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

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권7호
• /
• pp.3265-3270
• /
• 2012

Clinically, elevated cancer antigen 125 (CA-125) in blood predicts tumor burden in a woman's body, especially in the ovary, but cannot differentiate between malignant or benign. We here used intensive modern proteomic approaches to identify predictive proteins in the serum of women with elevated CA-125 to differentiate malignant from benign ovarian tumors. We identified differentially expressed proteins in serum samples of ovarian cancer (OC) patients, benign ovarian tumor (BT) patients, and healthy control women using mass spectrometry-based quantitative proteomics. Both the OC and BT patients had elevated CA-125. Quantitation was achieved using isobaric tags for relative and absolute quantitation. We obtained 124 quantified differential serum proteins in OC compared with BT. Two proteins, apolipoprotein A-4 (APOA4) and natural resistance-associated macrophage 1, were verified using Western blotting. Proteome profiling applied to OC cases identified several differential serum proteins in the serum of women with elevated CA-125. A novel protein, APOA4, has the potential to be a marker for malignant tumor differentiation in the serum of women with elevated CA-125.

• Journal of Microbiology and Biotechnology
• /
• 제28권7호
• /
• pp.1141-1146
• /
• 2018

2'-Fucosyllactose (2'-FL) is one of the most important human milk oligosaccharides and has several health benefits for infants. The levels of 2'-FL in breast milk or samples from other sources can be quantified by high-performance liquid chromatography. However, this method cannot be used for simultaneous detection of the target compound in numerous samples. Here, we developed a simple method for quantifying 2'-FL in a microplate format. The method involves two steps: (i) release of $\text\tiny{L}$-fucose from 2'-FL by ${\alpha}$-(1-2,3,4,6)-$\text\tiny{L}$-fucosidase and (ii) measurement of NADPH formed during the oxidation of $\text\tiny{L}$-fucose by $\text\tiny{L}$-fucose dehydrogenase. This method enables measurement of up to 5 g/l 2'-FL in 50 min using a 96-well microplate. The efficiency and simplicity of the proposed method make it suitable for the analyses of a large number of samples simultaneously.

• 대한수의학회지
• /
• 제13권1호
• /
• pp.23-30
• /
• 1973

Thin layer, paper and column chromatography were compared for the separation, detection and quantitation of three kinds of estrogen in urine of dairy cows. While thin layer chromatography utilizing silica gel was better for the detection of estrogens, column chromatography using celite 545 was preferable. Spectrophotometry was compared with fluorometry for determination of estrone, estradiol-17 ${\beta}$ and estriol eluted by paper chromatography and column chromatography. Optical density of three standard estrogens showed almost same curve at maximum absorption wave length of 230 and $282m{\mu}$. However, the former showed a higher peak. In fluorometry, the fluorescence intensity of estrone and estradiol-17 ${\beta}$ were rather strong, when the estrogens were dissolved in sulfuric acid, and showed higher sensitivity than that of the spectrophotometry. However, in the case of estriol was exceptional.

• Bulletin of the Korean Chemical Society
• /
• 제33권7호
• /
• pp.2163-2167
• /
• 2012

A rapid, specific, and reliable LC-MS/MS-based bioanalytical method was developed and validated in rat plasma for the simultaneous quantitation of amitriptyline and its metabolite nortriptyline. Chromatographic separation of these analytes was achieved on a Gemini C18 column ($50{\times}4.60mm$, $5{\mu}m$) using reversed-phase chromatography. The mobile phase was an isocratic solvent system consisting of 1% formic acid in water and methanol (10:90, v/v), at a flow rate of 0.2 mL/min. The analytical range was set as 0.1-500 ng/mL for amitriptyline and 0.08-500 ng/mL for nortriptyline using a $200{\mu}L$ plasma sample. The accuracy and precision of the assay were in accordance with FDA regulations for the validation of bioanalytical methods. The validated method was successfully applied to a pharmacokinetic study in six rats after oral administration of amitriptyline (15 mg/kg). This method allows laboratory scientists to rapidly determine amitriptyline and nortriptyline concentrations in plasma.

• Archives of Pharmacal Research
• /
• 제24권4호
• /
• pp.355-359
• /
• 2001

A novel HPLC method with electrochemical detection has been developed for the determination of recombinant human epidermal growth factor (rhEGF) in pharmaceutical products. rhEGF was separated from other components in formulation on a reversed-phase C18 column with 24% acetonitrile in 0.1 M phosphate buffer (pH 4.75). The optimum electrochemical oxidation of EGF was obtained at 0.85 V vs. Ag/AgCl in a glassy carbon working electrode due to electroactive tyrosine, tryptophan, methionine, and arginine residues. The quantitation range was from 1.0 to 200 ng of rhEGF with the linear correlation coefficient greater than 0.999. The method was successfully applied for the quantitation of rhEGF in a pharmaceutical preparation.

• Journal of Pharmaceutical Investigation
• /
• 제30권4호
• /
• pp.279-282
• /
• 2000

Simple and precise high-performance liquid chromatographic (HPLC) assay was developed and validated for the determination of a HMG-CoA reductase inhibitor, $lovastatin^{TM}$ and its active metabolite (mevinolinic acid) in human plasma. The method involved solid phase extraction of mevinolinic acid and internal standard using Sep-Pak Cartridge. Samples were analyzed by reversed-phase HPLC using $Capcell-Pak\;C_{18}$ column with ultraviolet detection at 238 nm. The quantitation limit of mevinolinic acid was 2 ng/ml and the calibration curve was linear over the range of 2-50 ng/ml $(r^2>0.999)$ with human plasma. The analyses of quality control samples indicated that the normal values could be predicted with an accuracy >97%. The intra- and inter-day coefficients of variation for the analyses were <10%. The average recoveries were similar (79%) for mevinolinic acid and methylmevinolinic acid. The method described has been successfully applied to the quantification of mevinolinic acid in about 1,000 human plasma samples over six-month period.

• 약학회지
• /
• 제48권5호
• /
• pp.278-284
• /
• 2004

In order to determine the bioavailability of c1onazepam, an anxiolytic drug, a simple, rapid and sensitive HPLC analysis was developed in healthy Korean volunteers. The analysis system was validated in specificity, accuracy, precision and linearity. The analysis condition we established was 2.58 min and 5 ng/$m\ell$ in retention time and limit of quantitation of c1onazepam, respectively, using reverse-phase C18 column connected to UV detector. Quantitation was performed at 235 nm wave length with p-hydroxybenzoic acid ethyl ester as internal standard. The method involved a simple extraction. In order to study blood level profiles as a function of time, eight volunteers were enrolled and orally took 6 mg clonazepam once. The blood samples were collected from 0 to 120 h after the drug administration. Mean AUC and Cmax value were 1028.17$\pm$568.165 (ng/$m\ell$$.$hr) and 41.25$\pm$10.82 (ng/$m\ell$), respectively. And mean Tmax and T$_{1}$2/ value were 1.08$\pm$0.42 (hr) and 30.78$\pm$3.26 (hr). From the results we determine the pharmacokinetic characteristics of clonazepam in Korean people using a newly developed and useful HPLC method.

• 한국축산식품학회지
• /
• 제41권2호
• /
• pp.335-342
• /
• 2021

Vitamin B12 deficiency may lead to serious health issues in both infants and adults. A simple analytical method involving sample pretreatment with enzyme, followed by cyanide addition under acidic conditions; separation on an immunoaffinity column; and high-performance liquid chromatography (HPLC) was developed for the rapid detection and quantitation of vitamin B12 in powdered milk. Detection limit and powdered milk recovery were determined by quantitative analysis. The limits of detection and quantitation were 2.71 and 8.21 ㎍/L, respectively. Relative standard deviations of the intra-day and inter-day precisions varied in the ranges of 0.98%-5.31% and 2.16%-3.90%, respectively. Recovery of the analysis varied in the range of 83.41%-106.57%, suggesting that the values were acceptable. Additionally, vitamin B12 content and recovery in SRM 1849a were 54.10 ㎍/kg and 112.24%, respectively. Our results suggested that the analytical method, including the sample pretreatment step, was valid. This analytical method can be implemented in many laboratory-scale experiments that seek to save time and labor. Therefore, this study shows that immunoaffinity-HPLC/ultraviolet is an acceptable technique for constructing a reliable database on vitamin B12 in powdered milk containing starch as well as protein and/or fat in high amounts.

• Natural Product Sciences
• /
• 제27권4호
• /
• pp.264-273
• /
• 2021

Simultaneous quantification of multiple marker compounds in herbal medicine by high performance liquid chromatography (HPLC) analysis is still a challenge due to the complexity in various parameters to be considered and co-existing multi-components. As a case study, a reliable HPLC method for simultaneous quantification of paeoniflorin from Paeoniae Radix and decursin from Angelicae Gigantis Radix in various commercial herbal medicine was developed based on analytical quality by design (AQbD) strategy. As a first step, risk assessment was performed to select the critical method parameters (CMPs) which were decided as organic mobile phase ratio and column oven temperature. In order to evaluate the effect of the CMPs on critical method attributes (CMAs) of peak resolution and tailing, central composite design (CCD) was employed. The final chromatographic conditions were optimized as follows: column- C₁₈, 4.6 × 250 mm, 5 ㎛ particle size; mobile phase- A: acetonitrile, B: 0.1% acetic acid water; detection wavelength- 235 nm for paeoniflorin, 325 nm for decursin; column oven temperature- 25℃; flow rate- 1.0 mL/min; gradient mobile phase system as Time (min) : % A, 0:14, 25:14, 30:50, 60:50, 61:100, 65:100, 66:14, 75:14. The method was successfully validated according to the International Conference on Harmonization (ICH) guidelines and piloted for ten commercial herbal medicines.