Dual crosslinked collagen/chitosan film for potential biomedical applications

The application of polymeric biomaterial scaffolds utilizing crosslinking strategy has become an effective approach in these days. In the present study, the development and characterization of collagen-chitosan hydrogel film has been reported on using dual crosslinking agent's, i.e., tannic acid and genipin simultaneously. Incorporation of genipin imparts a greenish-blue color to the polymeric film. The effect of dual crosslinking and their successful interaction within the matrix was evaluated by infrared analysis spectroscopy. The porosity of the film was examined using scanning electron microscopy (SEM). Results of TGA determine the intermediate thermal degradation. Further, the crosslinking phenomenon has found primary impact on the strength of the films. Enzymatic degradation for the films was performed with lysozyme and lipase. The cell adhesion and proliferation was also accomplished using mouse embryonic cell lines wherein the cells cultured on the dual crosslinked film. The thriving utilization of such dual crosslinked polymeric film finds their applications in ophthalmology especially as an implant for temporary injured cornea and skin tissue regeneration.Ministry of Education, Youth and Sports of the Czech Republic-Program NPUI [LO1504

Influence of temperature, pH and simulated biological solutions on swelling and structural properties of biomineralized (CaCO3) PVP-CMC hydrogel

Biomaterials having stimuli response are interesting in the biomedical field. This paper reports about swelling response and internal structural of biomineralized (CaCO3) polyvinylpyrrolidone (PVP) carboxymethylcellulose (CMC) hydrogel having various thicknesses (0.1-0.4 mm). Samples were tested in aqueous solution using temperature ranges from 10 to 40 degrees C; pH varies from 4 to 9, time 60 min. In addition, an experiment was conducted in the presence of simulated biological solutions (SBS): glucose (GS), physiological fluid (PS) and urea US) at temperature 37 degrees C and pH 7.5 for 180 min. It is noticed that the maximum swelling ratio reached in 30-40 degrees C at pH 7 in aqueous solution. Among biological fluids, the swelling ratio shows: US[PS[GS at temperature 37 degrees C, pH 7.5, time 150 min. The equilibrium swelling ratio of the test sample in SBS and their non-reformative apparent structure confirm that biomineralized (CaCO3) PVP-CMC hydrogel can be acclaimed for medical application like bone tissue engineering

Mineralized polymer composites as biogenic bone substitute material

Mineralized polymer composites (MPC) are recognized as potential fillers of bone defects. Though bioceramics exhibits quite a good bone-bonding and vascularization, it is considered to be too stiff and brittle for using alone. Thus, the use of polymer scaffold instead of bioceramics has several advantages including combining the osteoconductivity and bone-bonding potential of the inorganic phase with the porosity and interconnectivity of the three-dimensional construction. Aiming the advantages of ceramic-polymer composite scaffolds, the calcium carbonate (CaCO3) based biomineralized scaffold was prepared, where the PVP-CMC hydrogel was used as an extracellular matrix. This paper is reported about the morphology, swelling trend (in physiological solution) and viscoelastic behavior of (90 min mineralized) MPC. The dry MPC are off-white, coarse in texture, comparatively less flexible than the original PVP-CMC based hydrogel film, and the deposition of granular structures on the surface of the hydrogel film confirms about the development of biomineralized scaffold/polymer composites. Irrespective of thickness, the dry MPC shows higher values of swelling ratio within 30 min, which varies between 200-250 approximately. The dynamic viscoelastic nature of freshly prepared MPC was investigated applying 1% and 10% strain. At higher strain the viscoelastic moduli (G' and G '') show significant change, and the nature of MPC turns from elastic to viscous. Based on the observed basic properties, the MPC (calcite based polymer composites) can be recommended for the treatment of adyanamic bone disorder

Preparation of bacterial cellulose based hydrogels and their viscoelastic behavior

Bacterial cellulose (BC) based hydrogels have been prepared in blended with carboxymethylcellulose and polyvinyl pyrrolidone by using heat treatment. The properties of BC-CMC and BC-PVP hydrogels were compared with pure BC, CMC and PVP hydrogels. These hydrogels were investigated by measuring their structural, morphological and viscoelastic properties. Through the morphological images, alignment of the porous flake like structures could be seen clearly within the inter-polymeric network of the hydrogels. Also, the detail structure analysis of the polymers blended during the hydrogel formation confirms their interactions with each other were studied. Further, the viscoelastic behavior of all the hydrogels in terms of elastic and viscous property was studied. It is observed that at 1% strain, including CMC and PVP hydrogels, all the BC based hydrogels exhibited the linear trend throughout. Also the elastic nature of the material remains high compared to viscous nature. Moreover, the changes could be noticed in case of blended polymer based hydrogels. The values of complex viscosity (eta*) decreases with increase in angular frequency within the range of omega = 0.1-100 rad.s(-1)

Dual Crosslinked Collagen/Chitosan Film for Potential Biomedical Applications

The application of polymeric biomaterial scaffolds utilizing crosslinking strategy has become an effective approach in these days. In the present study, the development and characterization of collagen–chitosan hydrogel film has been reported on using dual crosslinking agent’s, i.e., tannic acid and genipin simultaneously. Incorporation of genipin imparts a greenish-blue color to the polymeric film. The effect of dual crosslinking and their successful interaction within the matrix was evaluated by infrared analysis spectroscopy. The porosity of the film was examined using scanning electron microscopy (SEM). Results of TGA determine the intermediate thermal degradation. Further, the crosslinking phenomenon has found primary impact on the strength of the films. Enzymatic degradation for the films was performed with lysozyme and lipase. The cell adhesion and proliferation was also accomplished using mouse embryonic cell lines wherein the cells cultured on the dual crosslinked film. The thriving utilization of such dual crosslinked polymeric film finds their applications in ophthalmology especially as an implant for temporary injured cornea and skin tissue regeneration

Preparation of CaCO3-based biomineralized polyvinylpyrrolidone-carboxymethylcellulose hydrogels and their viscoelastic behavior

In the blend of natural and synthetic polymer-based biomaterial of polyvinylpyrrolidone (PVP) and carboxymethylcellulose (CMC), fabrication of CaCO3 was successfully accomplished using simple liquid diffusion technique. The present study emphasizes the biomimetic mineralization in PVP-CMC hydrogel, and furthermore, several properties of this regenerated and functionalized hydrogel membranes were investigated. The physical properties were studied and confirmed the presence of CaCO3 mineral in hydrogel by Fourier transform infrared spectroscopy and Scanning electron microscopy. Moreover, the absorptivity of water and mineral by PVP-CMC hydrogel was studied to determine its absorption capacity. Further, the viscoelastic properties (storage modulus, loss modulus, and complex viscosity) of mineralized and swelled samples (time: 5-150 min) were measured against angular frequency. It is interesting to know the increase of elastic nature of mineralized hydrogel filled with CaCO3 maintaining the correlation between elastic property and viscous one of pure hydrogel. All these properties of biomineralized hydrogel suggest its application in biomedical field, like bone treatment, bone tissue regeneration, dental plaque and tissue replacement, etc. © 2013 Wiley Periodicals, Inc.Research and Development for Innovation Operational Program; European Regional Development Fund (ERDF); national budget of the Czech Republic [CZ.1.05/2.1.00/03.0111, CZ.1.07/2.3.00/20.0104]; "Education for Competitiveness" Operational Program; European Social Fund (ESF

Influence of strain on dynamic viscoelastic properties of swelled (H<inf>2</inf>O) and biomineralized (CaCO<inf>3</inf>) PVP-CMC hydrogels

This paper reports the rheological behavior of swelled and mineralized hydrogel prepared using polyvinylpyrrolidone (PVP) and carboxymethylcellulose (CMC) hydrogel as base polymer. Herein, the bio-mineral calcium carbonate (CaCO3) was incorporated into the hydrogel using simple liquid diffusion method. The morphology of the swelled and mineralized hydrogel was analyzed through scanning electron microscopy. Further, the normalized time of absorptivity was identified from the time dependent absorptivity behavior of calcite and water filled PVP-CMC hydrogel. The effect of the biomineral (CaCO3) and water on the dynamic viscoelastic properties, after penetrating inside the hydrogel matrix has been evaluated. The frequency sweep at 1 and 10 % strain and also strain sweep measurement were performed to determine the frequency and strain dependent viscoelastic moduli G' and G" of both swelled and mineralized hydrogel. At higher strain the both moduli showed significant change over wide range of angular frequency region and the nature of mineralized polymer composites (MPC) turned from elastic to viscous. Based on the observed basic properties, MPC (calcite based polymer composites) can be recommended for the treatment of adyanamic bone disorder and water swelled hydrogel can be acclaimed as a scaffold for burned wound dressing. © Applied Rheology.Operational Programme Research and Development for Innovation; European Regional Development Fund (ERDF); national budget of Czech Republic [CZ.1.05/2.1.00/03.0111]; Operational Programme "Education for Competitiveness"; European Social Fund (ESF); national budget of the Czech Republic, within the "Advanced Theoretical and Experimental Studies of Polymer Systems" project [CZ.1.07/2.3.00/20.0104

Hydrogel-based biomaterial sensitive to magnetic stimuli

Biomateriál je tvořen kompozitem hydrogelové matrice na bázi polyvinylpyrrolidon-karboxymetylcelulozy (PVP-CMC)Biomaterial is made of a composite of hydrogel matrix on the basis of polyvinylpyrrolidone carboxymethylcellulose (PVP-CMC)

Stimuli responsive and biomineralized scaffold: An implant for bone-tissue engineering

Development of bioactive and stimuli responsive materials in the form of implant/scaffold is the urgent need that mimics the natural bone structure and function. To achieve such novel smart biomaterials "PVP-CMC-CaCO3" scaffold was prepared using PVP-CMC hydrogel as a matrix, following the biomimetic mineralization process i.e. simple liquid diffusion technique. The main concern of this study is to establish its stimuli responsive nature as it is one of the important factor of biomaterials. The swelling-deswelling capacity of "PVP-CMC-CaCO3" scaffold was carried out at 37°C using physiological solution. The morphological changes which occurred in the biomineralized scaffold during swellingdeswelling-reswelling and deswelling steps were confirmed using scanning electron microscopy. The obtained results concerning shape-size and thickness indicated that PVP-CMC-CaCO3, a hydrogel based scaffold is a true stimuli responsive biomaterial

Effect of strain on viscoelastic behavior of fresh, swelled and mineralized PVP-CMC hydrogel

Mineralization of calcium carbonate (CaCO3) in hydrogel matrix is one of the most interesting topics of research by material scientists for the development of bio-inspired polymeric biomaterial for biomedical applications especially for bone tissue regeneration. As per our knowledge there was no work reported about rheological properties of CaCO3 mineralized hydrogel though some works have done on mineralization of CaCO3 in various gel membranes, and also it was reported about the viscoelastic properties of Agarose, Cellulose, PVA and PVP-CMC hydrogels. This paper mainly focuses about the effect of strain on viscoelastic properties of fresh, swelled and mineralized (CaCO3) PVP-CMC hydrogel. All these three types of hydrogel sustain (or keep) strictly the elastic properties when low strain (1%) is applied, but at higher strain (10%) the viscoelastic moduli (G' and G '') show significant change, and the nature of these materials turned from elastic to viscous