• Title/Summary/Keyword: Quantitation

Search Result 628, Processing Time 0.024 seconds

A quantitative determination of surfactant mixtures by FT-IR (FT-IR을 이용한 계면활성제 혼합물의 정량)

  • 최종근;노경원
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.21 no.2
    • /
    • pp.129-139
    • /
    • 1995
  • To confirm the usefulness of partial least-squares(PLS) and multiple scattering correction(MSC) method for quantitation of surfactants in [quantitative methods using FT-lR, reconsitituted mixtures of LAS, MES and ELA-9 were tested. Each mixture was dissolved in 50% EtOH, dried, and applied to the KBr cell. From the IR spectra of these mixture, the variance spectrum was obtained. After repeated calibrations for the various regios of this spectrum, we found that 1245-1130cm-1 and 1070-1010cm-1 showed the strong correlation with each component of the sample mixture: all the correlation coefficients were 1.000 and quantitative errors did not exceed 0.32%. From this result, we concluded that PLS method and MSC method are very useful and can be successfully applied to Quality control.

  • PDF

The effect of Taeumjowetang and Herba Ephedrae on the Obese mRNA and TNF-α mRNA in obesity-induced rats (태음조위탕(太陰調胃湯)과 마황(麻黃)이 비만(肥滿) 백서(白鼠)의 Leptin에 미치는 영향(影響))

  • Shin, Dong-jun;Kim, Dal-rae;Kim, Sun-hyung
    • Journal of Sasang Constitutional Medicine
    • /
    • v.13 no.1
    • /
    • pp.79-87
    • /
    • 2001
  • In order to investigate the effect of Taeumjowetang and Herba Ephedrae on obesity-induced rats, after Taeumjowetang and Herba Ephedrae were administered by mouth, and then body-weight, serum triglyceride, total cholesterol, Obese mRNA and TNF-${\alpha}$/ mRNA were measured. The reselts were as follows ; 1. The body-weight was decresed with the statistical significance in both the Taeumjowetang and the Herba Ephedrae group as compared with the control group. 2. The quantitation of serum triglyceride was decresed with the statistical significance in both the Taeumjowetang and the Herba Ephedrae group as compared with the control group. 3. The total cholesterol was slightly decresed in both the Taeumjowetang and the Herba Ephedrae group as compared with the control group, but there was no statistical significance. 4. The manifestation of Obese mRNA and TNF-${\alpha}$/ mRNA in epidymal, retroperitoneal, mesenteric and skeletal muscle tissues were inhibited in Taeumjowetang and Herba Ephedrae group. According to the above results, Taeumjowerang and Herba Ephedrae were recognized to be helpful for the treatment of obesity.

  • PDF

Blood Glucose Lowering Activity and Mechanism of Sangbackpitang (SBPT) in db/db Mouse (db/db 마우스에서 상백피탕의 혈당강하 활성 및 기전연구)

  • 이성현;안세영;두호경;정성현
    • YAKHAK HOEJI
    • /
    • v.43 no.6
    • /
    • pp.818-826
    • /
    • 1999
  • Antidiabetic activity and mechanism of Sangbackpitang (SBPT) was examined in db/db mice, which is a spontaneously hyperglycemic, hyperinsulinemic and obese animal model. SBPT and acarbose were administered orally for 4 weeks. Fasting and non-fasting serum glucose, glycated hemoglobin and triglyceride were all reduced when compared between db/db control group and SBPT treated group. At 12th week after birth, SBPT increased an insulin secretion although statistic significance was not seen. Total activities of sucrase, maltase and lactase in SBPT treated group were all decreased when compared to db/db control. On the other hand, sucrase and maltase activities in acarbose treated groups were increased. Effect of SBPT on mRNA expression of glucose transporter(GLUT-4) was also examined. Quantitation of glucose transporter was performed by RT-PCR and in vitro transcription with co-amplification of rat-action gene as an internal standard. Muscular GLUT-4 mRNA expression in SBPT treated group was increased significantly. These results may suggest that SBPT lowered blood glucose ascribing to inhibition of glycosidase-catalyzed reaction and upregulation of muscular GLUT-4 mRNA expression.

  • PDF

Analysis of Diethylcarbamazine and Diethylcarbamazine-N-oxide by Gas Chromatography

  • Lee, Suk-Hyang;M.S;Pharm.D
    • Archives of Pharmacal Research
    • /
    • v.19 no.6
    • /
    • pp.475-479
    • /
    • 1996
  • Diethylcarbamazine (DEC, 1-diethylcarbamyl-4-methylpiperazine) is an antiparasitic piperazine derivative used in the treatment of lymphatic filariasis caused by Wuchereria bancrofti, Brugia malayi or grugia timori. DEC-N-oxide is a major metabolite in humans and has antifilarial activity. In carrying out pharmacokinetic studies, gas chromatographic analysis of DEC in plasma can be complicated by the presence of the metabolite, since the thermally unstable DEC-N-oxide is converted back to a material which coelutes with DEC under the conditions of the analysis. We now report a method to separate DEC-N-oxide from DEC in plasma using solid phase extraction with subsequent gas chromatographic analysis using a nitrogen specific detector. One-diethylcarbamyl-4-ethylpiperazine (E-DEC) was the internal standard. The standard curve of DEC was linear in the range of 10 to 200 ng/ml as described by Y=0.0350+0.0128X, $R^2=0.999$. The limit of quantitation was 4 ng/mL. Reproducibility at 10, 100 and 200 ng/mL concentration points of the standard curve gave coefficient variations of 6.1%, 7.8% and 1.6%, respectively. The recovery following solid phase extraction was 99.3% for DEC and 94.8% for the internal standard. This sensitive and specific analytical method is suitable for pharmacokinetic studies of DEC.

  • PDF

Liquid Chromatographic Determination of Etofenprox Residues in Foods with Mass-Spectrometric Confirmation

  • Lee, Young-Deuk;Kwon, Chan-Hyeok;Kwon, Ki-Sung
    • Korean Journal of Environmental Agriculture
    • /
    • v.30 no.4
    • /
    • pp.432-439
    • /
    • 2011
  • BACKGROUND: An official analytical method was developed to determine etofenprox residues in agricultural commodities using high-performance liquid chromatography (HPLC). METHODS AND RESULTS: The etofenprox residue was extracted with acetone from representative samples of five raw products which comprised rice grain, apple, mandarin, cabbage, and soybean. The extract was then serially purified by liquid-liquid partition and Florisil column chromatography. For rice and soybean samples, acetonitrile/n-hexane partition was additionally coupled to remove nonpolar lipids. Reversed phase HPLC using an octadecylsilyl column was successfully applied to separate etofenprox from co-extractives. Intact etofenprox was sensitively detected by ultraviolet absorption at 225 nm. Recovery experiment at the quantitation limit validated that the proposed method could apparently determine the etofenprox residue at 0.02 mg/kg. Mean recoveries from five crop samples fortified at three levels in triplicate were in the range of 93.6~106.4%. Relative standard deviations of the analytical method were all less than 10%, irrespective of crop types. A selected-ion monitoring LC/mass spectrometry with positive atmospheric-pressure chemical ionization was also provided to confirm the suspected residue. CONCLUSION(s): The proposed method is simple, rapid and sensitive enough to be employed in routine inspection or monitoring of agricultural products for the etofenprox residue.

Simultaneous Determination of 4-Nitrotoluene and Benzophenone in Ground Water and Soil by Gas Chromatography-Mass Spectroscopy

  • Kwon, Oh-Seung;Kim, Eun-Young;Ryu, Jae-Chun
    • Analytical Science and Technology
    • /
    • v.16 no.1
    • /
    • pp.59-69
    • /
    • 2003
  • Benzophenone (BZP) and 4-nitrotoluene (4-NT) listed as endocrine disrupting chemicals are suspected to contaminate ground water sites and soil. Analytical method for simultaneous determination of the two chemicals in soil and ground water was developed by gas chromatography-mass spectrometry. Water (100 ml) was extracted with hexane, and soil (10 g) was extracted with methanol and hexane. Recovery in water was >72% for BZP and 90-118% for 4-NT. Recovery for 4-NT and BZP in soil was 51-59% with coefficient variation of less than 19.5%. Calibration curves showed a good linearity with $r^2=0.997$. In water and soil collected at nation-wide sites, BZP was found at 5 sites among 43 water sites at the concentration of $14.87{\pm}3.83ng/100 ml$. No 4-NT was found. It is suggested that this method is appropriate to the simultaneous quantitation of 4-NT and BZP in ground water and soil samples.

Purification and biochemical characterization of two novel antigens from Leishmania major promastigotes

  • Zeinali, Majid;Ardestani, Sussan K.;Kariminia, Amina
    • Parasites, Hosts and Diseases
    • /
    • v.45 no.4
    • /
    • pp.287-293
    • /
    • 2007
  • The identification and characterization of antigens that elicit human T cell responses is an important step toward understanding of Leishmania major infection and ultimately in the development of a vaccine. Micropreparative SDS-PAGE followed by electro transfer to a PVDF membrane and elution of proteins from the PVDF, was used to separate 2 novel proteins from L. major promastigotes, which can induce antibodies of the IgG2a isotype in mice and also are recognized by antisera of recovered human cutaneous leishmaniasis subjects. Fractionation of the crude extract of L. major revealed that all detectable proteins of interest were present within the soluble Leishmania antigens (SLA). Quantitation of these proteins showed that their expression in promastigotes is relatively very low. Considering the molecular weight, immunoreactivity, chromatographic and electrophoretic behavior in reducing and non-reducing conditions, these proteins are probably 2 isoforms of a single protein. A digest of these proteins was resolved on Tricine-SDS-PAGE and immunoreactive fragments were identified by human sera. Two immunoreactive fragments (36.4 and 34.8 kDa) were only generated by endoproteinase Glu-C treatment. These immunoreactive fragments or their parent molecules may be ideal candidates for incorporation in a cocktail vaccine against cutaneous leishmaniasis.

A Method to Monitor Dutasteride in Rat Plasma Using Liquid-Liquid Extraction and Multiple Reaction Monitoring: Comparisons and Validation

  • Kang, Myung Joo;Cho, Ha Ra;Lee, Dong Hoon;Yeom, Dong Woo;Choi, Young Wook;Choi, Yong Seok
    • Mass Spectrometry Letters
    • /
    • v.5 no.3
    • /
    • pp.79-83
    • /
    • 2014
  • Three different dutasteride extraction methods were compared and a method based on liquid-liquid extraction (LLE) using methyl tert-butyl ether and methylene chloride was proved to be more effective than others for the extraction of dutasteride and finasteride, the internal standard (IS), from rat plasma. Additionally, a method composed of the LLE extraction, liquid chromatography, and multiple reaction monitoring (MRM) to target dutasteride and IS was validated by assessing specificity, linearity ($r^2$ = 0.9993, 5 - 400 ng/mL), sensitivity (the limit of detection: 4.03 ng/mL; the limit of quantitation: 12.10 ng/mL), accuracy (intra-day: 89.4 - 105.9%; inter-day: 84.9 - 100.9%), precision (intra-day: 0.8 - 6.9%; inter-day: 2.9 - 15.9%), and recovery (84.7 - 107.8%). Since the validated method was successfully applied to a pharmacokinetic study of dutasteride, it can be useful for the pharmacokinetic evaluation of newly developed dutasteride formulations.

An Evaluation of Changes in the Allergenicity of Kochujang upon Preparation Using Aloe Extract

  • Son, Bo-Kyung;Huh, Yoon-Ee;Kim, Jung-Yun;Noh, Geon-Woong;Lee, Sang-Sun
    • Nutritional Sciences
    • /
    • v.9 no.4
    • /
    • pp.317-322
    • /
    • 2006
  • Soybeans are well-known as allergenic foods. Koreans consume large amounts of soybean foods, such as kochujang, which have gone through the fermentation process. To lower the allergenicity of these foods, we prepared hypo allergenic kochujang with aloe extract (AK). A sensory evaluation was conducted along with a clinical evaluation that used a double-blind, placebo-controlled food challenge (DBPCFC) test These tests were designed to evaluate the acceptability of the fermented foods. In comparison to normal kochujang (NK), AK elicited a higher sensory test score, and the rate of positive reactions in atopic dermatitis patients during the DBPCFC test was reduced. Methods of protein extraction, protein quantitation with sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), and protein identification using two-dimensional (2D) gel electrophoresis were performed for both NK and AK to compare the functional factors. We found a reduction in the levels of high molecular proteins even though the bands of the proteins had not entirely disappeared, indicating that the boiling and fermentation process changed the soybean protein patterns. The rate of the reduction of high molecular proteins was more effective in the AK. In conclusion, AK can be recognized as a food with hypoallergenic effect.

Determination of ${\alpha}-Keto$ Acids in Serum and Urine Using 1,2-Diamino-4,5-methylendioxybenzene as a Fluorescent Derivatizating Agent by High Performance Liquid Chromatography (HPLC법에 의한 1,2-디아미노-4,5-메틸렌디옥시벤젠을 형광유도체화제로 한 혈청 및 뇨 중의 ${\alpha}$-케토산의 분석)

  • Ok, Chi-Wan;Kim, Dae-Ki;Park, Song-Ja;Park, Jong-Sei
    • YAKHAK HOEJI
    • /
    • v.36 no.4
    • /
    • pp.370-378
    • /
    • 1992
  • A simple and sensitive high performance liquid chromatographic method to quantitate ${\alpha}-keto$ acids in serum and urine was investigated. ${\alpha}-Keto$ acids react with 1,2-diamino-4,5-methylenedioxybenzene (DMB) in the presence of 2-mercapto-ethanol and sodium hydrogen sulfite to form highly fluorescent derivatives, substituted 6,7-methylenedioxyquinoxalinol. The derivatization procedure was performed in water bath at $100^{\circ}C$, and completed within 50 min. By the use of a reversed-phase column and multi-step gradient with two solvents, a mixture containing twelve of these derivatives were efficiently resolved within 35 minutes. The optimal wavelengh of the fluorescence detector are ${\lambda}_{ex}=364\;nm$ and ${\lambda}_{em}=445\;nm$. The quantitation of the individual ${\alpha}-Keto$ acids was reproducible with relative standard deviation of $3.0{\sim}7.9%$ and had a detection limits of $10{\sim}60$ fmol, except for p-hydroxyphenylpyruvic acid (960 fmol).

  • PDF