Comprehensive review on collagen extraction from food by-products and waste as a value-added material.

The consumption of animal products has witnessed a significant increase over the years, leading to a growing need for industries to adopt strict waste control measures to mitigate environmental impacts. The disposal of animal waste in landfill can result in diverse and potentially hazardous decomposition by-products. Animal by-products, derived from meat, poultry, seafood and fish industries, offer a substantial raw material source for collagen and gelatin production due to their high protein content. Collagen, being a major protein component of animal tissues, represents an abundant resource that finds application in various chemical and material industries. The demand for collagen-based products continues to grow, yet the availability of primary material remains limited and insufficient to meet projected needs. Consequently, repurposing waste materials that contain collagen provides an opportunity to meet this need while at the same time minimizing the amount of waste that is dumped. This review examines the potential to extract value from the collagen content present in animal-derived waste and by-products. It provides a systematic evaluation of different species groups and discusses various approaches for processing and fabricating repurposed collagen. This review specifically focuses on collagen-based research, encompassing an examination of its physical and chemical properties, as well as the potential for chemical modifications. We have detailed how the research and knowledge built on collagen structure and function will drive the new initiatives that will lead to the development of new products and opportunities in the future. Additionally, it highlights emerging approaches for extracting high-quality protein from waste and discusses efforts to fabricate collagen-based materials leading to the development of new and original products within the chemical, biomedical and physical science-based industries.

Lutein, a carotenoid found in numerous plants and the human eye, demonstrates the capacity to bundle collagen fibrils.

Collagen fibrils serve as the building blocks of the extracellular matrix, providing a resilient and structural framework for tissues. However, the bundling of collagen fibrils is of paramount importance in maintaining the structural integrity and functionality of various tissues in the human body. In this scenario, there is limited exploration of molecules that promote the bundling of collagen fibrils. Investigating the interactions of well-known carotenoids, commonly associated with ocular health, particularly in the retina, with collagen presents a novel and significant area of study. Here, we studied the influence of lutein, a well-known carotenoid present in many plant tissues and has several biological properties, on the structure, thermal stability, self-assembly, and fibrillation of collagen. Fibrillation kinetics and electron microscopic analyses indicated that lutein did not interfere with fibrillation process of collagen, whereas it enhances the lateral fusion of collagen fibrils leading to the formation of compact bundles of thick fibrils under physiological conditions. The hydrophobic and hydrogen bonding interactions between lutein and collagen fibrils are most likely the cause of the bundling of the fibrils. This study establishes the first investigation of collagen-carotenoid interactions, showcasing the unique property of lutein in bundling collagen fibrils, which may find potential application in tissue engineering.

Multifunctional embelin- poly (3-hydroxybutyric acid) and sodium alginate-based core-shell electrospun nanofibrous mat for wound healing applications.

In this study, coaxial electrospinning is employed to make core-shell fibers, which represents a major advance in biomaterial innovation. Fibers that combine a protective shell and a therapeutic agent-loaded core, herald a revolutionary era in tissue engineering and wound care. Besides supporting cell growth, these fibers also preserve sterility, which makes them ideal for advanced wound dressings. We used embelin as the basis for this study because of its natural antibacterial properties. Its effectiveness in inhibiting the growth of bacteria made it the ideal candidate for our research. We have synthesized core-shell nanofibers that contain Sodium Alginate (SAL) in a Poly (ethylene oxide) (PEO) shell and Embelin in a Poly (3-hydroxybutyric acid) (PHB) core, which exhibit the homogeneity and flawless structure required for biomedical applications. When using SAL-PEO and EMB-PHB solutions dissolved in 1,1,1,3,3,3 hexafluoro-2-propanol (HFIP), high consistency in results can be achieved. A biocompatibility study was conducted using NIH-3T3 fibroblasts, which demonstrated remarkable adhesion and proliferation, with over 95 % growth supporting both PHB + SAL-PEO and EMB-PHB + SAL-PEO fibers. In addition, the scaffold loaded with Embelin shows strong antibacterial activity and cytocompatibility. The combined activity demonstrates the potential of EMB-PHB + SAL-PEO fibers in wound healing, where tissue regeneration and preservation of sterility are crucial. The optimized concentration of Embelin within these scaffolds demonstrates robust antibacterial efficacy while exhibiting minimal toxicity, thus positioning them as highly promising candidates for a wide range of biological applications, including wound healing.

Development of masked silica tanning system for sustainable leather production.

Amid mounting pressure on the long-term recyclability of chromium in tanned leather and the associated environmental hazards, the quest for an alternative, cleaner tanning system has gained tremendous momentum. In this context, our study explores the remarkable potential of silicates as a versatile platform for skin/hide tanning, circumventing the inherent risks and ecological threats posed by chromium exposure and leaching. We present an alternative approach of using a silica-based tanning system, employing a Taguchi model, to optimize a masked silica (MaSil) tanning product/process for achieving effective collagen stabilization. Our results demonstrate the significant advancements made in hydrothermal denaturation temperature, reaching an impressive 79 °C through precise Taguchi parameters-5% SiO2, masked with 0.3 mole of citrate salt, and a tanning process fixation pH of 4.5. Notably, the mechanical strength analysis reveals compliance with the stringent upper leather recommendation standards, validating the practicality and quality of MaSil crust leather. Moreover, our research highlights the unprecedented environmental benefits of the first reported application of Taguchi's approach to the MaSil tanning system. The developed tanning system remarkably reduces total dissolved solids (TDS), biological oxygen demand (BOD), chemical oxygen demand (COD), and overall water load by 68.4%, 25.4%, 59.5%, and 33.7%, respectively, heralding a promising era of water and environmental sustainability in the leather sector. This study holds the potential to transform leather production, wherein the envisioned future on the use of the Taguchi model and optimized MaSil tanning system could find a place in shaping a cleaner, greener, and more sustainable leather industry.

3D-Printed Collagen-Nanocellulose Hybrid Bioscaffolds with Tailored Properties for Tissue Engineering Applications.

Hybrid collagen (Coll) bioscaffolds have emerged as a promising solution for tissue engineering (TE) and regenerative medicine. These innovative bioscaffolds combine the beneficial properties of Coll, an important structural protein of the extracellular matrix, with various other biomaterials to create platforms for long-term cell growth and tissue formation. The integration or cross-linking of Coll with other biomaterials increases mechanical strength and stability and introduces tailored biochemical and physical factors that mimic the natural tissue microenvironment. This work reports on the fabrication of chemically cross-linked hybrid bioscaffolds with enhanced properties from the combination of Coll, nanofibrillated cellulose (NFC), carboxymethylcellulose (CMC), and citric acid (CA). The bioscaffolds were prepared by 3D printing ink containing Coll-NFC-CMC-CA followed by freeze-drying, dehydrothermal treatment, and neutralization. Cross-linking through the formation of ester bonds between the polymers and CA in the bioscaffolds was achieved by exposing the bioscaffolds to elevated temperatures in the dry state. The morphology, pores/porosity, chemical composition, structure, thermal behavior, swelling, degradation, and mechanical properties of the bioscaffolds in the dry and wet states were investigated as a function of Coll concentration. The bioscaffolds showed no cytotoxicity to MG-63 human bone osteosarcoma cells as tested by different assays measuring different end points. Overall, the presented hybrid Coll bioscaffolds offer a unique combination of biocompatibility, stability, and structural support, making them valuable tools for TE.

Investigation on Centrifugally Spun Fibrous PCL/3-Methyl Mannoside Mats for Wound Healing Application.

Fibrous structures, in general, have splendid advantages in different forms of micro- and nanomembranes in various fields, including tissue engineering, filtration, clothing, energy storage, etc. In the present work, we develop a fibrous mat by blending the bioactive extract of Cassia auriculata (CA) with polycaprolactone (PCL) using the centrifugal spinning (c-spinning) technique for tissue-engineered implantable material and wound dressing applications. The fibrous mats were developed at a centrifugal speed of 3500 rpm. The PCL concentration for centrifugal spinning with CA extract was optimized at 15% w/v of PCL to achieve better fiber formation. Increasing the extract concentration by more than 2% resulted in crimping of fibers with irregular morphology. The development of fibrous mats using a dual solvent combination resulted in fine pores on the fiber structure. Scanning electron microscope (SEM) images showed that the surface morphology of the fibers in the produced fiber mats (PCL and PCL-CA) was highly porous. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the CA extract contained 3-methyl mannoside as the predominant component. The in vitro cell line studies using NIH3T3 fibroblasts demonstrated that the CA-PCL nanofiber mat was highly biocompatible, supporting cell proliferation. Hence, we conclude that the c-spun, CA-incorporating nanofiber mat can be employed as a tissue-engineered construct for wound healing applications.

Influence of preparation techniques of cellulose II nanocrystals as reinforcement for tannery solid waste-based gelatin composite films.

Tannery waste-based gelatin composite film reinforced with cellulose II nanocrystal (CNC II) extracted from wet wipes using three different hydrolysis techniques is explored for its functional properties and possible utilization as a biodegradable packaging material. CNC II isolated using hydrogen peroxide (PCNC), citric acid (CCNC), and hydrochloric acid (HCNC) differed in morphological and crystalline character as investigated using DLS, FE-SEM, FTIR, and XRD analysis. The crystallinity of PCNC, CCNC, and HCNC was found to be 81.1%, 75.4%, and 86.1%, respectively. The highly crystalline CNC II (PCNC) incorporation improved mechanical stiffness of rawhide trimming waste-based gelatin films by 50% compared to control gelatin film. Maximum thermal decomposition with Tmax of 329 °C was obtained for gelatin films with PCNC nano-reinforcement. Films with CNC II were structurally stable and sufficiently antibacterial against Gram-positive S. aureus microbial strain. Strong interfacial non-covalent and hydrogen bonding interactions between gelatin and cellulose II nanocrystal have likely enhanced the properties of the composite films. Incorporation of CNC II reduced the surface wettability of the films and nanocomposites absorbed UV radiation as evidenced by transmittance value T280 of 0.19%. Nanocomposite films degraded up to 79.9% of initial mass within 7 days of soil burial. Furthermore, based on the optimized system, single-use packaging application of eggplant seeds has been demonstrated.

A cyclodextrin-based macrocyclic oligosaccharide cavitand with a dual functionality limits the collagen fibrillogenesis: A possible carbohydrate-based therapeutic molecule for fibrotic diseases.

ß-Cyclodextrin (ß-CD), a macrocyclic oligosaccharide cavitand, is a well-known candidate for drug delivery and formulation. In this study, we extended the application of ß-CD using a ß-cyclodextrin sulfate (ß-CDS) as a possible therapeutic for fibrotic diseases caused by excess deposition of collagen fibrils. We have strategically chosen ß-CDS, which mimics the natural existence of dermatan sulfate in the extracellular matrix, for limiting collagen fibrillation. The hydrophobic nature of the inner core ß-CDS is expected to form an inclusion complex with hydrophobic side chain amino acids with the simultaneous action of forming an ionic bond through a negative charge on sulfate group with positively charged amino acids side chain in collagen. Various results suggested that such dual action not only limited the collagen fibrillation but also reduced the fibril size formed in the presence of ß-CDS. The contemporary results thus indicate that ß-CDS can be explored as a therapeutic molecule in fibrotic diseases.

Effective utilization of tannery hair waste to develop a high-performing re-tanning agent for cleaner leather manufacturing.

Accumulation of hair waste is a major burden to the leather industry, causing a negative impact on the industry's sustainable development. The industry is already bogged down by the usage of synthetic re-tanning agents that are not only extremely challenging for biodegradation but also release free-form of formaldehyde in the final leather stage. This research work focuses on developing a formaldehyde-free bio-based re-tanning agent from hair waste. In order to do so, hair waste is subjected to alkali hydrolysis and subsequently graft-copolymerized with methacrylic acid (MAA). These treatments were optimal using 20 % (w/w) sodium hydroxide and thermal activity at 90 °C. This resulted in effective hydrolysis of red sheep hair, which was the ideal candidate in this study. The hydrolysate was subjected to monomer in situ polymerization (using MAA) with potassium per sulfate/sodium meta-bisulphite redox system, leading to the development of keratin hydrolysate-g-methacrylic acid (KH-g-MA) copolymer (this was noted both at a laboratory level and pilot scale). The obtained KH-g-MA copolymer exhibited ideal characteristics such as increased protein content (78.3 ± 1.2), appropriate particle size (1516 nm), suitable pH (5) and required viscosity of 512 cP. The developed KH-g-MA copolymer was then applied as a re-tanning agent in the leather manufacturing process. Significant improvement in leather's mechanical strength characteristics was observed. In addition, the organoleptic properties of leather such as fullness, softness and grain tightness showed much improvement. Scanning electron microscopy (SEM) showed an enhanced surface smoothness and filling of the voids in experimental leather in comparison to the control leather. This recycle and reuse strategy of hair waste not only helps resolve issues with handling of hair solid waste but also results in producing an eco-friendly re-tanning agent in leather manufacturing, thereby paving the way for cyclic economic utilization and cleaner environment.

Ferulic acid loaded microspheres reinforced in 3D hybrid scaffold for antimicrobial wound dressing.

Here we report the preparation of biomimetic fibrin/chitosan/keratin hybrid scaffolds with a synergistic combination of ferulic acid loaded silica microspheres for antimicrobial wound dressing applications. The infrared and X-ray powder diffraction studies confirm the homogenous nature of the prepared hybrid scaffolds without any major interactions between the constituents. The developed hybrid scaffolds show good thermal, porosity, compression and water uptake properties. Scanning electron microscopic analysis shows that the as-synthesized ferulic acid loaded silica microspheres exhibit an average size of 35 ± 10 µm and also exposes the smooth surface with interconnected porosity in the prepared hybrid scaffolds. The incorporated ferulic acid loaded silica microspheres hybrid scaffolds show effective antimicrobial activity against the common wound pathogens. In vitro NIH3T3 fibroblast cell culture and drug release studies reveal that the prepared hybrid scaffolds have enhanced cell proliferation and adhesion with a prolonged drug release for about 72 h. In vitro wound healing and actin cytoskeleton analysis reveal that the incorporated ferulic acid loaded silica microspheres in fibrin/chitosan/keratin hybrid scaffolds facilitates cell growth and migration to damaged area through cell-cell interactions. These results suggest that the prepared hybrid scaffolds with ferulic acid loaded silica microspheres have great potential for soft tissue engineering applications particularly for the treatment of chronic and infected wounds.

In Vitro and In Vivo Evaluation of Carboxymethyl Cellulose Scaffolds for Bone Tissue Engineering Applications.

The present study involves the development of citric acid-cross-linked carboxymethyl cellulose (C3CA) scaffolds by a freeze-drying process. Scaffolds were fabricated at different freezing temperatures of -20, -40, or -80 °C to investigate the influence of scaffold pore size on bone regeneration. All three scaffolds were porous in structure, and the pore size was measured to be 74 ± 4, 55 ± 6, and 46 ± 5 µm for -20, -40, and -80 °C scaffolds. The pores were larger in scaffolds processed at -20 °C compared to -40 and -80 °C, indicating the reduction in pore size of the scaffolds with a decrease in freezing temperature. The cytocompatibility, cell proliferation, and differentiation in C3CA scaffolds were assessed with the Saos-2 osteoblast cell line. These scaffolds supported the proliferation and differentiation of Saos-2 cells with significant matrix mineralization in scaffolds processed at -40 °C. Subcutaneous implantation of C3CA scaffolds in the rat model was investigated for its ability of vascularization and new matrix tissue formation. The matrix formation was observed at the earliest of 14 days in the scaffolds when processed at -40 °C while it was observed only after 28 days of implantation with the scaffolds processed at -20 and -80 °C. These results suggest that the citric acid-cross-linked CMC scaffolds processed at -40 °C can be promising for bone tissue engineering application.

Ferulic acid-loaded collagen hydrolysate and polycaprolactone nanofibres for tissue engineering applications.

There is a great need for the progress of composite biomaterials, which are effective for tissue engineering applications. In this work, the development of composite electrospun nanofibres based on polycaprolactone (PCL) and collagen hydrolysate (CH) loaded with ferulic acid (FA) for the treatment of chronic wounds. Response Surface Methodology (RSM) has been applied to nanofibres factor manufacturing assisted by electrospinning. For wound healing applications, the authors have created the efficacy of CH, and PCL membranes can act as a stable, protective cover for wound, enabling continuous FA release. The findings of the RSM showed a reasonably good fit with a polynomial equation of the second order which was statistically acceptable at P < 0.05. The optimised parameters include the quantity of hydrolysate collagen, the voltage applied and the distance from tip-to-collector. Based on the Box-Behnken design, the RSM was used to create a mathematical model and optimise nanofibres with minimum diameter production conditions. Using FTIR, TGA and SEM, optimised nanofibres were defined. In vitro, cytocompatibility trials showed that there was an important cytocompatibility of the optimised nanofibres, which was proved by cell proliferation and cell morphology. In this research, the mixed nanofibres of PCL and CH with ferulic could be a potential biomaterial for wound healing.

Targeted delivery and apoptosis induction of trans-resveratrol-ferulic acid loaded chitosan coated folic acid conjugate solid lipid nanoparticles in colon cancer cells.

The present study is aimed to study and to evaluate the colon cancer targeting efficacy of chitosan-coated-trans-resveratrol (RSV) and ferulic acid (FER) loaded SLNs (solid lipid nanoparticles) that conjugated with folic acid (FA) (C-RSV-FER-FA-SLNs) in suitable models (in vitro). The FA conjugation is performed using co-encapsulation method of stearic acid. Similarly, the prepared SLNs are exhibited better stability even under acidic conditions to exhibit their potentials to use as drug delivery system. Further, the optimized formulations (SLNs) are tested for physiochemical characterizations, which include FTIR, XRD, 1HNMR, particle size, zeta potential, and drug release. In vitro anti-cancer studies using HT-29 cells including, fluorescence staining, flow cytometry, and western blot analysis revealed that the C-RSV-FER-FA-SLNs effectively involved and increased cytotoxicity in cancer cells that leads to induction of apoptosis as compared to free RSV-FER. Thus, it is reported that, the good stability under acidic conditions of this C-RSV-FER-FA-SLNs may serve as a promising candidate for novel nanodrug formulations in cancer therapy.

N-Vanillylnonanamide, a natural product from capsicum oleoresin, as potential inhibitor of collagen fibrillation.

Inhibition of collagen fibrillation by small molecules is of growing interest to develop therapeutics for the illnesses related to excess deposition of collagen. In this context, we have studied the inhibitory effect of N-Vanillylnonanamide (NVA), a natural product from capsicum oleoresin and an analog of capsaicin (a known inhibitor of collagen fibrillation), on collagen self-assembly that leads to fibrillation in vitro. Commercially, capsaicin was found to be expensive than NVA. Therefore, it would be an advantage economically if NVA could display a similar/better inhibitory activity compared to capsaicin. The conventional turbidity measurements indicate that NVA completely inhibits collagen fibrillation at body temperature (37 °C) and its inhibition were concentration-dependent. The inhibition efficiency was observed to reduce at room temperature (25 °C). NVA protects the triple helical structure of collagen while it increases the thermal stability of collagen compared to collagen alone. Fluorescence results suggest that NVA binds in both telopeptide and triple helical regions of collagen and thereby prevents collagen self-assembly. The present results thus indicate that NVA is a potential inhibitor and, economically, it could be a better choice as a therapeutic agent compared to capsaicin in evolving treatment for disorders associated with excessive collagen deposition.

Leather solid waste: An eco-benign raw material for leather chemical preparation - A circular economy example.

One of the long lasting problems associated with leather industry is to meet environmental standards for both liquid and solid wastes. Statistics show that one tonne of wet-salted hides/skins yields around 650 kg of solid waste. Among various wastes generated, trimmings for the most part have been underutilized. Collagen presents in trimmings waste are effectively used but hair goes unutilized or at the most as feed for boilers during gelatin manufacturing. Hence, newer technology is needed for complete and effective utilization of raw trimmings. In leather manufacture, formaldehyde condensates polymers are used as re-tanning agent to enhance the compaction of leather. However, these products are hard for biodegradation and also cause the release of free formaldehyde in leather, which is a known carcinogen. Here, there is a need for development of formaldehyde free re-tanning agent for eco-benign leather processing. In this work an attempt had been made to develop formaldehyde free biodegradable eco-benign re-tanning agent from raw trimming of tannery solid waste as a circular economy model. Alkaline (7.5%w/w NaOH) - hydrogen peroxide (10%w/w) pre-treatment followed by thermal hydrolysis at 100 °C for 5 h was an optimized method for effective hydrolysis of trimmings and the process of preparation of product results in the holistic utilization of raw trimmings. The developed product was characterized using Dynamic light scattering and FTIR techniques. The product prepared was further used in leather manufacture as a re-tanning agent and was found to impart multifunctional properties to leathers such as fullness, grain tightness and shade of dye brilliance. Product improves the mechanical strength characteristics of leather and also the exhaustion of post-tanning chemicals. SEM analysis shows that the experimental leather is more compact and flat than control. This novel strategy had not only solved the issue of solid waste but also resulted in a greener leather auxiliary leading to greener environment.

Counterion coupled (COCO) gemini surfactant capped Ag/Au alloy and Ag@Au core-shell nanoparticles for cancer therapy.

Hybrid silver (Ag)-gold (Au) nanoparticles (NPs) with different sizes and compositions were synthesized. Ag/Au alloy and Ag@Au core-shell type NPs were prepared from Ag and Au with various ratios using the COCO gemini surfactant, 1,6-bis (N,N-hexadecyldimethylammonium) adipate (COCOGS), 16-6-16 as a stabilizer. The formation of the Ag/Au alloy and Ag@Au core-shell was confirmed by UV-visible absorption spectroscopy, high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX) and selected area electron diffraction (SAED) patterns. Depending on the composition of the Ag/Au alloy NPs, the λ max values varied from 408 nm to 525 nm. FTIR measurements were used to evaluate the adsorption of the COCO gemini surfactant (16-6-16) on the Ag/Au alloy and Ag@Au core-shell surface. In this present work, we study how to achieve the stability and activity of the COCO gemini surfactant (16-6-16) capped Ag/Au alloy and Ag@Au core-shell NPs for developing novel anti-cancer agents by evaluating their potentials in the Hep-2 cell line model. Thus the developed core-shell NPs were possibly involved in inducing cytotoxicity followed by inhibition of cell proliferation to the cancer cells with apoptosis induction. The developed core-shell NPs might serve as highly applicable agents in the development of next-generation cancer chemotherapeutic agents.

Type I collagen peptides and nitric oxide releasing electrospun silk fibroin scaffold: A multifunctional approach for the treatment of ischemic chronic wounds.

Biomimetic nanofibrous scaffolds targeting multiple dysfunctional processes provide a multi-pronged strategy to restore functions and regenerate the damaged tissue. This study investigates a strategy of combining a regenerative component, Type I collagen Peptide (CP), along with a nitric oxide donor, S-Nitrosoglutathione (GSNO), in the form of nanofibrous scaffold to address the non-healing diabetic ulcer. Silk Fibroin-Polyvinyl alcohol (SF-PVA) nanofibrous scaffold is used as a carrier for delivering functional moieties. The developed nanofibrous electrospun mats (SF-PVA, CP-SF-PVA, and CP-GSNO-SF-PVA) showed continuous, bead-less and randomly oriented fibers with highly porous morphology. The in vitro biocompatibility was assessed by MTT assay, DAPI-Rhodamine 123 and FITC-Phalloidin imaging studies. CP-GSNO-SF-PVA nanofibrous scaffold showed a high degree of cell attachment, spreading of F-actin with viable cell morphology and appreciable inter-cellular connection. Thus the study showed that the proliferation of fibroblast cells are mainly facilitated by the presence of collagen peptide in the nanofibrous matrix. Griess assay demonstrated immediate release of NO for a day from the developed multifunctional scaffold. These results demonstrate the in vitro efficacy of CP-GSNO and indicate the opportunity of CP-GSNO-SF-PVA nanofibrous scaffold for the treatment of ischemic non-healing ulcers.

Collagen-silica bio-composite enriched with Cynodon dactylon extract for tissue repair and regeneration.

Development of biomaterials for tissue engineering applications is of great interest to meet the demand of different clinical requirements. The wound heal dressing biomaterials should necessarily contain well-defined therapeutic components and desirable physical, chemical and biological properties to support optimal delivery of therapeutics at the site of the wound. In this study, we developed collagen-silica wound heal scaffold incorporated with the extract of Cynodon dactylon, characterized and evaluated for its wound heal potential in vitro and in vivo against collagen (Col) and Collagen-silica (CS) scaffolds that served as controls. The prepared Collagen-Silica-Cynodon extract (CSCE) scaffold exhibits porous morphology with preferable biophysical, chemical, mechanical and mass transfer properties besides its controlled biodegradation at the wound site. Stability of CSCE was found to be better than that of native collagen due to intermolecular interactions between collagen and constituents of C. dactylon as confirmed by FTIR analysis. Notably, in vitro biocompatibility assay using DAPI and Rhodamine 123 staining demonstrated that the proliferation of NIH3T3 fibroblast cells was better for CSCE when compared to the Col and CS scaffolds. In vivo wound healing experiments with full-thickness excision wounds in wistar rat model demonstrated that the wounds treated with CSCE showed accelerated healing with enhanced collagen deposition when compared to wounds treated with Col and CS scaffolds, and these studies substantiated the efficacy of CSCE scaffold for treating wounds.

Leprosy-associated Chronic Wound Management Using Biomaterials.

BACKGROUND: Deformities and neuropathic chronic ulcers are the common features associated with leprosy-cured individuals that impact their quality of life and impair rehabilitation efforts. The challenging aspects for treatment of chronic wounds are the factors that inhibit healing. We reasoned that limited success of various therapeutic interventions could be due to the fact that leprosy-cured individual's physiology gets acclimatized to having a chronic wound that any therapeutic intervention is counterbalanced to maintain status quo at the wound site. Therefore, an alternative strategy would be to use biomaterials that gradually alter the wound site allowing the individual's physiology to participate in the healing process. AIMS: Developing the human amnion (Amn)-derived biomaterial scaffolds and evaluating its use to heal chronic wounds in leprosy-cured but deformed persons (LCDPs). MATERIALS AND METHODS: Using an enzymatic protocol, we have developed a rapid method to generate biomaterial scaffolds from discarded human Amn. A clinical trial on 26 LCDPs was performed with the biomaterial, and its wound-healing potential was then compared with LCDPs undergoing standard treatment procedure. RESULTS: Biomaterial-based treatment of chronic wounds on LCDP displayed a higher efficiency in healing when compared to standard treatment. CONCLUSIONS: This study exemplifies that biomaterial-based treatment of leprosy-wounds offers an excellent affordable alternative for wound management. This study underlines the importance of involving both local wound environment and systemic effects for healing. In addition, we highlight wound healing as a necessity for successful rehabilitation and reintegration of leprosy-cured person into the society.

Selective binding and dynamics of imidazole alkyl sulfate ionic liquids with human serum albumin and collagen - a detailed NMR investigation.

The interaction of ionic liquid (IL) with protein is now becoming important as it stabilizes the protein due to the selective cation-anion combination of the IL. The binding and dynamics of the green solvents such as imidazole alkyl sulfate based ILs, viz., 1-butyl-3-methylimidazolium alkyl [where alkyl = hydrogen, methyl, octyl and dodecyl] sulfate, with two distinct model proteins, namely human serum albumin (HSA) and collagen in aqueous solution, have been investigated with the aid of solution nuclear magnetic resonance (NMR). Interactions of ILs with HSA and collagen have been probed at the atomistic level through NMR determined parameters, such as 1H line-shapes, selective and non-selective spin-lattice relaxation times (T1SEL & T1NS) and spin-spin relaxation times (T2). Furthermore, saturation transfer difference (STD) NMR has been used to monitor the spatial proximities of ILs with HSA and collagen. The results indicate that despite the type of protein (HSA or collagen), STD NMR of protein-IL mixtures exhibits responses only from the anionic part of the selected ILs. Also, a combination of T1SEL and T1NS measurements indicates the genuine protein-IL interaction. Furthermore, it was observed that the global binding affinity between IL and proteins is enhanced with an increase in alkyl chain length of the anionic portion of the IL. The present study thus highlights the role of the anionic part of ILs in the interaction with the selected proteins. The outcome of the present study provides an opportunity to design new ILs with a judicious choice of anionic and cationic parts for targeted functionalities.