• Polymer(Korea)
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• v.32 no.6
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• pp.561-565
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• 2008

Hyaluronic acid (HA) is a natural glycosaminoglycan and is used widely in the pharmaceutical field. Lipoic acid (LA) helps the regeneration of exogenous and endogenous antioxidants such as Vitamin C and Vitamin E as well as glutathione. It also acts as antioxidant indirectly. Hydrophilic HA as a biodegradable and biocompatible polymer was conjugated with hydrophobic LA as an antioxidant to form the graft copolymer. The carboxyl group of HA was modified by adipic acid dihydrazide (ADH). The synthesis of HA-g-LA graft copolymers was characterized by FT-IR, $^1H$-NMR spectroscopy. The conjugates could form the self-assembled nanoparticles in aqueous solution. The particle size and critical aggregation concentration were verified to use the nanoparticle as a carrier fur the hydrophobic material.

• Polymer(Korea)
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• v.35 no.3
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• pp.223-227
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• 2011

Stimuli-responsive polymers have been investigated as the materials playing the critical roles in various applications. Thermoresponsive graft copolymers, poly (N-isopropylacrylamide)-g-hyaluronic acid (PNIPAAm-g-HA) and elastin-like peptide-g-hyaluronic acid (ELP-g-HA), were synthesized by coupling carboxylic polymers (PNIPAAm-COOH or ELP) to biocompatible HA through amide linkages. Thermoresponsive behavior was observed in both the copolymers, and the results of turbidity measurement were consistent with the results of rheological examination. Among the two copolymers, the ELP graft copolymer shows less cooperative LCST transition than the PNIPAAm case. As the content of graft chains of PNIPAAm and ELP increases, viscosity increases, and the increase was larger in PNIPAAm case at a graft content. These results shows us that the introduction of grafts provides thermosensitivity to biocompatible HA, whose characteristics can be engineered.

• 대한치주과학회:학술대회논문집
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• 2002.11a
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• pp.92-92
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• 2002

• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.589-602
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• 2002

Hyaluronic acid (HA)는 중요한 glycosaminoglycan 중 하나로서 단백질과 화학적 결합을 하지 않기 때문에 분리가 쉽고 결합조직의 세포간 기질의 주요 성분이다. 우리는 점탄성 고분자 hyaluronic acid를 실험실상에서 사람 태아 골모세포의 골 형성 과정에 미치는 영향을 알아보고자 하였다. 우리는 여러 농도의 HA에 대한 사람 태아 골모세포에서의 세포증식, 염기성 인산분해효소 활성, 석회화 결절 형성능, 교원질 합성능 그리고 bone sialoprotein (BSP)의 발현 정도를 검사하였다. 세포증식에서 각 농도의 HA 처리군과 대조군 간에 2일과 4일간의 결과에서 유의한 차이를 보이지 않았다. 염기성 인산분해효소 활성에서는 0.063% HA 처리군에서 음성 대조군에 비해 가장 유의한 염기성 인산분해효소 활성을 보였다 (p<0.05). 0.063% HA 처리군은 교원질 합성능에서도 가장 높은 수준을 보였다 (p<0.05). 석회화 결절 형성능에서는 0.063% HA 처리군에서 대조군에 비해 많은 염색된 석회화 결절을 보였다. BSP의 발현 정도를 분석한 Western blot에서는 대조군에 비해 0.063% HA 처리군에서 증가된 단백질 발현을 나타났다. 본 연구 결과 고분자 HA가 실험실상에서 사람 태아 골모세포의 분화를 통해 새로운 골 형성을 유도할 수 있는 능력이 있음을 시사하였다.

• The Korean Journal of Vision Science
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• v.20 no.4
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• pp.513-521
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• 2018

Purpose : : In this study, we made dopamine-functionalized hydrogels containing a cross-linked hyaluronic acid (HA) network and investigated their antioxidant activities. Methods : In the first step, we made poly hydroxyethyl methacrylate(p(HEMA))-based hydrogels post-modified with an interpenetrating polymer network(IPN) structure composed of HA polymers and a p(HEMA) network. The subsequent functionalization with dopamine via an amide coupling reaction resulted in the antioxidant hydrogels. Their antioxidant activities were evaluated using 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays. Results : The dopamine-modified hydrogels exhibited significant antioxidant activities, when compared to unmodified control. The presence of the HA-IPN structure improved the surface wettability of the hydrogel while dopamine-conjugated IPN hydrogel did not demonstrate the significant difference compared to hydrogel control. Dopamine-modified hydrogels exhibited high transmittance (>88%). Conclusion : The results demonstrate that the development of antioxidant hydrogels based on dopamine-conjugated HA-IPN structures may help develop ophthalmic and biomedical materials.

• Polymer(Korea)
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• v.35 no.2
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• pp.119-123
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• 2011

To develop hyaluronic acid (HA)-based anticancer agent carrier, hyaluronic acid was chemically modified with the hydrophobic group of deoxycholic acid(DA). The physicochemical properties of the deoxycholic acid-conjugated HA (HADA) were investigated by using $^1H$ NMR, FTIR spectrophotometer and TEM. Paclitaxel (Tx)-loaded HADA nanoparticles were prepared by a dialysis method. The loading efficiency of drug and drug contents of Tx-loaded HADA nanoparticles (HADA-Tx) were measured by HPLC. The anticancer activity of HADA-Tx was investigated by its cytotoxicity against KB cell in vitro. The HADA-Tx was shown to have the superior potential for the anticancer drug delivery.

• Journal of the Korean Society of Radiology
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• v.12 no.1
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• pp.9-16
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• 2018

Hangover after drinking is different from person to person symptoms and degree, but usually thirst, fatigue, headache, general boredom, gastrointestinal disorder, vomiting, diarrhea, deficiency of vitamin appears. This hanging phenomenon is caused by the action of precursors such as ethyl acetate and acetaldehyde, which are the by products of fermentation contained in alcohol and alcohol accumulated in hepatocytes and body. In order to solve the hangover phenomenon, the same Origin as polysaccharide Polydeoxyribonucleotide, which is a nucleic acid-sugar-phosphate complex, which is a semen or testicular extract in salmon extract, and a water soluble salmon extract powder having the same structure and lower price than Polydeoxyribonucleotide And D-Glucuronic acid and N-Acetyl glucosamine. It has excellent biocompatibility, viscoelasticity and moisturizing power. It has effect on reduction of body water loss and skin moisture content in hangover phenomenon. It is antioxidant and skin moisturizing effect Hyaluronic acid was irradiated with gamma rays, and the composition was prepared by using the salmon extract powder and the main raw material. The ethanol degradation, the acetaldehyde reduction amount, the blood acetaldehyde concentration and the acetic acid concentration were measured to evaluate the alcoholysis effect, Skin moisture evaporation rate To examine the evaluation unit water content of the skin was improved determine whether the antioxidant and provide skin moisturizing effect. The addition of ethanol extracts of salmon extracts showed a decrease of 5 to 7 times compared with no addition, and a decrease of 3 to 5 times of acetaldehyde. In addition, the change of acetaldehyde concentration and acetic acid concentration in blood showed a rapid decrease compared to the no - added control group. In addition, when the raw material of hyaluronic acid was used, skin moisture content was high and skin moisture evaporation amount was decreased. Therefore, hyaluronic acid, which is a polysaccharide polymer, has excellent viscoelasticity and moisturizing ability, It is considered to provide antioxidant and skin moisturizing effect. Therefore, it can be said that the composition containing salmon extract powder and hyaluronic acid as a main ingredient is effective for the hangover phenomenon which occurs after drinking.

• Korean Journal of Food Science and Technology
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• v.54 no.3
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• pp.327-333
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• 2022

An orally disintegrating film (ODF) based on hyaluronic acid (HA) containing vitamin D was developed. The vitamin D content in the ODF was set based on the adequate intake (AI) of vitamin D from 0 to 10 AI (0, 1, 4, 7, and 10AI). The control (0AI) had the highest thickness and showed the longest disintegration time among the samples. The moisture content of the ODFs was significantly lower in those with vitamin D compared to the control. As the amount of vitamin D increased, the water vapor permeability (WVP) of the ODFs decreased, and the opacity significantly increased. The tensile strength was higher in the films containing vitamin D compared to the control films. However, the elongation at the break showed no significant difference among the films. The vitamin D content in the film was reduced by 25.7-44.2% during processing compared to the amount that was originally added. Based on the above results, a new and convenient vitamin D delivery system, an ODF, could be successfully produced.

• Journal of radiological science and technology
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• v.37 no.1
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• pp.15-20
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• 2014

This study was to evaluate clinical feasibility of biodegradable polymeric membrane for interventional procedure in preliminary study. Bio-degradable polymetric membrane was produced into a solution by mixing hyaluronic acid powder with NaOH solution in a heating mantle. Three different concentrations of contrast media (10, 20, and 30 vol%) were added to the produced soluble powder, and vertical agitation was performed for 12 hours at a speed of 100 to 200 rpm at a room temperature. It was freeze dried for 24 hours at a temperature $80^{\circ}C$. Pressure on the freeze dried sample was exerted by a hydraulic press in order to form the freeze dried sample into a membrane. The membrane produced with varying contrast medium concentration was visually examined by a scanning electron microscope and radiographically inspected. Under the visual examination, the higher the concentration of contrast medium, the rougher the surface. Radiographic transparency was similar under all conditions of fluoroscopic radiography, simple radiography, and serial radiography. In conclusion, this preliminary study verified that bio-degradable membrane produced with hyaluronic acid was a material with clinical usability.

• Polymer(Korea)
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• v.31 no.6
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• pp.505-511
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• 2007

Poly(lactide-co-glycolide)(PLGA) and hyaluronic acid (HA) has been widely used as biocompatible scaffold materials to regenerate tissue. In this present study, we fabricated microporous PLGA and HA loaded PLGA scaffolds by a emusion freeze-drying method. In order to confirm that the release profile of cytokine or water-soluble drugs, we manufactured the granulocyte macrophage colony stimulating factor(GM-CSF) loaded PLGA and HA-PLGA scaffold. All scaffolds were characterized using scanning electron microscope(SEM), mercury porosimeter and wettability measurement. Cell proliferation and viability were assessed by a 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium-bromide (MTT) test. The porosity of HA-PLGA scaffold was greater than 95% with the total pore area of $261\;m^2/g$. The HA-FLGA scaffold exhibited well interconnected pores to allow greater cell adhesion and prolixferation. It was proven by higher cell viability in the HA-PLGA scaffold than PLGA alone. This may be due to the enhanced natural properties and higher water retention capacity of HA.