• Analytical Science and Technology
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• v.34 no.1
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• pp.9-16
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• 2021

In the group of commonly prescribed β-blocker drugs, one of the enantiomers is generally relatively more active than the others. This study aims to develop a technique for the chiral analysis of select β-blockers based on proton nuclear magnetic resonance (1H-NMR) spectrometry. (S)-2-Tert-butyl-2-methyl-1,3-benzodioxole-4-carboxylic acid ((S)-TBMB) was synthesized and utilized as a chiral derivatizing agent. Pure β-blocker enantiomers were isolated from racemates by semi-preparative liquid chromatography prior to derivatization. The reaction time and concentration of (S)-TBMB were controlled to improve the derivatization procedure. No racemization was found during the analysis. High-performance liquid chromatography (HPLC) analysis was also performed for comparative purposes. High agreement between the NMR and HPLC methods was achieved in the determination of (R)-metoprolol in a standard solution of the (S) isomer.

• Korean Journal of Pharmacognosy
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• v.54 no.1
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• pp.38-43
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• 2023

A simple and accurate assay was developed for the quantitative analysis of 1-deoxynojirimycin (1-DNJ) derived from the silkworm (Bombyx mori). Normal-phase high-performance liquid chromatography coupled with an evaporative light scattering detector (HPLC-ELSD) and a hydrophilic interaction liquid chromatography column was used. Various parameters were applied to optimize the analysis method. The limits of detection and quantification of 1-DNJ were 2.97 × 10^-3 and 9.00 × 10^-3 mg/mL, respectively. The calibration curve showed good linearity results. The concentration range and the r² value were 0.0625-1.0 mg/mL and 0.9997, respectively. The accuracy test demonstrated a significantly high recovery rate (89.95-103.22%). The relative standard deviation was ≤ 1.00%. Thus, a method for the accurate identification and quantitative analysis of 1-DNJ in silkworms was developed. Moreover, in this procedure, the process of derivatization of 1-DNJ, which was required in previous experiments, could be eliminated. This technique may be actively utilized for the development of pharmaceuticals and health functional foods using 1-DNJ.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.306-312
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• 2015

The measurement of histamine is to determine the degree of allergy because the allergic reaction can lead to the release of histamine. In general, the antigen-antibody reaction was quantified by measuring absorbance using a microplate reader. In this study, we compare the method using a general antigen-antibody reaction and the method using a high performance liquid chromatography mass spectrometer (HPLC-MS) of chemical analysis in the measurement of histamine secretion. The cell line used was RBL-2H3, an allergic reaction was induced by stimulation with C48/80 (compound 48/80). Allergy-induced cells degranulation rate was confirmed by measurement of ${\beta}$-hexosaminidase and cytotoxicity was performed for the validity of the experiment. The quantitative determination of histamine showed a significant difference, since the quantitative limit of the measurement by the antigen-antibody reaction was 10.257 ppm while the quantitative limit of the measurement by HPLC-MS was 0.020 ppm. Measurement of histamine in allergic activity and anti-allergy tests showed that the HPLC-MS analysis rather than the analysis of the antigen-antibody reaction is a more precise and accurate test.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.2
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• pp.71-77
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• 2015

High-Performance Liquid Chromatography (HPLC) is a widely used method for measuring the concentration of chlorophyll a as an indicator for estimating phytoplankton biomass and primary production and also for identifying carotenoids to determine phytoplankton composition. However, tissue grinding procedure requires a lot of time and experience in the analysis of multiple sample. Accordingly, we measured the concentrations of photosynthetic pigments before and after the grinding, in order to understand the grinding effects on the quantitative analysis of chlorophylls and carotenoids using samples from southwestern East Sea. When tissue grinding procedure was omitted, we found that Chl a concentrations were underestimated up to 45% in average. Also, concentrations of Zeaxanthin, 19'-butanoyloxyfucoxanthin, 19'-hexanoyloxyfucoxanthin, biomarkers of pico and nano-size phytoplankton, were underestimated up to maximum 77~85% without grinding. We found that the smaller the phytoplankton, the bigger underestimation of their biomarker pigments concentration is likely to happen due to the incomplete extraction. Thus, tissue grinding procedure should be included for HPLC analysis in all cases, to prevent the underestimation of not only Chl a but also carotenoids pigments.

• Journal of the Korean Applied Science and Technology
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• v.10 no.1
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• pp.1-8
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• 1993

The possibilities for HPLC analysis of lipids have been revolutionised by the availability of evaporative light-scattering detectors, with which the response is independent of the nature of the mobile phase and does not depend On the presence of specific chromophores in the lipids. It was thus possible to develop an HPLC procedure, involving ternary gradient elution, for separating all the lipid classes in animal tissues in a single step. Although reversed-phase HPLC has been widely used for the analysis of molecular species of lipids, sliver ion chromatography can be a valuable alternative. For example, a stable silver ion column for HPLC was developed which permitted resolution of molecular species of triacylglycerols, even from such complex samples as fish oils, again With light-scattering detection and gradient elution. The capacity for HPLC resolution of diastereomeric diacyl-sn-glycerol derivatives, prepared from triacylglycerols. has lead to a new simple method for stereospecific analysis of the latter.

• Archives of Pharmacal Research
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• v.9 no.1
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• pp.5-9
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• 1986

Partialy purified ginseng proteins were either treated with sodium dodecyl sulfate (SDS) and .betha.-mercaptoethanol to denature the proteins or not, and subjected to Thin Layer Chromatography (TLC) and High Performance Liquid Chromatography (HPLC) to compare the components of each fraction. Standard proteins of known molecular weights (MW) were also either treated with SDS and .betha.-mercaptoethanol or not, and subjected to HPLC to obtain regression lines for MW determination. From the retention times obtained from samples in eiether case by HPLC, the MW were estimated as following in SDS treated condition, Gl fraction showed three peaks each with MW of above 100, 000, 51, 000 and 19, 000. Gll showed one original peak with MW of 21, 000 and Gll, two peaks each with MW of 19, 000 and 14, 000. On the other hand, in non-SDS treated condition, GI fraction showed two peaks each with MW of above 200, 000 NA 52, 000. Gll showed one original peak with MW of 41, 000 and Gill, three peaks each with MW of 28, 000, 19, 000 and 14, 000.

• Journal of Life Science
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• v.10 no.2
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• pp.115-124
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• 2000

The present study was undertaken to separate the available components effectively, such as tetrodotoxin(TTX), docosahexaenoic acid(DHA, C22:6,ω-3) and eicosapentaenoic acid (EPA, C20:5,ω -3) from pufferfish liver waste, which are known to have high values as bioactive materials. By using ultrafiltration, it was possible to separate high contents of 68mg TTX from pufferfish liver waste. In contrast, by activated charcoal column, it was to obtain about 54mg TTX. The recovering ratios were 65.3% and 45.0% in the two different methods of ultrafiltration and activated charcoal column, respectively. From the results of HPLC and gas chromatography-mass spectrometry(GC-MS), the obtained toxins were identified to be TTX and its derivatives. In addition, it was also possible to obtain 72.3g DHA and 11.4g EPA from 1kg of pufferfish liver by high performance liquid chromatography (HPLC). These amounts of DHA and EPA were also 17.70% and 1.04% in the total lipid of pufferfish liver oil from analysis of gas chromatography(GC), respectively.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.488-493
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• 2007

A survey for total aflatoxins (aflatoxins $B_1$, $B_2$, $G_1$, and $G_2$) was conducted on 245 cereals and processed cereal products, and 148 nuts and processed nut products in Korea, for a total of 393 commercialized ed samples. The total aflatoxins were quantified by the immunoaffinity column clean-up method with high performance liquid chromatography (HPLC) - fluorescence detection (FLD), and were confirmed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Total aflatoxins(AFs) were detected in 37 samples (9.4% incidence), including 2 millet samples, 1 mixed cereal (sunsik), 1 powdered malt sample, 2 processed cereal products, 6 peanut samples, 22 peanut butter samples, and 1 sample each of almonds, adlay tea, and a processed nut product. The contamination levels were $0.04-2.65{\mu}g/kg$ for aflatoxin $B_1$, and $0.04-5.51{\mu}g/kg$ for total aflatoxins. Finally, LC-MS/MS analysis of the contaminated samples was conducted to confirm the detected aflatoxins, and all 37 samples showing aflatoxins by HPLC-FLD were confirmed by LC-MS/MS.

• Analytical Science and Technology
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• v.26 no.6
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• pp.357-363
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• 2013

Selenium-containing proteins were separated from selenium-enriched yeast (SEY) using Trizol$^{(R)}$ reagent followed by anion exchange (AE) chromatography. This method is simpler and less time consuming than electrophoresis. Five selenium containing proteins were identified by on-line AE HPLC-ICP/MS (high performance liquid chromatography-inductively coupled plasma/mass spectrometry). Each protein was enzymatically hydrolyzed to seleno-amino acids and separated with RP (reverse phase) HPLC for the identification of selenoproteins.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.561-564
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• 2009

A high performance liquid chromatography (HPLC) method has been developed for determination of 11 ginsenosides in black ginseng (BG, white ginseng that is subjected to 9 cycles of $95^{\circ}C$ for 3 hr). After eluted by gradient elution of water-acetonitrile without buffer in 70 min, 11 ginsenosides in BG were identified. The proposed method provided good linearity ($R^2$>0.9995), accuracy (92.2-106.6%), and intra- and interday precision (RSD<2.6%). In addition, ginsenosides compositions in white, red, and black ginsengs were investigated using this method, respectively. Interestingly, in BG, the content of ginsenoside $Rg_3$ which does not existed in white ginseng was 7.51 mg/g, approximately 20 times than that in red ginseng.