• 대한화장품학회지
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• 제24권3호
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• pp.123-128
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• 1998

Dihydroxyacetone (DHA) has been used as a self tanning agent and many emulsion formulations containing DHA have been studied. In an emulsion, many factors which have negative effect on DHP and the resultant DHA decomposition can destabilize the emulsion base. In this study, two kinds of emulsion with 5％ DHA were prepared, O/W type emulsion and Multilamellavesicle (MLV) type emulsion to compare the stabilization effects of both emulsions on the DHA. The OHA concentration was analyzed quantitatively by high performance liquid Chromatography (HPLC), also the pH and viscosity of both emulsions were measured for stability. This process was carried out over 4 months. For HPLC, a bondaclone $C_{18}$ column with a mobile phase of distilled water and UV detector were used. The results of these experiment showed that DHA is more stable in an MLV emulsion than it is in an O/W type emulsion.

• 약학회지
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• 제31권5호
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• pp.315-321
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• 1987

A high performance liquid chromatographic method was developed for the determination of glycyrrhetinic acid contained in licorice powder. Glycyrrhetinic acid which is hydrolysate of glycyrrhizin extracted from licorice powder, was determined with good result by HPLC using 2-bromoacetyltriphenylene labeling reagent. The glycyrrhetinic acids were labeled with 2-bromoacetyltriphenylene in acetonitrile using 18-crown-6-ether and KOH as a catalyst. Derivatized glycyrrhetinic acids were separated from the extracted licorice powder on a reversed-phase column (chemopak $C_{18}$) using 100% acetonitrile as a mobile phase and monitored by an UV-detector at 268nm. Linearity of calibration curve was obtained between 5 ng and 20 ng, and the lower limit of detection was 2 ng. The recovery of glycyrrhetinic acid to licorice powder was about 99.3%. This method was sensitive, reliable and useful for, determination of glycyrrhetinic acid.

• Bulletin of the Korean Chemical Society
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• 제20권10호
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• pp.1165-1171
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• 1999

The analysis of trace herbicides using the on-line SPE-HPLC system and a photochemical reaction was studied. 18 compounds of herbicides including eight triazines, six phenoxy acids and esters, and four other herbicides were examined. The on-line SPE-HPLC system developed for selection of eluting solvent improved chromatographic efficiency. The recoveries of herbicides were higher than 77%. With 100 mL tap water samples, the detection limits for all analytes were in the 0.1-2.3×10-10 M range. Detection was done by a UV or fluorescence spectrometer after photochemical reaction at the end of the column with 2W or 450W mercury lamp. Without a photochemical reaction, all compounds responded to 230 nm UV detector, but phenoxy acids and esters were weakly detected. However, with a photochemical reaction, these compounds were selectively detected at 320 nm wavelength of UV absorption and 400 nm emission of the fluorescence detectors. This method can be used for the analysis of environmental water containing herbicides at trace levels.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.202-202
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• 2006

With a modern size exclusion chromatography (SEC) column, molecular weight analysis of a polymer sample takes about 10 min. However, it is desirable to reduce the analysis time further, in particular, for high throughput measurements required in combinatorial analyses or 2D-HPLC analyses. We implemented the high temperature SEC for the purpose. By inserting a narrow bore tubing between the column and the detector, a sufficient backpressure can be maintained to prevent the mobile phase from boiling and the effluent is cooled down enough when it reaches the detector. Therefore, a normal SEC detector can be used without any modification. The SEC resolution is greatly improved at the elevated temperature at high flow rate which allows high speed operation.

• Natural Product Sciences
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• 제19권3호
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• pp.236-241
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• 2013

A high-performance liquid chromatography-diode array detector (HPLC-DAD) method was established for quantitative evaluation of nine constituents of Fraxinus rhynchophylla such as four coumarins, esculin (1), fraxin (2), esculetin (3), fraxetin (4), three lignans, syringaresinol 4,4'-O-${\beta}$-diglucoside (5), pinoresinol 4-O-${\beta}$-glucoside (6), pinoresinol (9), one secoiridoid, oleuropein (7), and one coumarinolignan, cleomiscosin C (8). The preferred chromatographic condition was obtained on Phenomenex Gemini-NX (3 ${\mu}m$, C18 110A, $150{\times}4.60$ mm) and the mobile phase was composed of water and acetonitrile using a gradient elution. The wavelength was set at 220 nm. Extraction condition of these constituents in F. rhynchophylla was also optimized through extraction time, extraction solvent and extraction method using established method. From this study, extraction at $70^{\circ}C$ with the mixture of ethanol and water for more than 12 h was suggested to be good extraction condition for these constituents. Quantitation of nine constituents in different F. rhynchophylla samples was also successfully accomplished with the newly established method.

• Journal of Preventive Veterinary Medicine
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• 제42권4호
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• pp.171-176
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• 2018

A study of the tissue depletion of florfenicol (FFC) administered orally to pigs at a dose of 0.05 kg/ton feed for 7 days was performed. Sixteen healthy cross swine were administered with FFC. Four treated animals were arbitrarily selected to be sacrificed 1, 3 and 5 days after the end of treatment. FFC residue concentrations in muscle, liver, kidney, and fat were determined using high-performance liquid chromatography (HPLC) with ultraviolet photometric detector at 230 nm. The correlation coefficient ($R^2$) of the calibration curve for florfenicol amine (FFCa) was > 0.997 and the limits of detection and quantification were 0.012 and $0.040{\mu}g/mL$, respectively. Recovery rates in swine edible tissues ranged from 79.1 to 93.5%. In the FFC-treated group, FFC residues at 3 days post-treatment were below the maximum residue limits (MRLs) in muscle, kidney and fat, and those at 5 days post-administration were below the MRLs in all edible tissues. These results suggest that the withdrawal period of FFC after the drug treatment might be 5 days, which is a sufficient amount of time for reduction of the FFC residues below the MRLs in all edible tissues.

• 한국식품위생안전성학회지
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• 제20권4호
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• pp.267-271
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• 2005

본 연구는 세포막의 구성성분으로서 인체의 신진대사에 관여하는 물질인 인지질을 정량하기 위하여 인지질의 주요성분인 포스파티딜콜린에 대해 HPLC/ELSD를 이용한 신속, 정확한 분석법을 확립하였다. HPLC의 조건은 silica column을 사용하고 헥산:이소프로판올:물-30:60:8을 유속 0.5 ml/min으로 포스파티딜콜린을 분리하였고 ELSD 검출기를 사용하여 nebulizer온도는 $60^{\circ}C$. drift tube온도는 $75^{\circ}C$, carrier gas 30 psi로 하여 20 min내에 분리하였으며 검량선은 250 ppm$\∼$1,000 ppm으로 하여 정량하였다. 시료의 회수율은 $80\%$이상으로 높게 나타났으며 정량한계는 0.15 ppm이였다. 또한 이 분석법을 이용하여 실제 유통되고 있는 레시틴제품(난황레시틴 2종, 대두레시틴8종)에 대해 인지질의 함량과 포스파티딜함량을 조사한 결과, 인지질의 함량은 각각 81.5$\∼$83.3$\%$, $66.0\∼88.0\%$로 나타났으며 포스파티딜콜린의 함량은 각각 74.8$\∼$ 8.6$\%$및 $18.7\∼62.3\%$로 난황레시틴의 함량이 높게 나타났다.

• 한국식품영양과학회지
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• 제37권1호
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• pp.124-128
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• 2008

본 연구는 DAD/UV HPLC를 이용하여 뽕잎과 오디(Morus alba L.)에 함유되어 있는 stilbenoids의 조성과 함량을 분석하고자 수행되었다. 뽕잎과 오디추출물을 DAD를 이용하여 최대흡광파장을 탐색한 결과 308 nm로 나타났으며, stilbenoids 조성이 오디에는 resveratrol, piceatannol, rhapontigenin, astringin, pterostilbene, piceid, rhaponticin, 뽕잎에는 resveratrol, rhapontigenin, pterostilbene, piceid이 함유된 것으로 나타났다. 오디와 뽕잎의 총 stilbenoids 함량은 $609.15{\pm}7.24$ mg/100 g d.w.와 $188.57{\pm}1.70$ mg/100 g d.w.였으며, rhaponticin은 오디($389.26{\pm}5.22$ mg/100 g d.w.)와 뽕잎($99.17{\pm}2.79$ mg/100 g d.w.) 모두 가장 많은 함량이 함유되어 있었다. Astringin과 piceatannol은 오디에서만 검출되었으며 vitisin A는 모두 검출되지 않았다. Piceid와 rhaponticin은 이의 비배당체인 resveratrol과 rhapontigenin보다 과량 함유되어 있어 비배당체보다는 배당체의 함량이 높은 것으로 나타났다.

• 분석과학
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• 제26권2호
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• pp.142-153
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• 2013

Milbemycin계 속효성 살충제인 lepimectin의 국내 잔류허용기준이 신설 고시됨에 따라 농산물 중 lepimectin 잔류량을 측정하기 위해 고성능 액체크로마토그래프를 이용한 신속, 정확한 분석법을 개발하였다. Lepimectin 잔류물은 메탄올로 추출하여 포화식염수와 디클로로메탄을 이용한 액액분배를 수행하였고, 플로리실로 충진한 유리칼럼 및 아미노프로필 카트리지를 이용하여 두 번의 정제 과정을 거친 후 HPLC-PAD (High performance liquid chromatograph-photodiode array detector)를 통해 기기분석을 수행하였으며, LC-MS (Liquid Chromatograph-Mass Spectrometer)로 재확인하였다. Lepimectin 표준품의 직선성은 lepimectin $A_3$, $A_4$ 모두에서 상관계수($R^2$)가 0.9999로 우수하였다. 개발한 분석법으로 오이, 고추, 현미, 감귤, 감자, 대두에 대한 lepimectin의 회수율을 측정한 결과, 76.0~114.8% 범위로 10% 미만의 표준오차를 나타내었으며, 분석법의 검출한계는 0.005 mg/kg, 정량한계는 0.01 mg/kg이었다. 또한 광주지방식약청, 대전지방식약청의 분석법 검증 결과, 각각 70.3~108.8%, 80.5~95.6%의 회수율과 10% 미만의 표준 오차를 나타내었다. 분석법에 대한 각 실험실의 회수율과 표준오차 및 실험실간 표준 오차($RSD_R$; Relative Standard Deviation on Reproducibility)는 코덱스 기준(CAC/GL 40)에 적합함을 확인하였다. 따라서 본 연구에서 개발된 분석법은 lepimecin 잔류물의 안전관리를 위한 최적의 분석법으로 판단된다.

• 한국식품위생안전성학회지
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• 제32권5호
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• pp.404-410
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• 2017

HPLC-size-exclusion chromatography에 의해 가공식품에서 알긴산프로필렌글리콜의 함량을 분석하는 방법이 개발되었다. 알긴산프로필렌글리콜을 분석하기 위해 GF-7M HQ column과 LT-ELSD detector가 선정되었다. 알긴산프로필렌글리콜 분석을 위한 전처리 조건으로는 $20^{\circ}C$에서 150 rpm으로 3시간 동안 추출하는 방법이 선정되었다. 알긴산프로필렌글리콜을 5 농도(300, 500, 700, 1,000, and 1,500 mg/kg) 범위에서 검량선을 작성한 결과 직선성($R^2$)은 0.9873으로 측정되었다. HPLC system에 의한 알긴산프로필렌글리콜 분석시 검출한계(LOD) 및 정량한계(LOQ)는 각각 171.43 mg/kg 및 519.50 mg/kg이었다. Size-exclusion chromatography에 의해 얻은 회수율 및 변동 계수(coefficient of variation)는 각각 86.1~110.4% 및 4.1~13.5%이었다. 본 연구에서 개발된 HPLC-size-exclusion chromatography system을 적용하여 134 품목의 가공식품에서 알긴산프로필렌글리콜 함량을 분석하였다. 이 결과들은 이 방법이 가공식품에서 알긴산프로필렌글리콜 함량을 분석하는데 적용할 수 있는 방법이라는 것을 나타낸다.