• Polymer(Korea)
• /
• v.26 no.2
• /
• pp.279-286
• /
• 2002

For surface modification of polymers with hydrophilic functional groups, acrylic acid was grafted and immobilized on the surface of polyethylene(PE) by cold-plasma treatment using Ar gas. The modifications were identified by analysis of ATR-IR spectrum and by the measurement of contact angles. Compared to virgin PE significant decreases in contact angle were observed for both the grafted PE and the immobilized PE. The decreases of contact angle were in the range of 47~$53^{\circ}$ for grafted PE and 23~$26^{\circ}$ for immobilized PE. The degree of hydrophilicity depended strongly on the plasma-treating time and discharge power. For the case of grafting it has show that the longer plasma-treating time, the higher hydrophilic character. For the case of immobilization, whereas, higher discharge power and longer exposure to plasma have shown the detrimental effect for the preparation of hydrophilic PE surface due to the decrease of carboxyl group by ablation effect. The decrease in adhesion strength of immobilized PE. compared to grafted PE, was also attributed to the ablation of carboxyl group.

• Polymer(Korea)
• /
• v.26 no.1
• /
• pp.28-36
• /
• 2002

In this study, we synthesized novel thiophene derivatives by the protection of the carboxyl group of 3-thiophene acetic acid with differently substituted benzyl groups. While 3-thiophene acetic acid is not electro-polymerizable, the modified monomers can be easily electro-oxidized to form stable electroactive polymers. The protecting groups can be easily removed in the solid state and the desired reactive carboxyl group can be introduced on the polymer surface. SEM observations show that obtained polymer films show a very good film surface and homogeneous morphology on the Pt electrode. After introduction of macromonomer, FT-IR spectrum shows new absorption bands at 1650 and $1550 cm^{-1}$, which is consistent with the formation of an amide bond. Electroactivity measurements were examined by cyclic voltammogram(CV). These polymers showed the characteristic electrochemical behavior of poly(3-alkylthiophene)s with reversible redox transition in the range of 0.7-0.9 V.

• Korea Journal of Cosmetic Science
• /
• v.2 no.1
• /
• pp.11-19
• /
• 2020

The aim of this study is to investigate the effect of various pentapeptides on hair repair depending on the characteristics of comprising amino acids using crosslinking agents in hair. Total ten peptides were synthesized with two kinds of amino acids respectively, of which were previously categorized according to R group of the amino acids contributing to the characteristic of each peptide: STTSS (Ser-Thr-Thr-Ser-Ser), LIILL (Leu-Ile-Ile-Leu-Leu), CMMCC (Cys-Met-Met-Cys-Cys), DEEDD (Asp-Glu-Glu-Asp-Asp), RKKRR (Arg-Lys-Lys-Arg-Arg), TAMRA-STTSS, TAMRA-LIILL, TAMRA-CMMCC, TAMRA-DEEDD, and TAMRA-RKKRR. Pentapeptide alone, or pentapeptides with crosslinking agents such as polymeric carbodiimide (PCI) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) were treated to chemically damaged hair. Hair diameter and break strength (N = 40/case) were measured to calculate tensile strength of hair for computing hair repair ratio, and fluorescence yields (N = 20/case) were collected for hair treated with TAMRA-peptides. The tensile strength of hair treated with pentapeptides alone, or pentapeptides with cross-linking agents is consistent with the fluorescence yield from the microscope images of the cross-sectioned hair in vision and in numerical values. Pentapeptides consisting of hydrophobic amino acids (LIILL), amino acids with sulfur (CMMCC), and basic amino acids (RKKRR) increased the tensile strength in perm-damaged hair. Pentapeptides with no extra carboxyl/amine groups in R group of amino acids resulted in no significant differences in hair strength and fluorescence yield among hairs treated with alone and with crosslinkers. Pentapeptides with extra carboxyl groups or amine groups enabled further strengthening of hair due to increased bonds within the hair after carbodiimide coupling reaction. The hair repairs of pentapeptides with various amino acid sequences were studied using crosslinking. Depending on the physical characteristics of comprising amino acids, the restoration of damaged hair was observed with tensile strength of hair and fluorescence signals upon cross-sectioned hair in parallel to possibly understand the binding tendency of each pentapeptide within the hair.

• The Korean Journal of Physiology
• /
• v.10 no.1
• /
• pp.15-24
• /
• 1976

The action of aconite on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action of aconite on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by aconite, and the concentration of aconite for maximal activity is about 80 mg%. The pH optimum for the aconite sensitive component is 8.0. 2. The activating effect of aconite on the ATPase, with a given concentration of sodium in the medium, is increased by raising the potassium concentration but activity ratio is decreased. 3. The activating effect of aconite on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased. 4. The action of aconite on the ATPase activity is inhibited by calcium ions and the effect of inhibition is increased by small amounts of calcium but decreased by larger amounts. 5. The activating effect of aconite on the ATPase was not related to the sulfhydryl group of cysteine, the amino group of lysine, the hydroxyl group of threonine or the imidazole group of histidine. 6. The action of aconite on the ATPase activity is due to carboxyl group of the enzyme of NaK ATPase.

• The Korean Journal of Physiology
• /
• v.8 no.1
• /
• pp.67-76
• /
• 1974

The effect of saponin on the sodium plus potassium activated ATPase activity was studied in the rabbit red cell ghosts and the experiments were also designed to determine the mechanism of action of saponin on the APTase activity. The following results were observed. 1. The ATPase activity of rabbit red cell ghosts is inhibited by low concentration of saponin but increased by high concentration. The activating effect of saponin on the $Na^{+}-K^{+}-ATPase$ activity is inhibited by ouabain but the stimulation of the $Mg^{++}-ATPase$ by high concentration of saponin is not inhibited by ouabain. 2. The activity ratio of $Na^{+}-K^{+}-ATPase$ by high concentration of saponin is decreased by raising the potassium concentration, and is increased by raising the sodium concentration. 3. The ATPase activity is increased by small amounts of calcium but inhibited by larger amounts. The activity ratio of the enzyme by saponin is decreased by raising the calcium concertration 4. The action on the ATPase activity was not related to the amino group of lysine, the hydroxyl group of threonine, the imidazole group of histidine, or the carboxyl group of aspartic acid. 5. The action of saponin on the ATPase activity is due to sulfhydryl group of the enzyme of $Na^{+}-K^{+}-ATPase$.

• The Korean Journal of Physiology
• /
• v.12 no.1_2
• /
• pp.25-34
• /
• 1978

The action of theobromine on the sodium plus potassium activated ATPase activity In the rabbit red cell membrane has teen investigated and the experiments were also designed to determine the mechanism of action of theobromine on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red fell membrane is stimulated by theobromine, and the concentration of theobromine for maximal activity is about 3mM. 2. The activating effect of theobromine on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased. 3. The activating effect of theobromine on the ATPase, with a given concentration of sodium in the medium. is increased by the raising the potassium concentration but activity ratio is decreased. 4. The NaK ATPase activity is increased by small amounts of calcium but decreased by larger amounts. The activity of the enzyme by theobromine is increased by small amounts of calcium but decreased by larger amounts. 5. The activating effect of theobromine on the ATPase was not related to the hydroxyl group of threonine and imidazole group of histicline. 6. The activating effect of theobromine on the ATPase is due to sulfhydryl group, amino group and carboxyl group of the enzyme of NaK ATPase.

• The Korean Journal of Physiology
• /
• v.11 no.1
• /
• pp.11-20
• /
• 1977

The action of pilocarpine on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action of pilocarpine on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by pilocarpine, and the concentration of pilocarpine for maximal activity is about 3 mM. The pH optimum for the pilocarpine sensitive component is 8.0. 2. The activating effect of pilocarpine on the ATPase, with a given concentration of sodium .in the medium, is increased by raising the potassium concentration but activity ratio is decreased 3. The activating effect of pilocarpine on the ATPase, with a given concentration of Potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased 4. The NaK ATPase activity is increased by small amounts of calcium but decreased by 'larger amounts. The activity ratio of the enzyme by pilocarpine is decreased by small amounts .of calcium but decreased by larger amounts. 5. The activating effect of pilocarpine on the ATPase was not related to the sulfhydryl group of cysteine, the hydroxyl group of threonine or the imidazole group of histidine. 6. The activating effect of pilocarpine on the ATPase is due to amino group and carboxyl group of the enzyme of NaK ATPase

• The Korean Journal of Physiology
• /
• v.11 no.1
• /
• pp.1-9
• /
• 1977

Action of anthraquinone on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action of anthraquinone on the ATPase activity. The following results were obtained 1. The activity of the NaK ATPase from red cell membrane is inhibited by anthraquinone and the concentration of anthraquinone for maximal inhibition is about 5mM. 2. The ratio of inhibition of NaK ATPase by anthraquinone, with a giving concentration of sodium in the medium, is increased by raising the potassium concentration. 3. The ratio of inhibition of NaK ATPase by anthraquinone, with a given concentration of potassium in the medium, is increased by raising the sodium concentration. 4. The action of anthraquinone on the NaK ATPase activity is inhibited by calcium ions and the ratio of inhibition is increased by small amounts of calcium but almost constant by larger amounts. 5. The inhibitory action of anthraquinone on the NaK ATPase activity was not related to the amino group of lysine, the hydroxyl group of threonine or the imidazole group of histidine. 6. The inhibitory action of anthraquinone on the ATPase activity is due to sulfhydryl group or the carboxyl group of the enzyme of NaK ATPase.

• 한국생물공학회:학술대회논문집
• /
• 2003.04a
• /
• pp.635-638
• /
• 2003

For the acute assessment on biological toxicity of wastewater, surface plasmon resonance(SPR) based cell viability detection was performed using gold surface-confined cell as a result of adhesion-modifying chemicals. Escherichia coli O157:H7 (E. coli O157:H7) was investigated after exposure to EDTA. Cells were immobilized on gold coated slide glass for SPR analysis by the method of cross-linking carboxyl group on the bacterial surface with amine group of poly-L-lysine that had been coupled to the gold surface modified by a self-assembled monolayer of 11-mercaptounde canoic acid (11-(MUA)). Reflective intensity of each flow step was changed with respect to confect of ethylenediaminetetraacetic acid (EDTA) disodium salt and phosphate-buffered saline (PBS) solution. The proposed detection technique can be used for biological toxicity test.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.30 no.2
• /
• pp.55-61
• /
• 1998

This treatment was applied to bleached softwood kraft pulp handsheets in an effort to improve physical strength of paper. Paper strength was improved by esterification of cellulose and polycarboxylic acid. Because hydrogen bond of carboxyl group is stronger than that of hydroxyl group, polycarboxylic acid forms stronger hydrogen bond than cellulose does. 1,2,3,4,-cyclopentanetetracarboxylic acid (CPTA) and sodium dihydrogen phosphate ($NaH_2O_4$) were used as polycarboxylic acid and catalyst, respectively This reaction was confirmed by the weight gain of the handsheets, by FTIR spectrum and by changes in mechanical properties of sheets. Wet tensile strength was improved when handsheets were treated with polycarboxylic acid. However, tear strength and burst strength decreased.