• Journal of Periodontal and Implant Science
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• v.24 no.2
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• pp.433-440
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• 1994

The purpose of this investigation was to study the efficacy and safety of 6% hydrogen peroxide gel as a daily home tooth bleaching gel. The subjects consisted of 20 male dental students representing a variety of acquired stain and each subject participated for a 4-week period. Tooth color analysis(Shade determination), sulcus bleeding index, probing depth and probing attachment level were done and recorded at baseline and at the end of each week of study. The results indicated that home bleaching gel containing 6% hydrogen peroxide was effective and caused no gingival inflammation. Sulcus bleeding index, probing depth and probing attachment level showed no change. In conclusion, 6% hydrogen peroxide gel is an effective and safe agent for daily home tooth bleaching.

• Analytical Science and Technology
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• v.12 no.2
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• pp.125-129
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• 1999

Portable-type two electrode system for the determination of highly concentrated hydrogen peroxide (10-75%) has been studied. The electrode body was made with teflon rod (length=10 cm, diameter=1.5 cm) to withstand the highly corrosive power of hydrogen peroxide. Glass carbon rod (diameter=3 mm) was used as the working electrode and a carbon cylinder (i.d.=5 mm; o.d.=9 mm) was used as counter electrode. The applied voltage for the determination of $H_2O_2$ was 0.8 V. Diluting the highly concentrated samples taken from the industrial batch to 10% or less, it was possible to make quantitative determinations, while eliminating the interference from the stabilizer contained in the sample and preventing the surface of the electrode from oxidative corrosion. Employing hydrogen peroxide permeable membrane (teflon membrane${\leq}100{\mu}m$) for the electrode system, it was possible to measure the content of $H_2O_2$ in highly concentrated samples directly, quantitatively and reproducibly with no extra dilution step. However, it was necessary to change the internal electrolyte frequently to maintain the analytical performance of the electrode.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.10-12
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• 1957

On the performance of the hydrogen peroxide method for Th-determination we encountered some difficulties, namely the formation of the insoluble matter occured in the nearly neutral solution after evaporation. We carried out the Th-determination in the mixture of the Th and some kind of the rare earth, and found that the insoluble matter was not formed in case of the mixture of Th and some kind of rare earth, but formed in case of Monazite. The formation of the insoluble matter in the case of Monazite sand, however, could be avoid by using the beaker instead of the evaporating dish and by adding the water repeatedly before it was completely evaporated to dryness.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.13-14
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• 1957

Th-determination by the sebacic acid method was compared with the hydrogen peroxide method. The former is a little more complicated than the latter in the operation and at the same time it requires careful pH adjustment, but the time needed for determination could be decreased greatly by the former. As a result of the comparison between both methods we confirmed that, within ${\pm}$0.08 ${\%}$ of error, when $ThO_2$ was contained $5{\%}$ in the sample, we could use the sebacic acid method with an half time of that required for the hydrogen peroxide method. Thorium in Monazite sand was also determined by both methods and compared. In the case we found, too, that if we permitted the maximum error of ${\pm}$0.08 ${\%}$, we could prefer the sebacic acid method.

• Applied Chemistry for Engineering
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• v.28 no.3
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• pp.369-374
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• 2017

The curtailment of production cost is important for the mass production of biosensors. Since horseradish peroxidase, which is a key material of enzyme electrodes for hydrogen peroxide analysis is rather expensive, this has been a limiting factor for fabricating carbon paste based enzyme electrodes. In this paper, the acacia leaf tissue as a zymogen easily obtainable in our living environment was used as an alternative to horseradish peroxidase for developing a hydrogen peroxide sensor and the electrochemical properties were evaluated. Ten or more electrochemical parameters alongside the other experimental results acquired by the potentiostatic method demonstrated that our enzyme electrodes can be used for the quantitative analysis of hydrogen peroxide. This also indicates that acacia leaves can take the place of the marketed peroxidase.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2979-2983
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• 2009

Nanowires of polytetrakis(o-aminophenyl)porphyrin (PTAPPNW) were fabricated by electrochemical polymerization with the cyclic voltammetric method in anodic aluminum oxide (AAO) membranes. The glassy carbon electrode (GCE) modified by PTAPPNW, single-walled carbon nanotubes (SWNT) and Nafion as a binder was investigated with voltammetric methods in a phosphate buffer saline (PBS) solution at pH 7.4. The PTAPPNW + SWNT + Nafion/GCE exhibited strongly enhanced voltammetric and amperometric sensitivity towards hydrogen peroxide ($H_2O_2$), which shortened the response time and enhanced the sensitivity for $H_2O_2$ determination at an applied potential of 0.0 V by amperometric method. The PTAPPNW + SWNT + Nafion/GCE can be used to monitor $H_2O_2$ at very low concentrations in biological pH as an efficient electrochemical $H_2O_2$ sensor.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1583-1588
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• 2010

A single step fabrication process of carbon nanotube/Prussian Blue (CNT/PB) paste electrodes based on screen printing technology has been studied as an amperometric sensor for the determination of hydrogen peroxide and free chlorine. Compared to the classical carbon paste (CP) electrode, the CNT paste electrode greatly enhanced the response in the presence of hydrogen peroxide due to the electrocatalytic activity of the CNT. Based on the CNT/binder paste, PB was also incorporated into a network of CNT paste and characterized. The best electroanalytical properties of PB-mixed sensors to hydrogen peroxide were obtained with PB ratio of 10 wt % composition, which showed fast response time ($t_{90}{\leq}5$ s; 0.2 - 0.3 mM), low detection limit of 1.0 ${\mu}M$, good linear response in the range from $5.0{\times}10^{-5}$ - $1.0{\times}10^{-3}$ mol $L^{-1}$ ($r^2$ = 0.9998), and high sensitivity of -8.21 ${\mu}AmM^{-1}$. In order to confirm the enhanced electrochemical properties of CNT/PB electrode, the sensor was further applied for the determination of chlorine in water, which exhibited a linear response behavior in the range of 50 - 2000 ppb for chlorine with a slope of 1.10 ${\mu}Appm^{-1}$ ($r^2$ = 9971).

• Journal of the Korean Chemical Society
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• v.48 no.5
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• pp.491-498
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• 2004

The response characteristics of the bioelectrode developed by the co-immobilization of black goat liver tissue and ferrocene in a carbon paste matrix for the amperometric determination of hydrogen peroxide were evaluated. In the range of electrode potential examined ($-0.3{\sim}+0.0\;V$ vs. Ag/AgCl), the response time was relatively short (t95%=12 s) and it responded in the wide range of pH. The detection limit was 2.25${\times)10^{-6}M$ and a relative standard deviation of the measurements which were repeated 15 times using 1.0${\times}10^{-2 }$M hydrogen peroxide was 1.87%. The bioelectrode sensitivity decreased to 50% of the original value in 19 days of continuous use.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.3
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• pp.205-209
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• 2012

The objective of the present study was to establish the method of measurement of hydrogen peroxide and to estimate the anti-oxidative effect of genistein in the skin. UVB induced skin oxidation and anti-oxidative effect of genistein formulations were evaluated by determining levels of hydrogen peroxide. The mechanism involved in the determination of hydrogen peroxide is based on a color reaction between ferric ion ($Fe^{3+}$) and xylenol orange, often called FOX assay and subsequent monitoring of absorbance values of the reactant at 540 nm. The reaction was to some extent pH-dependent and detection sensitivity was greatest at pH 1.75. Genistein liposomal gel demonstrated better anti-oxidative effect with regard to lowering hydrogen peroxide levels elevated by UVB irradiation compared to genistein-suspended gel. A linear relationship has been observed between anti-oxidative effect of genistein and drug deposition in the skin tissue. Genistein liposomal gel resulting in the localization of the drug in the deeper skin led to improved anti-oxidative effect compared to genistein gel. The suggested method for evaluation of oxidation of the skin can be used as a tool to screen effective anti-oxidative agents and their delivery systems acting on the skin.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.998-1001
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• 2002

Micro-LC method for the quantitative determination of hydrogen peroxide in foods has been established. This method was carried out on cation-exchange resin gel column using distilled water as mobile phase with 50 mM sodium sulfate as electrolyte. The detection was performed with an electrochemical detector (ECD) at 0.6 voltage. Under this analytical condition, the recovery rates of hydrogen peroxide in tomato and lemon were 98.3 and 97.4%, respectively. Among 28 food types, hydrogen peroxide concentrations were 0.6, 0.5, 1.9, 0.9, 0.5, 0.6, 0.9, 0.8, and 0.4 ppm in banana, peach, orange, strawberry, pepper, onion, cucumber, burdock, and egg plant, respectively, Whereas none was detected in remaing 19 samples.