• Title/Summary/Keyword: LC/MS/Ms

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The analysis of the urushiol congeners from the extracts of lacquer trees (옻나무 추출물 중 우루시올 동종체의 함량비 분석)

  • Cho, Yumi;Jung, Yu-Kyung;Kim, Jinsan;Lee, Joonbae;Paeng, Ki-Jung
    • Analytical Science and Technology
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    • v.22 no.1
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    • pp.65-74
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    • 2009
  • Active components of lacquer tree referred to as urushiol congeners, which are catechol derivatives with various alkyl or alkenyl substituents. The olefin side chains typically have one, two or three double bonds. In this study, the each congener's ratio analysis of extracts from korean lacquer tree are compared to the one from other asian lacquer tree. Extraction was performed using liquid-liquid extraction (LLE) method with soxhlet system from tree's bark and sap. Extracts were analyzed by reverse phase liquid chromatography and on-line electro spray ionization mass spectrometry (LC-MS/MS).

Simultaneous Determination of Ultra-Trace Pesticides and Synthetic Materials in Surface Water by LC-ESI-MS/MS (하천수에서 LC-ESI-MS/MS에 의한 극미량 농약류 및 합성원료의 동시분석법)

  • Hong, Seon-Haw;Lee, Jun-Bae;Lee, Soo-Hyung;Cho, Young-Hwan;Shin, Ho-Sang
    • Journal of the Korean Chemical Society
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    • v.59 no.3
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    • pp.225-232
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    • 2015
  • A liquid chromatography-electrospray ionization-tandem mass spectrometry method (LC-ESI-MS/MS) was used for determining seven pesticides (2,4-dichlorophenoxyacetic acid, methomyl, aldicarb, 2-methyl- 4-chlorophenoxy- acetic acid, molinate, carbaryl and carbofuran) and two synthetic materials (quinoline and bisphenol-A) in surface water. The analytes were extracted using solid-phase extraction (SPE). The eluate was concentrated by nitrogen gas. 100 microliters of 30% (v/v) methanol aqueous solution were used to dissolve the residue and an aliquot of the reconstituted solution was directly injected into LC-ESI-MS/MS after the filtration using 0.2 μm polytetrafluoroethylene (PTFE) syringe filter. Under the established condition, the calibration curves of the analytes were linear with correlation coefficients of above 0.997. The quantification limit was 0.002~0.011 μg/L and the relative standard deviations were less than 16.4%. In addition, accuracy was in the range of 84~107% and the recoveries were values between 56.2 and 98.6%. In this study, the developed method was applied to the analysis of real surface water samples.

Analytical Method for Determination of Cephalexin in Bovine Edible Tissues using Liquid Chromatography Coupled to Tandem Mass Spectrometry (LC-MS/MS를 이용한 소의 식용조직 중 세팔렉신의 잔류검사법)

  • Chae, Won-Seok;Lee, Sung Joong;Son, Song-Ee;Kim, Suk;Lee, Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.33 no.1
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    • pp.58-64
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    • 2018
  • An analytical method for the determination of cephalexin (CEX) in bovine tissues (muscle, liver, kidney and fat tissues) was developed and validated using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Tissue samples were extracted by the liquid-liquid extraction based on 5% trichloroacetic acid (TCA). The chromatographic separation was achieved on a reverse phase $C_{18}$ column with gradient elution using a mobile phase of 20 mM hexafluroacetylacetone (HFAC)/50% acetonitrile (40:60). The procedure was validated according to the Ministry of Food and Drug Safety guideline determining accuracy, precision, and limit of detection. Mean recoveries of CEX from spiked edible tissues ($6{\sim}1,500{\mu}g/kg$) were 83.9~106.8%, and the relative standard deviation was between 2.3 and 14.8%. Linearities were obtained with the correlation coefficient ($r^2$) of > 0.999. Limit of detection and limit of quantification for the investigated CEX were 2~10 and $6{\sim}30{\mu}g/kg$, respectively. This method was reliable, sensitive, economical and suitable for routine monitoring of CEX residues in bovine edible tissues.

Analysis of Sildenafil and its Analogues by LC/MS/MS (LC/MS/MS를 이용한 sildenafil 및 그 유사체 분석)

  • Myung, Seung-Woon;Park, So-Hee;Cho, Hyun-Woo
    • Analytical Science and Technology
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    • v.16 no.6
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    • pp.488-498
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    • 2003
  • By LC/MS/MS, the analytical method of sildenafil and its analogues (homosildenafil, vardenafil and tadalafil) used as used medical treatment of impotence was established. electrosprary ionization (ESI) and atmospheric pressure chemical ionization (APCI) as a ionization method were applied. Several parameter were varied and the sensitivity and reproducibility were compared. In LC/ESI-MS method, capillary voltage, cone voltage, extractor, entrance and RF lens to create appropriate productr ions for multiple reaction monitoring (MRM) were variable parameter, but the formation of the other product ions except the precursor ion could not detect. And the value of entrance, collision energy, exit, corona voltage, cone voltage, extractor, RF lens, cone gas, and desolvation gas in APCI mode were varied, only the creation pattern of fragment ions by the change of RF lens value were detected, and the limit of detection was decreased due to the increase of S/N. Ten millimole ammonium formate (pH 4.8):acetonitrile=70:30 by isocratic elution in HPLC system was shown the maximum sensitivity in MS, the detection limit of sildenafil, homosildenafil, vardenafil and tadalafil obtained by ESI-MRM were 0.10, 0.025, 0.025, and $0.25{\mu}g/mL$ at S/N>5, respectively.

Development of an Analytical Method for the Determination of Dexamethasone in Bovine Milk Using Liquid Chromatography Coupled to Tandem Mass Spectrometry (LC-MS/MS를 이용한 우유 중 덱사메타손의 잔류 분석법 개발)

  • Cha, Chun-Nam;Park, Eun-Kee;Yoo, Chang-Yeul;Lee, Sung Joong;Son, Song-Ee;Kim, Suk;Lee, Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.32 no.5
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    • pp.418-423
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    • 2017
  • An analytical method for the determination of dexamethasone (DM) in bovine milk samples was developed and validated using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Milk samples were extracted by the liquid-liquid extraction based on acetonitrile. The chromatographic separation was achieved on a reverse phase $C_{18}$ column with gradient elution using a mobile phase of 0.1% formic acid in 95% acetonitrile. The procedure was validated according to the Ministry of Food and Drug Safety guideline determining accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ). Mean recoveries of DM from spiked milk samples (25, 125, and 1,250 ng/mL) were 98.9-109.6%, and the relative standard deviation was between 1.7 and 4.4%. Linearity in concentration range of 12.5-1,250 ng/mL was obtained with the correlation coefficient ($r^2$) of 0.9997. LOD and LOQ for the investigated DM were 0.15 and 0.5 ng/mL depending on milk samples, respectively. This method was reliable, sensitive, economical and suitable for routine monitoring of DM residues in bovine milk.

Development of LC-MS/MS analytical methods for metalaxyl in Atractylodes macrocephala Koidzumi and Achyranthes japonica Nakai (LC-MS/MS를 이용한 생약 백출 및 우슬 중 Metalaxyl 잔류분석법 개발)

  • Yun, Myung-Sub;Yang, Seung-Hyun;Choi, Hoon
    • Journal of Applied Biological Chemistry
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    • v.65 no.1
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    • pp.17-21
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    • 2022
  • A new rapid and simple method for metalaxyl in Atractylodes macrocephala Koidzumi and Achyranthes japonica Nakai has been developed and validated. This study was conducted to develop a method for analyzing metalaxyl by a method based on QuEChERS using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Samples were extracted with acetonitrile and purified using amino-propyl (NH2) Solid Phase Extraction cartridge. The method limit of quantitation (MLOQ) was 0.01 mg/kg. The linearity of matrix-matched calibration curve (r2) was ≥0.99 at the calibration range of 0.001-0.05 mg/kg. For recovery test, Atractylodes macrocephala Koidzumi or Achyranthes japonica Nakai was treated with standard solutions at MLOQ and 10MLOQ levels. Recovery rates were in the range of 88.1-109.1% with <5.5% coefficient of variation. This established analytical method was fully validated. Based on these results, it can contribute to improving the safety of residual pesticides in Atractylodes macrocephala Koidzumi and Achyranthes japonica Nakai.

Comparative study on the efficiency of pesticide residue removal in foods (Perilla Leaves, Strawberries, Apples)

  • Seung-Woon Myung
    • Analytical Science and Technology
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    • v.37 no.1
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    • pp.1-11
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    • 2024
  • In agricultural households cultivating vegetables and fruits, the use of various pesticides to protect crops from diseases and pests or to control weeds is widely practiced enhancing quality and productivity. However, pesticides can pose a threat to consumer health by remaining on the food surface or migrating into the food interior. Households commonly peel off skins, wash with water, or use chemical methods to remove foreign substances including residual pesticides on the food surface. In this study, we measured the washing rate by comparing the pesticide concentrations before and after washing in the leafy vegetable perilla leaves and the fruits strawberries and apples, which were intentionally exposed to pesticides. We compared washing rates using tap water, a baking soda solution, and a commercially available food-specific cleaning solution. The target pesticides for analysis were azoxystrobin, bifenthrin, boscalid, difenoconazole, flubendiamide, and indoxacarb, and the residual pesticide analysis was performed using GC-MS/MS or LC-MS/MS. The removal rates of pesticides were highest with the food-specific cleaner, followed by baking soda and tap water in order.

Determination and Monitoring of Grayanotoxins in Honey Using LC-MS/MS (LC-MS/MS를 이용한 벌꿀 중 grayanotoxin 분석법 연구 및 실태조사)

  • Lee, Sook-Yeon;Choi, Youn-Ju;Lee, Kang-Bong;Cho, Tae-Yong;Kim, Jin-Sook;Son, Young-Wook;Park, Jae-Seok;Im, Sung-Im;Choi, Hee-Jung;Lee, Dong-Ha
    • Korean Journal of Food Science and Technology
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    • v.40 no.1
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    • pp.8-14
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    • 2008
  • This study was performed to establish analysis methods, and evaluated for grayanotoxin in domestic/foreign honey and wild honey. The molecular weight of grayanotoxins I, II and III, excluding grayanotoxin III that has been commercialized, were analyzed by LC-MS/MS. Then, the molecular structure of grayanotoxins I and II were analyzed by NMR. A total 111 samples (25 Korean honey, 21 Korean wild honey, 13 Korean honeycomb honey, 44 foreign honey, 8 foreign wild honey) were examined to determined whether or not each sample contained grayanotoxins I, II, and III. The honey samples were mixed with methanol and loaded into a tC18 cartridge, the filtrate was diluted with water, and the mixture was then analyzed by ESI triple-quadrupole LC-MS/MS. Grayanotoxins were only found in the foreign wild honey and were not detected in Korean honey, Korean honeycomb honey, or Korean wild honey. Three of the samples contained grayanotoxin I, II, and III, and one sample contained only grayanotoxins I and III. The lowest level for grayanotoxin I was 3.13 ${\pm}$ 0.00 mg/kg, and the highest level was 12.93 ${\pm}$ 0.01 mg/kg. The levels of grayanotoxin II were 0.84 ${\pm}$ 0.01 mg/kg, 0.92 ${\pm}$ 0.00 mg/kg and 1.08 ${\pm}$ 0.01 mg/kg, respectively. The lowest level of grayanotoxin III was 0.25 ${\pm}$ 0.01 mg/kg and the highest level was 3.29 ${\pm}$ 0.74 mg/kg. Through this study, safety management for foreign wild honey has been enabled.

Quantitative Analysis of Flavonoids from Salicomia herbacea L. Extracst by LC-MS (LC/MS에 의한 퉁퉁마디의 Flavonoids 정량 분석)

  • Kim, Ha-Song;Yoon, Young-Seung;Cho, Jai-Woo
    • Korean Journal of Medicinal Crop Science
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    • v.16 no.4
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    • pp.231-237
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    • 2008
  • This study was conducted to determine the amount of flavonoids in Salicomia herbacea L. grown by a liquid chromatography / mass spectrometry (LC/MS). The flavonoids-contained quercetin (124.43 ppm), rutin (2.57 ppm), quercetin-3-${\beta}$-glucoside (3992.49 ppm), quercetin-3',4'-glucoside (0.08 ppm) and isorhamnetin (27.81 ppm) were detected in the powder sample. In particular, quercetin-3-${\beta}$-glucoside accounted for more than 99% in hay and 96% in powder. These results suggest that S. herbacea, which is one of halophyte plants, has high functional substances as an antioxidant source.

Analysis of Gingerol Compounds of Raw Ginger (Zingiber officinale Roscoe) and Its Paste by High Performance Liquid Chromatograph-Mass Spectrometry (LC/MS) (LC/MS에 의한 원료생강 및 생강 페이스트 중의 Gingerol 화합물 분석)

  • 조길석
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.5
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    • pp.747-751
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    • 2000
  • This study was carried out to improve the analysis method of gingerol compounds from ginger (Zingiber officinale Roscoe). Pungent components of ginger were extracted by acetone and lisolated by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) with LiChrosorb RP-18 column. Three homologues of gingerols were identified by HPLC-mass spectrometry (LC/MS) and nuclear magnetic resonance (NMR). The contents of [6]-, [8]- and [10]-gingerols in three homologues identified were 635.3 mg%, 206.6 mg% and 145.7 mg% in raw ginger, and were 418.2 mg%, 142.6 mg% and 103.3 mg% in ginger paste, respectively.

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