• Title/Summary/Keyword: high performance liquid chromatography

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Pharmacokinetics of ofloxacin in Patients with Multidrug-Resistant Tuberculosis (다제내성결핵 환자에서 ofloxacin의 약동학적 분석)

  • Park, Seung-Kyu;Yoon, Young-Ran;Lee, Woo-Chul;Jun, Hyung-Min;Shon, Ji-Hong;Kim, Kyoung-Ah;Park, Ji-Young;Shin, Jae-Gook
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.2
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    • pp.128-136
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    • 2002
  • Background: There are few studies that have reported on the pharmacokinetic(PK) disposition of fluoroquinolones in patients with multi-drug resistant tuberculosis(MDR-Tb), even though fluoroquinolones are frequently co-prescribed to those patients. In this study, the PK disposition of ofloxacin, a fluoroquinolone, was evaluated in patients with MD R -Tb. Methods: Twenty patients with MDR-Tb were given 2nd line Tb drugs including ofloxacin (300mg twice a day), prothionamide, cycloserine, para-aminosalicylic acid, kanamycin, and streptomycin. The patients were grouped according to their body mass index(BMI) as an index of emaciation (group A : 18.5$\leq$BMI <23, group B : BMI < 18.5). Blood samples were serially drawn and urine samples were collected upto 24 hours after the last dose of those drugs at steady state (over 1 month). The ofloxacin concentrations were determined using HPLC (High Performance Liquid Chromatography). Results: The AUC of ofloxacin in group B was greater than that in group A ($31.4{\pm}8.9{\mu}g/ml{\cdot}h$ vs. $24.1{\pm}6.2{\mu}g/ml{\cdot}h$)(Check the symbols), (p<0.05). The total clearance(Cl/F) of ofloxacin was $0.16{\pm}0.03$ L/h/kg in group A, and $0.14{\pm}0.03$ L/h/kg in group B. The half-lives of ofloxacin in two groups were similar (group A : $5.3{\pm}0.8$ hours, group B : $5.7{\pm}0.9$ hours). In addition, the other PK parameters in two groups were also similar. Conclusions: The pharmacokinetics of ofloxacin in patients with MDR-Tb appears to be comparable with those of normal subjects, and the extent of emaciation appears to have an influence on the pharmacokinetics of ofloxaicn in chronic debilitated MDR-Tb patients.

Neuroprotective Effects of Modified Yuldahanso-tang (MYH) in a Parkinson's Disease Mouse Model (MPTP로 유도된 Parkinson's disease 동물 모델에서 열다한소탕 가감방 (MYH)의 신경 세포 보호 효과)

  • Go, Ga-Yeon;Kim, Yoon-Ha;Ahn, Taek-Won
    • Journal of Sasang Constitutional Medicine
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    • v.27 no.2
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    • pp.270-287
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    • 2015
  • Objectives To evaluate the neuroprotective effects of modified Yuldahanso-tang (MYH) in a Parkinson's disease mouse model. Methods 1) Four groups (each of 8 rats per group) were used in this study. 2) The neuroprotective effect of MYH was examined in a Parkinson's disease mouse model. C57BL/6 mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg/day), intraperitoneal (i.p.) for 5 days. 3) The brains of 2 mice per group were removed and frozen at $-20^{\circ}C$, and the striatum-substantia nigra part was seperated. The protein volume was measured by Bradford method following Bio-Rad protein analyzing kit. Using mouse/Rat Dopamine ELISA Assay Kit. 4) The brains of 2 mice per group were separated and removed. TH-immunohistochemical was examined in the MPTP-induced Parkinson's disease mice to evaluate the neuroprotective effects of MYH on ST and SNpc. 5) Two mice out of each group were anesthetized and skulls were opened from occipital to frontal direction to take out the brains. The brains added TTC solution for 20 minutes for staining. 6) The water tank used for morris water maze test was filled with $28^{\circ}C$ water, and a round platform of 10cm in diameter was installed for mice to step on. The study was carried out once a day within 30 seconds, keep exercising to step on the platform in the pool. 7) The brains of two mice out of each group were fixed in 10% formaldehyde solution and paraphillin substance was infiltrated. They were fragmented by microtome, and observed under an optical microscope after Hematoxylin & Eosin staining. 8) A round acrylic cylinder with its upper side open was filled with clean water and depressive mouse models were forced to swim for 15 minutes. After 24 hours the animals were put in the same equipment for 5 minutes and were forced to swim. 9) The convenient, simple, and accurate high-performance liquid chromatography (HPLC) method was established for simultaneous determination of Neurotransmitters in MPTP-MYH group. Results 1) MYH possess Dopamine cell protective effect on MPTP-induced injury in striatum and substantia nigra pars compacta. 2) MYH inhibits the loss of tyrosine hydroxylase-immunoreacitive (TH-IR) cells in the striatum and substantia nigra pars compacta on MPTP-induced injury in C57BL/6 mice. 3) MYH possesses improvement effect on MPTP-induced memory deterioration in C57BL/6 mice through the reduction of prolongated Sort of lost time by MPTP injection using the Morris water maze test. 4) MYH possesses hippocampal neuron protective effect on MPTP-induced injury in C57BL/6 mice. 5) MYH possesses improvement effect on MPTP-induced motor behaviour deficits and depression in C57BL/6 mice through the reduction of prolongated losing motion by MPTP injection using the Forced swimming test. 6) MYH increases serotonin product amount on MPTP-induced injury in C57BL/6 mice. Conclusions This experiment suggests that the neuroprotective effect of MYH is mediated by the increase in Dopamin, TH-ir cell, Hippocampus and Serotonin. Furthermore, MYH essential oil may serve as a potential preventive or therapeutic agent regarding Parkinson's disease.

Validation of a Method and Evaluation of Antioxidant Activity for the Simultaneous Determination of Riboflavin and Coixol in Coix lacryma-jobi var. ma-yuen Stapf Sprouts (율무 새싹 추출물의 Riboflavin과 Coixol의 동시 분석법 검증 및 항산화 활성)

  • Lee, Ji Yeon;Park, Jung Yong;Park, Chun-Geon;Kim, Dong Hwi;Ji, Yun-Jeong;Choi, Su Ji;Oh, MyeongWon;Hwang, Hosop;Lee, Yunji;Jeong, Jintae;Lee, Jeong Hoon;Seo, Kyung Hye
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.4
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    • pp.452-458
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    • 2019
  • Coix lacryma-jobi var. ma-yuen (Rom. Caill.) Stapf (CL), which contains riboflavin and coixol, has traditionally been used to treat cancer and arthritis. However, no method for the simultaneous determination of riboflavin and coixol in CL sprouts has been established. In this study, we established and validated a high-performance liquid chromatography-diode array detection (HPLC-DAD) method for the identification and quantification of two reference markers, riboflavin and coixol, in CL sprout extracts. CL sprouts (whole sprouts and leaves) were subjected to extraction with 70% ethanol at room temperature and at 80 ℃ under reflux conditions. The two extractions were validated with respect to specificity, accuracy, precision, and linearity. The content of the two reference markers was highest in leaves extracted under reflux conditions (riboflavin, 8.23 ± 0.32 mg/g; coixol, 5.95 ± 0.04 mg/g). We also investigated the antioxidant activity of the extracts via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+) scavenging assays. The results indicated that extracts obtained from sprouts under reflux conditions had the strongest antioxidative effects (DPPH half maximal inhibitory concentration [IC50], 68.9 ± 4.1 g/mL; and ABTS, IC50, 34.9 ± 0.1 g/mL). These results can serve as baseline data for the simultaneous determination of the two reference marker compounds, riboflavin and coixol, and development of functional food materials using CL sprouts.

Development of an Official Analytical Method for Determination of Imazapyr in Agricultural Commodities using HPLC-UVD (HPLC-UVD를 이용한 농산물 중 Imazapyr의 공정분석법 확립)

  • Jang, Jin;Kim, Heejung;Ko, Ah-Young;Lee, Eun-Hyang;Joo, Yoon Ji;Kim, Jinhong;Chang, Moon-Ik;Rhee, Gyu-Seek
    • The Korean Journal of Pesticide Science
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    • v.19 no.1
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    • pp.5-13
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    • 2015
  • A chromatographic method for the determination of imazapyr, a non-selective herbicide, in agricultural commodities was developed to use safety control of pesticide residue on crops, and was fully validated as an official method for residue analysis. Agricultural commodities, mandarin (fruit), hulled rice (cereal grains), pepper (vegetables), potato (potatoes) and soybean (beans) were extracted with methanol and partitioned with dichloromethane to remove the interference obtained from sample extracts, adjusting pH to 2.5 by 4N hydrochloric acid. Finally, they were analyzed by high performance liquid chromatography coupled to UV detector (HPLC-UVD). The developed method had the linearity in the range of test concentrations with coefficients of determination ($r^2$) more than 0.99. Recovery studies were carried out at three concentration levels (LOQ, 10LOQ, and 50LOQ) performing five replicates at each level. Recoveries were ranged between 72.1 to 108.0%, with relative standard deviations less than 10%. A consistent recovery was determined according to the CODEX guidelines (CAC/GL40, 2003). Finally, LC/MS with selected ion monitoring was also applied to confirm the suspected residues of imazapyr in agricultural samples. This developed method for determination of imazapyr residues in agricultural commodities. can be used as an official method.

Immunogenicity of Synthetic Peptide Specific for Major Immunogenic Determinat of Hepatitis B Surface Antigen (B형간염(型肝炎) 표면항원(表面抗原)의 주면역원(主免疫原) 결정기(決定基)에 특이(特異)한 합성(合成) Peptide의 면역원성(免疫原性)에 관한 연구(硏究))

  • Shin, Kwang-soon;Han, Su-nam
    • Korean Journal of Veterinary Research
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    • v.25 no.1
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    • pp.7-17
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    • 1985
  • Many investigators have been pursuing various attempts so far to produce hepatitis B surface antigen(HBsAg) vaccines using the techniques such as isolation from plasma of chronic HBsAg carrier, recombinant DNA technique or preparation of synthetic peptides specific for immunogenic determinants. Hepatitis B virus can not grow on any cell lines by the tissue culture technique at the present time. The plasma of chronic HBsAg carrier is expensive and its source is limited. The HBsAg from the recombinant DNA technique gave still very low yield. Another approach, therefore, has been initiated to develop a synthetic hepatitis B virus vaccine. The possible use of several distinct synthetic vaccines in prophylaxis can be facilitated by availability of full synthetic immunogens. Peptides synthesized for potential application as antiviral vaccines have been mostly tested in the form of conjugates with carrier proteins, although the free synthetic peptide can be immunogenic. To understand basic knowledges on the antigenicity and immunogenicity of a synthetic peptide specific for major immunogenic determinant of HBsAg, a nonapeptide, $H_2N^{139}Cys-Thr-Lys-Pro-Thr-Asp-Gly-^{146}Asn-Aba$ COOH, which corresponds to HBsAg amino acid residues 139 to 147, was synthesized by the Merrifield's solid-phase method with a slight modification. The antigenicity and immunogenicity of this specific synthetic peptide were examined comparing with purified plasma-derived natural HBsAg. The results obtained are as follows; 1. The peptide synthesized showed the identical amino acid composition to the theoretical value. The degree of purification and molecular weight were acertained by methods of high performance liquid chromatography and mass spectrometry. 2. Using m-maleimidobenzoyl-N-hydroxysuccinimide ester as a conjugating agent, the synthetic peptide was conjugated to rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin. Their conjugation yields were 8.3, 9.5, 15.8, 13.5, and 11.2%, respectively. 3. The natural HBsAg was purified from plasma of chronic HBsAg carrier. By the electron microscopic observation of the purified natural HBsAg preparation, no Dane particles were observed and the preparation showed negative DNA polymerase activity. 4. Antigenicity of the synthetic peptide and the plasma-derived natural HBsAg was determined by competition radioimmunoassay using $^{125}I$-natural HBsAg. Their 50% inhibitions appeared as $90{\mu}g/ml$ and $0.12{\mu}g/ml$ for the synthetic peptide and the natural HBsAg, respectively. This indicates that the former was about 750-fold less antigenic than the latter. 5. Immunogenicity of the synthetic peptide was determined by administering the peptide-carrier conjugates into rabbits with and without Freund's complete adjuvant. Regardless the carrier proteins and adjuvant, positive immune responses to the synthetic peptide were observed. The higher antibody titers, however, were shown in the groups administered with Freund's complete adjuvant. 6. Immunizing dose 50% in mice of the various peptide-carrier conjugates was 5.47, 6.00, 65.16, 31.25 and $13.03{\mu}g/dose$ for rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin, respectively, while the natural HBsAg showed $0.65{\mu}g/dose$. 7. It was postulated that homologous proteins prefer to heterologous ones as the carriers.

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A Comparative Study on Quantifying Uncertainty of Vitamin A Determination in Infant Formula by HPLC (HPLC에 의한 조제분유 중 비타민 A 함량 분석의 측정불확도 비교산정)

  • Lee, Hong-Min;Kwak, Byung-Man;Ahn, Jang-Hyuk;Jeon, Tae-Hong
    • Korean Journal of Food Science and Technology
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    • v.40 no.2
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    • pp.152-159
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    • 2008
  • The purpose of this study was to determine the accurate quantification of vitamin A in infant formula by comparing two different standard stock solutions as well as various sample weights using high performance liquid chromatography. The sources of uncertainty in measurement, such as sample weight, final smaple vloume, and the instrumental results, were identified and used as parameters to determine the combined standard uncertainty based on GUM(guide to the expression of uncertainty in measurement) and the Draft EURACHEM/CITAC Guide. The uncertainty components in measuring were identified as standard weight, purity, molecular weight, dilution of the standard solution, calibration curve, recovery, reproducibility, sample weight, and final sample volume. Each uncertainty component was evaluated for type A and type B and included to calculate the combined uncertainty. The analytical results and combined standard uncertainties of vitamin A according to the two different methods of stock solution preparation were 627 ${\pm}$ 33 ${\mu}$g R.E./100 g for 1,000 mg/L of stock solution, and 627 ${\pm}$ 49 ${\mu}$g R.E./100 g for 100 mg/L of stock solution. The analytical results and combined standard uncertainties of vitamin A according to the various sample weighs were 622 ${\pm}$ 48 ${\mu}$g R.E./100 g, 627 ${\pm}$ 33 ${\mu}$g R.E./100 g, and 491 ${\pm}$ 23 ${\mu}$g R.E./100 g for 1 g, 2 g, and 5 g of sampling, respectively. These data indicate that the preparation method of standard stock solution and the smaple amount were main sources of uncertainty in the analysis results for vitamin A. Preparing 1,000 mg/L of stock solution for standard material sampling rather than 100 mg, and sampling not more than 2 g of infant formula, would be effective for reducing differences in the results as well as uncertainty.

Analysis and Risk Assessment of Benzo(a)pyrene in Edible Oils (식용유지류 중 벤조피렌의 함량 분석 및 안전성 평가)

  • Jang, Mi-Ra;Hong, Mi-Sun;Jung, So-Young;Choi, Bu-Chuhl;Lee, Kyeong-Ah;Kum, Jin-Young;Kim, Il-Young;Kim, Jung-Hun;Chae, Young-Zoo
    • Journal of Food Hygiene and Safety
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    • v.29 no.2
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    • pp.141-145
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    • 2014
  • To assess the health risk for benzo(a)pyrene by the intake of edible oils, 288 cases of edible oils collected from food markets were analysed using the high performance liquid chromatography with fluorescence detector. The levels of benzo(a)pyrene were from non-detection to $4.78{\mu}g/kg$, and the average was $0.11{\mu}g/kg$. The chronic daily exposures of benzo(a)pyrene for total population group and consumer-only group were estimated using the food consumption data in the fifth Korea National Health and Nutrition Examination Survey in 2011. The estimated daily intake of benzo(a)pyrene was $4.26{\times}10^{-3}ng/kg$ b.w./day for total population group and $7.64{\times}10^{-3}ng/kg$ b.w./day for consumer-only group. The MOE (margin of exposure) of benzo(a)pyrene for total population group and consumer-only group was $7.28{\times}10^7{\sim}1.74{\times}10^8$ and $3.95{\times}10^7{\sim}9.42{\times}10^7$, respectively. Accordingly, the health risk from benzo(a)pyrene caused by the intake of edible oils was considered as a very low level.

A Study on the Analysis of Five Artificial Sweetners in Beverages by HPLC/MS/MS (HPLC/MS/MS를 이용한 음료류 중 인공감미료 동시분석에 관한 연구)

  • Lee, Seong-Bong;Yong, Kum-Chan;Hwang, Sun-Il;Kim, Young-Su;Jung, You-Jung;Seo, Mi-Young;Lee, Chang-Hee;Sung, Jin-Hee;Yoon, Mi-Hye
    • Journal of Food Hygiene and Safety
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    • v.29 no.4
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    • pp.327-333
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    • 2014
  • A method for analysis of five artificial sweetners (sodium saccharin, aspartame, acesulfame-K, sucralose, cyclamate) in beverage samples was developed using high-performance liquid chromatography/triple quadrupole mass spectrometry (HPLC/MS/MS). The method uses a single-step dilution for sample preperation. Seperation was achieved on a $C_{18}$ column ($2.1{\times}150mm$, $3.5{\mu}m$) with A- 2% methanol (1 mM ammonium acetate), B-95% methanol (1 mM ammonium acetate) as mobile phase with gradient mode. The quantitation of target compounds was performed by external calibration in selected reaction monitorning (SRM) mode. The coefficient of determination of calibration curve for sodium saccharin, aspartame, acesulfame-K, sucralose and cyclamate were 0.9957, 0.9991, 0.9943, 0.9982 and 0.9948, respectively. The limits of detection (LODs) and limits of quantitation (LOQs) were in the range of 0.001~0.022 mg/L and 0.004~0.073 mg/L, repectively. Recoveries for beverage samples were in the range of 92.76~113.50% with RSD < 10.91%. The method has applied to the determination of the five sweetners in 102 beverage samples. Three artificial sweetners-aspartame, acesulfame-K, sucralose were detected from 42 samples. Sodium saccharin and cyclamate were not detected in all samples.

Determination of Polycyclic Aromatic Hydrocarbons in Smoked Food Products (훈연식품 중 polycyclic aromatic hydrocarbons 함량 분석)

  • Seo, Ilwon;Nam, Hejung;Lee, Songyoung;Lee, Kyueun;Shin, Han-Seung
    • Food Engineering Progress
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    • v.13 no.3
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    • pp.195-202
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    • 2009
  • This study was accomplished that analysis of seven polycyclic aromatic hydrocarbons (PAHs) in smoked or nonsmoked processing foods by high performance liquid chromatography (HPLC) with fluorescence detection. The calibration line was constructed with injected different levels of standard concentration. Limit of detection (LOD) and limit of quantification(LOQ) showed higher linearity ($r^{2}$=0.998) reasonably, and recovery exhibited 0.033-0.666 $\mu$g/kg, 0.108-2.217 $\mu$g/kg and 69.31-90.14%, respectively. As a result, the samples using smoked tuna as smoked materials contained seven PAHs with different range from 0.256 to 0.486 $\mu$g/kg. The benzo[a]pyrene, indicator of PAHs, was detected to below the LOQ in two samples. Concentrations of benzo[a]pyrene in three samples were below the 2 $\mu$g/kg which is the limit of regulation. Smoked tuna sauces were detected from 0.321 to 0.552 $\mu$g/kg and not detected in drying powders. PAHs of smoked meat products were ranged from 0.720 to 2.027 $\mu$g/kg and are higher than concentration of tuna smoked samples. PAHs were very low in non-smoked foods including mustard, herb, and roasted meats.

Method Development for Determination of Chlorogenic Acid and Arbutin Contents in Fruits by UHPLC-MS/MS (UHPLC-MS/MS를 이용한 과일류 중 클로로젠산 및 알부틴 동시분석법 개발)

  • Choi, Young-Ju;Jeon, Jong-Sup;Kim, Woon-Ho;Jung, You-Jung;Ryu, Ji-Eun;Choi, Jong-Chul;Chae, Kyung-Suk;Lee, Jin-Hee;Do, Young-Sook;Park, Young-Bae;Yoon, Mi-Hye
    • Journal of Food Hygiene and Safety
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    • v.34 no.5
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    • pp.413-420
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    • 2019
  • In this study, a sample preparation method and a simultaneous determination method by ultra-high performance liquid chromatography coupled with tandem mass spectrometry for 9 isomers of chlorogenic acid and arbutin in fruits were developed. The samples were extracted using 90% methanol (pH 3.0), with the solutions being shaken and then sonicated for 10 min each. After centrifugation at 4,000 rpm for 10 min, the extraction was concentrated under a vacuum at $40^{\circ}C$ using a vacuum evaporator. The residue was dissolved in 5 mL of 5% methanol and filtered through a $0.45{\mu}m$ membrane before UHPLC-MS/MS analysis. The separations were performed on a C18 column with gradient elution of water (containing 0.1% formic acid) and methanol (containing 0.1% formic acid). The specificity, linearity, limit of detection, limit of quantification, accuracy, and precision of the proposed methods were also evaluated.