The aim of this study was to fabricate composite gel beads based on natural polysaccharides. Hyaluronic acid（HA） and Chitosan（CS） were successfully admixed with Ca^2＋/alginate（SA） gel system to produce SA/HA/CS...The aim of this study was to fabricate composite gel beads based on natural polysaccharides. Hyaluronic acid（HA） and Chitosan（CS） were successfully admixed with Ca^2＋/alginate（SA） gel system to produce SA/HA/CS gel beads by dual crosslinking： the ionic gelation and the polyelectrolyte complexation. The preparation procedure was that the weight ratio of SA（2%, m/v） to HA（2%, m/v） was kept at 2：1, then the mixture was dripped into the Ca^2＋ solution for ion-crosslinking, and finally polyelectrolyte crosslinked with 2% low molecular weight CS（LMW-CS） for 1.5 hours. The optimal formulation was achieved by adjusting the concentration and the weight ratio of SA, HA and LMW-CS. Due to the incorporation of HA and LMWCS, the swelling ratio of the beads at pH 7.4 was increased up to 120, and the time for the maximum swelling degree was prolonged to 7.5 h. The swelling behavior was obviously improved compared to the pure SA/Ca^2＋ system. The preliminary results clearly suggest that the SA/HA/CS gel beads may be a potential candidate for biomedical delivery vehicles.展开更多
Low molecular weight N-succinyl-chitosans with different degrees of substitution were synthesized by controlling reaction temperature, reaction time, and the molar ratio of the low molecular weight chitosan to succini...Low molecular weight N-succinyl-chitosans with different degrees of substitution were synthesized by controlling reaction temperature, reaction time, and the molar ratio of the low molecular weight chitosan to succinic anhydride. The structure of the low molecular weight N-succinyl-chitosan was characterized by infrared spectroscopy(IR), by which —COCH_ 2CH_ 2COOH was proved to be introduced to the —NH_ 2 of the low molecular weight chitosan. The moisture adsorption and moisture retention capacities of the low molecular weight chitosan derivatives with different degrees of substitution were investigated. The results indicate that the moisture adsorption and moisture retention capacities of the low molecular weight N-succinyl-chitosan increase with the increase of the degree of substitution. When the degree of substitution is greater than 38%, the derivatives have better moisture adsorption and moisture retention capacities than hyaluronic acid.展开更多
基金Funded by the National Natural Science Foundation of China(No.81401510)
文摘The aim of this study was to fabricate composite gel beads based on natural polysaccharides. Hyaluronic acid（HA） and Chitosan（CS） were successfully admixed with Ca^2＋/alginate（SA） gel system to produce SA/HA/CS gel beads by dual crosslinking： the ionic gelation and the polyelectrolyte complexation. The preparation procedure was that the weight ratio of SA（2%, m/v） to HA（2%, m/v） was kept at 2：1, then the mixture was dripped into the Ca^2＋ solution for ion-crosslinking, and finally polyelectrolyte crosslinked with 2% low molecular weight CS（LMW-CS） for 1.5 hours. The optimal formulation was achieved by adjusting the concentration and the weight ratio of SA, HA and LMW-CS. Due to the incorporation of HA and LMWCS, the swelling ratio of the beads at pH 7.4 was increased up to 120, and the time for the maximum swelling degree was prolonged to 7.5 h. The swelling behavior was obviously improved compared to the pure SA/Ca^2＋ system. The preliminary results clearly suggest that the SA/HA/CS gel beads may be a potential candidate for biomedical delivery vehicles.
文摘Low molecular weight N-succinyl-chitosans with different degrees of substitution were synthesized by controlling reaction temperature, reaction time, and the molar ratio of the low molecular weight chitosan to succinic anhydride. The structure of the low molecular weight N-succinyl-chitosan was characterized by infrared spectroscopy(IR), by which —COCH_ 2CH_ 2COOH was proved to be introduced to the —NH_ 2 of the low molecular weight chitosan. The moisture adsorption and moisture retention capacities of the low molecular weight chitosan derivatives with different degrees of substitution were investigated. The results indicate that the moisture adsorption and moisture retention capacities of the low molecular weight N-succinyl-chitosan increase with the increase of the degree of substitution. When the degree of substitution is greater than 38%, the derivatives have better moisture adsorption and moisture retention capacities than hyaluronic acid.
