Showing papers on "Gelatin published in 2003"
TL;DR: In this article, the reaction mechanism of chitosan, bovine serum albumin (BSA), and gelatin with genipin (a natural crosslinking reagent) was examined with infrared, ultraviolet-visible, and 13C NMR spectroscopies; protein-transfer reaction mass spectrometry; photon correlation spectroscopy; and dynamic oscillatory rheometry.
Abstract: The reaction mechanism of chitosan, bovine serum albumin (BSA), and gelatin with genipin (a natural crosslinking reagent) was examined with infrared, ultraviolet–visible, and 13C NMR spectroscopies; protein-transfer reaction mass spectrometry; photon correlation spectroscopy; and dynamic oscillatory rheometry. Two reactions that proceeded at different rates led to the formation of crosslinks between primary amine groups. The fastest reaction to occur was a nucleophilic attack on genipin by a primary amine group that led to the formation of a heterocyclic compound of genipin linked to the glucosamine residue in chitosan and the basic residues in BSA and gelatin. The second, slower, reaction was the nucleophilic substitution of the ester group possessed by genipin to form a secondary amide link with chitosan, BSA, or gelatin. A decreased crosslinking rate in the presence of deuterium oxide rather than water suggested that acid catalysis was necessary for one or both of the reactions to proceed. The behavior of the gel time with polymer concentration was consistent with second-order gelation kinetics resulting from an irreversible crosslinking process, but was complicated by the oxygen radical-induced polymerization of genipin that caused the gels to assume a blue color in the presence of air. The lower elastic modulus attained after a given time during crosslinking of the globular protein BSA as compared to the coiled protein gelatin, despite possessing more crosslinkable basic residues, demonstrated the importance of protein secondary and tertiary structures in determining the availability of sites for crosslinking with genipin in protein systems. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3941–3953, 2003
541 citations
TL;DR: Genetic engineering has made great progress in the areas of recombinant collagen and gelatin expression, and there are now several alternatives to bovine material that offer an enhanced safety profile, greater reproducibility and quality, and the ability of these materials to be tailored to enhance product performance.
479 citations
TL;DR: The development of HAp nanocrystals in an aqueous GEL solution was highly influenced by the concentration ratio of GEL to HAp, and the formation of a primary chemical bond between HAp and GEL showed a strong preferred orientation of the (002) plane in HAp Nanocrystals.
408 citations
TL;DR: The results suggest that the soft and elastic complex of chitosan and gelatin, which has better nerve cell affinity compared to chito-gelatin, is a promising candidate biomaterial for nerve regeneration.
392 citations
TL;DR: Results demonstrate that disulfide-crosslinked HA-gelatin hydrogels, a new type of covalent synthetic ECM, constitute biocompatible and biodegradable substrata for cell culture in vitro.
374 citations
TL;DR: It was observed that the transglutaminase-catalyzed gelatin-chitosan gels lost the ability to undergo thermally reversible transitions characteristic of gelatin, which suggests that gelatin's ability to undergoing a collagen-like coil-to-helix transition is unaffected by tyrosinase- catalyzed reactions.
349 citations
TL;DR: The results suggested that the porosity and pore size of the scaffolds could be modulated with thermodynamic and kinetic parameters of ice formation and can be utilized as a promising matrix for tissue engineering.
344 citations
TL;DR: The controlled release technology of BMP-2 for a certain time period was essential to induce the potential activity for bone formation as well as to develop a carrier for the controlled release of bone morphogenetic protein-2 suitable for enhancement of the bone regeneration activity.
339 citations
TL;DR: Combination of gelatin microspheres containing bFGF and preadipocytes with the collagen sponge is essential to achieve tissue engineering of fat tissue.
277 citations
TL;DR: The data from this study suggest that chitosan-gelatin scaffolds are suitable for skin tissue engineering goals.
Abstract: A novel absorbable scaffold composed of chitosan and gelatin was fabricated by freezing and lyophilizing methods, resulting in an asymmetric structure. This bilaminar texture is suitable for preparing a bilayer skin substitute. The methods employed to confirm the applicability of this chitosan-gelatin scaffold as an ideal skin substitute were a water uptake ability test, in vitro fibroblast proliferation, and scaffold tests in which fibroblasts were co-cultured with keratinocytes. The chitosan-gelatin scaffolds were more wettable and adsorbed more water than did chitosan alone. In static cell culture the thinner scaffold is better than the thicker one, and because of diffusion limitations in the scaffold, culture time must be within 3 weeks before transplantation to living tissues. Keratinocytes were co-cultured with fibroblasts in chitosan-gelatin scaffolds to construct an artificial bilayer skin in vitro. The artificial skin obtained was flexible and had good mechanical properties. Moreover, there was no contraction observed in the in vitro cell culture tests. The data from this study suggest that chitosan-gelatin scaffolds are suitable for skin tissue engineering goals.
248 citations
TL;DR: The results provide a method of achieving prolonged drug release through self-assembly of polymeric shells on drug microcrystals through layer-by-layer (LbL) assembly.
TL;DR: Results show that gelatin/chondroitin sulfate/hyaluronan tri-copolymer has potential for use as a cartilage tissue engineering scaffold.
TL;DR: The combined results indicate that the kinetics of TGF-beta1 release can be controlled by adjusting OPF formulation and microparticle loading, factors affecting the swelling behavior these composites.
TL;DR: The results suggest that the scaffolds can be utilized in nonloading bone regeneration and improved compressive properties were improved, especially compressive modulus from 3.9-10.9 MPa.
Abstract: A biodegradable composite scaffold was developed using beta-tricalcium phosphate (beta-TCP) with chitosan (CS) and gelatin (Gel) in the form of a hybrid polymer network (HPN) via co-crosslinking with glutaraldehyde. Various types of scaffolds were prepared by freezing and lyophilizing. These scaffolds were characterized by Fourier transform infrared, X-ray diffractometer, and scanning electron microscopy. The macroporous composite scaffolds exhibited different pore structures. Compressive properties were improved, especially compressive modulus from 3.9-10.9 MPa. Biocompatibility was evaluated subcutaneously on rabbits. A mild inflammatory response was observed over 12 weeks. The results suggest that the scaffolds can be utilized in nonloading bone regeneration.
TL;DR: A naturally occurring crosslinking agent (genipin) was used to crosslink gelatin microspheres as a biodegradable drug-delivery system for intramuscular administration and indicated that the genipin-crosslinked gelatinmicrospheres may be used as a long-acting drug carrier for intramscular administration.
Abstract: Gelatin microspheres have been widely evaluated as a drug carrier. Nevertheless, gelatin dissolves rather rapidly in aqueous environments, making the use of the polymer difficult for the production of long-term delivery systems. This adverse aspect requires the use of a crosslinking agent in forming nonsoluble networks in microspheres. However, the use of crosslinking agents such as formaldehyde and glutaraldehyde can lead to toxic side effects owing to residual crosslinkers. In an attempt to overcome this problem, a naturally occurring crosslinking agent (genipin) was used to crosslink gelatin microspheres as a biodegradable drug-delivery system for intramuscular administration. Glutaraldehyde was used as a control. In the in vitro study, the morphology, dynamic swelling, and antienzymatic degradation of test microspheres were evaluated. In the in vivo study, the biocompatibility and degradability of test microspheres were implanted in the skeletal muscle of a rat model via intramuscular injection. The results obtained in the study suggested that crosslinking of gelatin microspheres with glutaraldehyde or genipin may produce distinct crosslinking structures. The water transport mechanism in both the glutaraldehyde- and genipin-crosslinked gelatin microspheres exhibit anomalous behavior ranging from Fickian to Case-II extremes. The increase of the swelling diameter for the genipin-crosslinked microspheres was significantly less than that observed for the glutaraldehyde-crosslinked microspheres. In the animal study, it was found that the degree in inflammatory reaction for tissues implanted with the genipin-crosslinked microspheres was significantly less than that implanted with the glutaraldehyde-crosslinked microspheres. Additionally, the degradation rate of the genipin-crosslinked microspheres was significantly slower than their glutaraldehyde-crosslinked counterparts. These results indicated that the genipin-crosslinked gelatin microspheres may be used as a long-acting drug carrier for intramuscular administration.
TL;DR: G gelatin coated mica surfaces are shown to be suitable for immobilizing and imaging both gram positive, Staphylococcus aureus, and gram negative, Escherichia coli, bacteria in both air and liquid environments.
TL;DR: The results indicated that genipin is a good cross-linker for the gelatin and should not exceed 0.5% of the overall weight of the gelatin-based material if a complete cross-linking reaction between gelatin and Genipin molecules is required.
TL;DR: In this paper, the location of the stabilizer using fluorescence microscopy was observed using rhodamine isothiocyanate and incorporated into solutions of sucrose with or without milk solids-not-fat (MSNF).
TL;DR: The incorporation of hyaluronic acid improved flexibility and fibroblasts adhesion, while slowing down the rate of biodegradation of chitosan-gelatin scaffold.
TL;DR: These gelatin microparticles containing propolis would be useful for developing intermediary or eventual propolis dosage form without the PES' strong and unpleasant taste, aromatic odour, and presence of ethanol.
TL;DR: The influence of temperature and pH on the acidification of a synthetic gelatin based wastewater was investigated using an upflow anaerobic reactor and the optimum pH for the overall acidogenic activity was found to be 6.0-7.0, close to 5.9, the optimum GPA calculated using a semi-empirical model.
TL;DR: Hydrogels based on poly(acrylic acid) and gelatin crosslinked with N,N'-methylene bisacrylamide and glutaraldehyde, forming an interpenetrating network were employed as matrices, for studying the loading and release of gentamicin sulphate, and rate of drug release was faster as compared to water or citrate buffer.
TL;DR: In the in vivo study, it was found that the degree of inflammatory reaction for the wound treated with the genipin-crosslinked dressing was significantly less severe than that covered with the glutaraldehyde-cross linked dressing throughout the entire course of the study.
Abstract: A naturally occurring crosslinking agent (genipin) was used in this study to crosslink gelatin hydrogel to develop a wound-dressing membrane. The study was to investigate the in vitro characteristics of the genipin-crosslinked gelatin membrane. The glutaraldehyde-crosslinked counterpart, at a similar crosslinking degree, was used as control. Additionally, an in vivo experiment was undertaken to study the wound healings covered with the glutaraldehyde- and genipin-crosslinked dressings in a rat model. The in vitro results obtained suggested that crosslinking of gelatin membranes with glutaraldehyde or genipin may produce distinct crosslinking structures. The differences in crosslinking structure can significantly affect the mechanical property, water-vapor-transmission rate, swelling ratio, degradation against enzyme and cellular compatibility of the crosslinked membranes. In the in vivo study, it was found that the degree of inflammatory reaction for the wound treated with the genipin-crosslinked dressing was significantly less severe than that covered with the glutaraldehyde-crosslinked dressing throughout the entire course of the study. Additionally, the healing rate for the wound treated with the genipin-crosslinked dressing was notably faster than its glutaraldehyde-crosslinked counterpart.
TL;DR: An in vivo study showed that after 1 week, the artificial dermis containing the fibroblasts enhanced the re-epithelialization of a full-thickness skin defect rather than the acellular scaffold.
TL;DR: The traditional sources of gelatin include bovine and pig skins and demineralized bones and hooves as mentioned in this paper, however, recent studies have shown that marine fish skins and bones can also be used as new sources.
Abstract: Of all the hydrocolloids in use today, surely none has proven as popular with the general public and found favor in as wide a range of food products as gelatin. A sparkling, clear dessert jelly has become the archetypal gel and the clean melt‐in‐the‐mouth texture is a characteristic that has yet to be duplicated by any polysaccharide. Despite its apparently unfashionable status, more gelatin is sold to the food industry than any other gelling agent. It is relatively cheap to produce in quantity, and there is a ready supply of suitable raw material. The traditional sources of gelatin include bovine and pig skins and demineralized bones and hooves. However, recent studies have shown that there are viable new sources of gelatin such as marine fish skins and bones. Researchers have further sought to develop gelatin derivatives or modified gelatins like coldwater soluble gelatin, hydrolyzed gelatin and esterified gelatin.
TL;DR: It is suggested that T-Gase-mediated incorporation of cell adhesion factors into gelatin matrices enhanced cell proliferation and this novel biomaterial is a potent tool for wound dressing or tissue engineering.
TL;DR: In this article, an injectable and in situ gelable scaffold can fully fill the space of cartilaginous defects of complex shapes, and the authors attempted to develop a novel injection-driven technique for cartilage rep...
Abstract: An injectable and in situ gelable scaffold can fully fill the space of cartilaginous defects of complex shapes. The authors attempted to develop a novel injection-driven technique for cartilage rep...
TL;DR: In vivo studies showed that gelatin-based hydrogels elicited comparable levels of acute and chronic inflammatory response as that of the empty cage control by 21 d, and modification of gelatin with PEG-dial and EDTAD had no effect on T(max), R(fail), or T(fail).
TL;DR: Findings demonstrate that the controlled release of CDDP was based on biodegradation of the hydrogel carrier, but not simple diffusion of CDSP, which suppressed in vivo tumor growth and retention.
TL;DR: The role played by solution entropy in addition to that of electrostatic and solute-solvent interactions, which had been overlooked hitherto, is revealed.