmental problems has increased considerably and during recent years protecting ...environment has become a global issue. Currently the leather processing industry is going through a phase change due to global environmental regulations. The article summarizes the current leather processing methods with their rationale and environmental problems. It has been revealed that pretanning and tanning processes contribute 80-90% of the total pollution load (BOD, COD, TS, TDS, Cr, S
2−
, sludge, etc.). Further, toxic gases like ammonia and hydrogen sulfide are also emitted. Volatile organic compounds, heavy metals, and carcinogenic arylamines from posttanning and finishing operations are also creating severe concern. Apart from this, a great deal of solid wastes like lime sludge from tannery and chrome sludge from effluent treatment plants are being generated. Advanced processing techniques as well as effluent treatment strategies for combating environmental and human health risks are reviewed in detail. The leather processing industry in various countries, however, is facing a serious challenge from the public and government. This is in spite of the implementation of several advanced processing techniques and treatment systems. Hence, there is a need to revamp leather processing methods anew for the sustainability of leather industry. Some of the novel concepts in leather processing are briefly mentioned and discussed.
•Natural dye extracted from sawdust of Pterocarpus indicus Willd. using ultrasound.•Dyeing and mordanting parameters were optimized.•Pretreatment of cotton and silk improved colour depth, fastness ...and UV protection.•Timber industry waste can be upcycled as a resource for natural dye.
Exploitation of synthetic dyes in a variety of manufacturing sectors including textiles poses serious problems to the environment. Natural dyes are becoming vital alternatives to toxic synthetic dyes, however, with limitations such as availability and process standardization. Herein, we explore the dyeing potential of a sawdust, Pterocarpus indicus Willd., which is widely available as a waste from timber industry in South Asia and other parts of the world. Ultrasound assisted extraction method was carried out to extract natural dye from the sawdust. The extract was used to dye cotton and silk fabrics using various metallic and natural mordants such as alum, stannous chloride, copper sulphate, gallnut, pomegranate rind and gooseberry and the process was optimized. The effect of different pretreatments such as chitosan and myrobalan on dyeing fabrics was also studied. Colour properties of the naturally dyed fabrics such as colour strength, colour co-ordinates and various fastness were assessed. The natural mordants such as gallnut, pomegranate rind and gooseberry provided comparable fastness property to metallic mordants, thereby suggesting the use of the extracted dye with natural mordants for exclusive eco-friendly dyeing. We also demonstrate that chitosan and myrobalan pretreatments significantly enhance the colour strength, colour fastness and UV protection properties of naturally colored cotton and silk fabrics. Overall, the results suggest copper sulphate mordanting with chitosan pretreatment and stannous chloride mordanting with myrobalan pretreatment as the best combination for cotton and silk fabrics, respectively considering the color fastness and UV protection properties. The results provide ample scope for the upcycling of timber industry waste into a natural dye for eco-friendly coloration of fabrics.
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