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In the current study, kappa carrageenan (κ-carr) and gelatin (gel) based hemostatic sponges were fabricated for dental applications. The K-carr and gel based dental sponges were characterized by attenuated total reflection-Fourier transform infrared spectroscopy. The morphological properties of the dental sponges were observed by Scanning Electron Microscope analysis. Thermal properties of sponges were evaluated by Thermogravimetric Analysis. The swelling and hydrolytic degradation percentages of the dental sponges were investigated in pH 6.8 to mimic oral saliva. The mechanical properties of the dental sponges were determined and were found to be higher in comparison with the commercial sponge. The sponges reached approximately 95% blood absorption at the end of 45 min. κ-carr and gel based dental sponges did not show cytotoxic effects on the L929 fibroblast cell line in thiazolyl blue tetrazolium bromide cell viability assay. All results suggested that the developed κ-carr and gel based dental sponges demonstrate great potential for dental applications for the future health care materials.

The aim of this research was to investigate the potential of ampicillin-loaded hydrogels based on polyvinyl alcohol (PVA), hyaluronic acid (HA) and kappa-carrageenan (K-Carr) as an antibiotic-releasing wound dressing. Firstly, the novel polymers (HA-g-K-Carr) were synthesized by grafting of HA onto K-Carr using 4-dimethylaminopyridine/1-(3-dimethylaminopyl)-3-ethyl-carbodiimide hydrochloride as catalyst system via esterification reaction. The characterization of the polymer structure was performed by Fourier transform infrared spectrum (FTIR), proton nuclear magnetic resonance and thermogravimetric analysis. Secondly, PVA/(HA-g-K-Carr) hydrogel with/without loading of ampicillin molecules was formed via freeze–thawing method since PVA/K-Carr and PVA/HA hydrogels were also fabricated as control groups. The hydrogels were subjected to characterizations with FTIR and X-ray diffractometer. PVA/(HA-g-K-Carr) hydrogel demonstrated the highest swelling amount and highest ampicillin release amount reaching an equilibrium value after 480 min rather than the other hydrogels. Also, PVA/(HA-g-K-Carr) hydrogel exhibited inhibition zone against Escherichia coliand Staphylococcus aureusand no cytotoxic effect for L929 cells. All the results showed that PVA/(HA-g-K-Carr) hydrogels are good candidates for wound dressing applications.

The current work was aimed to prepare bacterial cellulose/poly vinyl alcohol (BC/PVA) wound dressings loaded with antibiotic which were prepared via freeze-thawing. The swelling ratio of BC/PVA hydrogels was in the range of 188–240%. The water loss percentage of BC was improved with the addition of PVA. 30% of the cumulative ampicillin delivery from BC/PVA hydrogels was achieved during 120 h suggesting significant role of PVA incorporation since 50% of ampicillin was released from BC after 24 h. BC/PVA hydrogels showed great antibacterial activity against E.coliand S. aureus. The results revealed that BC/PVA hydrogels presented great potential as wound dressings with high swelling ratio, low water loss percentage and slow antibiotic release properties.

Molecular imprinting is an attractive biomimetic approach that creates specific recognition sites for the shape and functional group arrangement to template molecules. The purpose of this study is to prepare cytochrome c‐imprinted poly(hydroxyethyl methacrylate) (PHEMA)‐based supermacroporous cryogel which can be used for the separation of cytochrome cfrom protein mixtures. N‐Methacryloyl‐(L)‐histidinemethylester (MAH) was used as the metal‐coordinating monomer. In the first step, Cu2+was complexed with MAH, and the cytochrome cimprinted PHEMA (MIP) cryogel was prepared by free radical cryopolymerization initiated by N,N,N′,N′‐tetramethylene diamine at −12°C. After polymerization is completed, the template cytochrome cmolecules were removed from the MIP cryogel using 0.5 M NaCl solution. The maximum cytochrome cbinding amount was 126 mg/g polymer. Selective binding studies were performed in the presence of lysozyme and bovine serum albumin. The relative selectivity coefficients of MIP cryogel for cytochrome c/lysozyme and cytochrome c/bovine serum albumin were 1.7 and 5.2 times greater than those of the non‐imprinted PHEMA cryogel, respectively. The selectivity of MIP cryogel for cytochrome cwas also confirmed with fast protein liquid chromatography. The MIP cryogel could be used many times with no remarkable decrease in cytochrome cbinding capacity.

In this study, the novel multilayer (ML) hydrogels were developed as antibacterial wound dressings. ML hydrogels were prepared as four layers using carboxylated polyvinyl alcohol (PVA-C), gelatin (G), hyaluronic acid (HA) and gelatin respectively. The upper layers (PVA-C and G) provide the moist control and physical barrier for microorganisms. The HA based middle layer was designed as an antibiotic-loaded layer. The lower layer serves as the controlling membrane for antibiotic release and provides the removal of excess exudate from the wound site. The ML hydrogels were characterized with FT-IR, SEM, DSC, swelling tests and hydrolytic degradation tests. Cell viability assay was also performed in L929 fibroblast cells in vitro. The in-vitro drug release profile of ML hydrogels was investigated at pH 7.4 at 37 °C and it was found that 63% of the antibiotic was released after 7 days.