• Polymer(Korea)
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• v.27 no.6
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• pp.583-588
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• 2003

Sulfated chitosan and sulfated sodium alginate were synthesized by sulfating reaction of low molecular chitosan and low molecular sodium alginate with SO$_3$-pyridine complex. When the weight ratio of SO$_3$-pyridine complex to polysaccharide was 1:5, the degrees of sulfation were the highest at 2.75 and 2.53 respectively. The anticoagulation effect was the highest when the molecular weight was 8.0${\times}$10$^3$ Da, and the anticoagulation activity was the highest at 91% of that of heparin when sulfated chitosan and sulfated sodium alginate were mixed at a weight ratio of 1:1. The anticoagulation activity was highest at 84% of that of heparin in the active plastin trombo test (aPTT) when sulfated chitosan and sulfated sodium alginate were mixed at a weight ratio of 1:1.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.730-735
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• 2005

Possibility of using low-molecular weight alginate as a wall material for encapsulation of fish oil was investigated. Encapsulation yield increased with increasing calcium chloride concentration up to 5% and was maintained thereafter, whereas slightly increased with increasing sodium alginate concentration up to 1.25% and decreased dramatically thereafter; emulsifier concentration had no effect on encapsulation yield. Loading efficiency increased with increasing content of core material. Encapsulation yields of low- and high-molecular weight alginates were similar, indicating low-molecular weight alginate can be used as wall material for encapsulation of fish oil.

• Polymer(Korea)
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• v.35 no.5
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• pp.444-450
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• 2011

A high molecular weight natural sodium alginate (HMWSAs) was depolymerized by hydrogen peroxide ($H_2O_2$) with ultrasonic irradiation. The effects of the reaction conditions such as reaction temperature, reaction time, hydrogen peroxide concentration and ultrasonic irradiation time on the molecular weights and the end groups of the depolymerized alginates were investigated. It was revealed that depolymerization occurred through the breakage of 1,4-glycosidic bonds of sodium alginate and the formation of formate groups on the main chain under certain conditions. The changes in molecular weight were monitored by GPC-MALS. The molecular weight of 2 wt% alginate solution decreased from 450 to 15.9 kDa for 0.5 hrs at 50 $^{\circ}C$ under an appropriate ultrasonic irradiation. The PDI(polydispersity index)s of the alginate depolymerized in this study were considerably narrow in comparison with those obtained from the other chemical degradation method. The PDIs were in the range of 1.5~2.5 in any reaction conditions employed in this study.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.557-562
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• 2018

High molecular weight sodium alginate (HMWSA)/low molecular weight sodium alginate (LMWSA) microcapsules containing phytoncide oil were prepared with different LMWSA contents. The effects of the stirring rate and ratio of HMWSA/LMWSA on the diameter and morphology of the phytoncide/alginate beads were investigated by optical microscopy and the release behaviors of phytoncide oil from the phytoncide/alginate beads were characterized by UV/Vis. spectrophotometry. The mean particle size of the phytoncide/alginate beads decreased with increasing stirring rate and concentration of the calcium chloride solution. The surface morphology of the phytoncide/alginate beads changed from smooth surfaces to skin-like rough surfaces with increasing LMWSA content. These results were due mainly to the increased hydrophilic groups at the bead surface, resulting in an increase in the release rate of phytoncide oil in the phytoncide/alginate beads.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.416-422
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• 2013

In order to incorporate silver ions into the alginate, silver-alginate was prepared with aqueous solutions of silver nitrate. In the study, the silver-alginate was prepared by blending with poly vinylpyrrolidone solutions and the electrospinning was performed by using this blend solution. Antibacterial properties of silver-alginate/PVP solutions were estimated for Escherichia coli and Staphylococcus aureus by the colony counting test. Electrospinning conditions of silver-alginate/PVP solution were the tip-to-collector distance of 22 cm, the flow rate of the solution at 0.01 mL/min, and the voltage at 26 kV. The form and size of silver-alginate/PVP nanofibers were estimated by SEM and Image J. The average diameter of the electrospun SA5P15 fibers was 124 nm and showed a narrow diameter distribution. The reduction of bacteria for SA5P15 exhibited 99.9% after 24 h.