• 대한화학회지
• /
• 제33권1호
• /
• pp.46-54
• /
• 1989

식품 및 비타민 제제중에 존재하는 지용성 비타민의 추출 및 동시 정량법을 검토하였다. 역상 액체크로마토그래피에 의한 지용성 비타민의 동시 분리 및 정량은 메탄올 : 물 = 95 : 5 이동상으로 Novapak $C_{18}$ 컬럼하에서 이루어졌다. 비타민의 검출에는 UV검출기를 사용하였으며 검출감도를 증가시키기 위하여 분석중 UV 검출파장을 각각의 비타민 용리시간에 따라 최대흡수 파장인 330, 265, 285 및 290nm로 변경하였다. 지용성 비타민의 분리 및 분석은 40분안에 완료되었다. 시료의 전처리에는 알카리 가수분해법과 효소가수분해법을 이용하였으며, 비타민의 추출은 액체-액체추출법과 액체-고체추출법을 이용하였다. 비타민 A,D, E 분석에는 알카리 가수분해법 및 효소가수분해법이 비타민 K 분석에는 효소가수분해법만이 좋은 결과를 나타냈으며, 비타민 추출에는 액체-액체 추출시 diethyl ether, pentane 및 n-hexane이, 액체-고체 추출시 silica 카트리지가 좋은 추출효과를 나타냈다.

• 분석과학
• /
• 제32권5호
• /
• pp.163-172
• /
• 2019

Methamphetamine (MA) is currently the most abused illicit drug in Korea and its major metabolite is amphetamine (AP). As MA exist as two enantiomers with the different pharmacological properties, it is necessary to determine their respective amounts in a sample. Thus a chiral stationary phase liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for identification and quantification of d-MA, l-MA, d-AP, and l-AP in human urine. Urine sample ($200{\mu}L$) was diluted with pure water and purified using solid-phase extraction (SPE) cartridge. A $5-{\mu}L$ aliquot of SPE treated sample solution was injected into LC-MS/MS system. Chiral separation was carried out on the Astec Chirobiotic V2 column with an isocratic elution for each enantiomer. Identification and quantification of enantiomeric MA and AP was performed using multiple reaction monitoring (MRM) detection mode. Linear regression with a $1/x^2$ as the weighting factor was applied to generate a calibration curve. The linear ranges were 25-1000 ng/mL for all compounds. The intra- and inter-day precisions were within 3.6 %, while the intra- and inter-day accuracies ranged from -5.4 % to 11.8 %. The limits of detection were 2.5 ng/mL (d-MA), 3.5 ng/mL (l-MA), 7.5 ng/mL (d-AP), and 7.5 ng/mL (l-AP). Method validation parameters such as selectivity, matrix effect, and stability were evaluated and met acceptance criteria. The applicability of the method was tested by the analysis of genuine forensic urine samples from drug abusers. d-MA is the most common compound found in urine and mainly used by abusers.

• 분석과학
• /
• 제34권5호
• /
• pp.212-224
• /
• 2021

The intent of the present work was to develop a simple, sensitive, accurate, precise, rapid and economical UV- spectrophotometric and reverse phase high pressure liquid chromatographic method for the simultaneous estimation of Spironolactone and Furosemide in bulk and combined tablet dosage forms. UV-Spectrophotometry was carried out by simultaneous equation method using 0.02 M potassium dihydrogen phosphate buffer pH 3.5: Acetonitrile (50:50) v/v as a solvent. The linearity range was 2-14 ㎍ mL^-1 for Spironolactone and Furosemide with a correlation coefficient > 0.99. The chromatographic separation was achieved on 250 mm × 4.6 mm, hypersil BDS C18 column with particle size 5 ㎛, by using an isocratic mixture of 0.02 M potassium dihydrogen phosphate buffer pH 3.5: Acetonitrile: tert butyl methyl ether (49:50:1) v/v/v as a solvent at a flow rate of 1 mL min^-1 and UV detection was carried out at 254 nm. The retention time were observed to be 3.666 and 6.661 minutes for Furosemide and Spironolactone respectively. The two developed methods were validated according to the ICH guidelines for accuracy, precision, linearity, LOD, LOQ and were found to be within the limits. It can be concluded that these two methods could be successfully used for the simultaneous estimation of Spironolactone and Furosemide in bulk and combined tablet dosage forms.

• 생약학회지
• /
• 제45권1호
• /
• pp.84-87
• /
• 2014

A high performance liquid chromatography (HPLC) method for the quantitation of ellagic acid in Nymphaea tetragona was developed for the quality control of functional cosmetic ingredient, the extract of N. tetragona. Separation and quantitation were successfully achieved with a Kromasil C18 column ($5{\mu}m$, $250mm{\times}4.6mm$, i.d.) by isocratic elution of a mixture of acetonitrile containing 0.1% trifluoroacetic acid and water containing 0.03% phosphoric acid at a flow rate of 1.0 ml/min. The UV detector was used for the detection and the wavelength for quantitation was set at 254 nm. The presence of ellagic acid in the extract was determined by comparison of retention time and spiking with authentic standard. Analytical results showed good linearity ($R^2=0.99996$) in relatively wide concentration ranges. The R.S.D. for precision test was less than 3.0%. Recovery of the compound was 98.55~101.72% with R.S.D values less than 4.0%. In conclusion, this method has been successfully applied to the determination of ellagic acid in N. tetragona.

• Journal of Pharmaceutical Investigation
• /
• 제41권5호
• /
• pp.289-294
• /
• 2011

A rapid and specific high performance liquid chromatography-tandem mass (LC/MS/MS) method for the analysis of montelukast in human plasma has been developed and validated. After cold acetonitrile-induced precipitation of the plasma samples, montelukast and glipizide (internal standard, IS) were eluted on a reverse-phase $C_{18}$ column by isocratic mobile phase consisted of 10 mM ammonium formate buffer (adjusted to pH 3.5 with formic acid) and acetonitrile (3:97, v/v). Acquisition was performed with multiple reaction monitoring (MRM) mode by monitoring the transitions: m/z 587.2${\rightarrow}$ 423.2 for montelukast and m/z 446.0${\rightarrow}$321.2 for IS. Ranges of concentration for calibration curves (10-1000 ng/mL) showed correlation coefficients ($r^2$) were better than 0.9948. Precision of intra- and inter-day ranged from 3.70 to 11.68% and from 3.04 to 12.95%, accuracy of intra-day and inter-day ranged from 93.34 to 102.75% and from 100.79 to 107.63%, respectively. The described method provides a fast and sensitive analytical tool for determining montelukast levels in plasma, and was successfully applied to a pharmacokinetic study in 16 healthy human subjects after oral administration of 10mg tablet formulation of montelukast sodium under fasting conditions.

• 약학회지
• /
• 제52권2호
• /
• pp.93-100
• /
• 2008

A liquid chromatographic method with tandom spectrometric detection (LC/MS/MS) for the simultaneous determination of doxifluridine and its active metabolite, 5-fluorouracil (5-FU) was developed over the concentration range of $5{\sim}2000$ ng/ml, respectively. Doxifluridine, 5-FU and internal standard, 5-chlorouracil (5-CU), were extracted from liver and intestine tissue via protein precipitation. Acetonitrile was used as the extraction solvent and the supernatant was evaporated and reconstructed in mobile phase. Optimum chromatographic separation was achieved on a Agilent Zorbax $C_{18}$ ($100\;mm{\times}2.1\;mm$, $3.5\;{\mu}m$) column with mobile phase run in isocratic with methanol : water (20 : 80, v/v). The flow rate was 0.2 ml/min with total cycle time of 5 min. The lower limit of quantification was validated at 5.0 ng/ml of liver and intestine tissue, for both doxifluridine and 5-FU, respectively. The intra-day and inter-day precision and accuracy of quality control (QC) samples were <11% coefficient of variation and <7% relative error from theoretical concentration for both analytes. In addition, the special designed stability study was performed, because the metabolism of doxifluridine occurs spontaneously even in ice bath for monkey liver. The stability of doxifluridine in liver and intestine of monkey and beagle dog was compared. It was found that bioanalytical validation could not be performed for the monkey liver; however, beagle dog's liver has relatively low speed of metabolism compared to monkey liver and instead of monkey liver, beagle dog's liver could be used for the validation. Bioanalytical validation could be performed in monkey intestine. Eventually, this developed method for liver and intestine will be useful in support of the toxicokinetic and pharmacokinetic studies of doxifluridine and 5-FU.

• 한국식품영양과학회지
• /
• 제33권9호
• /
• pp.1584-1587
• /
• 2004

해안가 및 폐염전 등에 서식하며 각종 미네랄, 아미노산 및 유용 생리활성 물질을 함유하고 있는 함초로부터 혈중 동맥경화 및 심장 질환 예방에 유효한 효능을 보일 것으로 예상되는 성분인 betaine을 HPLC를 이용하여 분석하였다. 함초는 양쪽성 물질로 같이 존재하는 다른 이온성 물질들에 의해 방해를 받으며 UV 흡수가 매우 낮아 일반적인 정량방법으로는 분석이 매우 까다롭다. 따라서 본 연구에서는 이러한 문제를 해소하기 위하여 2단계 이온교환수지 컬럼을 이용하여 방해물질을 제거한 후 betaine을 4-bromophenacyl bromide (PBPB)로 유도체화시켜 UV-labelling 한 후 분석하였다. 이온교환수지를 통과한 함초추출물의 회수율은 83.6%이며 함초추출액 mL당 4.85mg의 betaine이 함유되어 있는 것으로 나타났다.

• Journal of Pharmaceutical Investigation
• /
• 제41권5호
• /
• pp.309-315
• /
• 2011

A sensitive and specific liquid chromatographic method coupled with tandem mass spectrometry (LC-MS/MS) was developed for the analysis of ambroxol (active moiety of acebrophylline). After acetonitrile precipitation of proteins from plasma samples, ambroxol and the domperidone (internal standard, IS) were eluted on a C18 column. The isocratic mobile phase was consisted of 10 mM ammonium acetate and methanol (10 : 90, v/v), with flow rate at 0.2 mL/min. A tandem mass spectrometer, as detector, was used for quantitative analysis in positive mode by a multiple reaction monitoring mode to monitor the m/z 379.2${\rightarrow}$264.0 and the m/z 426.2${\rightarrow}$175.1 transitions for ambroxol and the IS, respectively. Twenty four healthy Korean male subjects received two capsules (100 mg ${\times}$ 2) of either the test or the reference formulation of acebrophylline HCl in a 2 ${\times}$ 2 crossover study, this was followed by a 1week washout period between either formulation. $AUC_{0-t}$ (the area under the plasma concentration-time curve) was calculated by the linear trapezoidal rule. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. The 90% confidence intervals for the log transformed data were acceptable range of log 0.8 to log 1.25 (e.g., log 0.8964 - log 0.9910 for $AUC_{0-t}$ log 0.8690 - log 1.0750 for $C_{max}$). The major parameters, $AUC_{0-t}$ and $C_{max}$ met the criteria of Korea Food and Drug Administration for bioequivalence indicating that Acephyll$^{(R)}$ capsule (test) is bioequivalent to Surfolase$^{(R)}$ capsule (reference).

• Applied Biological Chemistry
• /
• 제36권4호
• /
• pp.310-314
• /
• 1993

HPLC를 이용하여 fructose oligomer인 fructo올리고당(GF2-GF7) 및 inulo올리고당(F2-F4)의 분리, 정량을 실시하였다. TSK-gel amide 80 column과 acetonitrile-water(65:35; v/v) 용매를 사용하여 각 표준당들을 효과적으로 분리할 수 있었으며 이들의 retention time은 분석시마다 거의 변하지않아 재현성이 있었다. 각 당의 농도에 따른 peak면적을 이용하여 표준곡선을 작성한 결과 넓은 당량의 범위에 걸쳐 결정계수가 0.9884이상의 값을 보여 본 HPLC방법에 의한 정량법이 타당한 것으로 나타났다. 또한 기울기는 비슷하나 y축 절편 값이 당마다 크게 상이하여 몇가지 표준당들을 기준으로 하여 모든 당을 일률적으로 정량하는 것은 적합하지 않으며 각 당에 대한 표준곡선을 하나씩 작성하여 정량하여야함을 알 수 있었다.

• Natural Product Sciences
• /
• 제15권1호
• /
• pp.50-54
• /
• 2009

A simple and reliable reversed phase HPLC method was developed to determine pharmacologically active compounds ent-continentalic acid, kaurenoic acid, and continentalic acid from the roots of Aralia cordata. Quantitative analysis of diterpenoids of A. cordata were performed by reverse phase C-18 column using a isocratic of acetonitrile : 0.1% trifluoroacetic acid(70:30) with UV detection at 205 nm. The correlation coefficients of each calibration curve of ent-continentalic acid, kaurenoic acid, and continentalic acid were 0.9987, 0.9983, and 0.9986, respectively. The detection limit of ent-continentalic acid, kaurenoic acid, and continentalic acid were $0.5{\sim}1.0\;{\mu}g/mL$, respectively. The contents of ent-continentalic acid (1), kaurenoic acid (2), and continentalic acid (3) of the roots of A. cordata collected from seventeen district markets in Korea were $0.09{\sim}0.75\;mg/g$, $1.09{\sim}5.43\;mg/g$, and $2.69{\sim}9.08\;mg/g$, respectively.