• Korean Journal of Veterinary Service
• /
• v.26 no.3
• /
• pp.199-202
• /
• 2003

Solid phase extraction(SPE) and matrix solid phase dispersion(MSPD) have been studied as preparation procedures for tetracyclines analysis by high-performance liquid chromatography(HPLC) in meat. The recovery range was 74${\sim}$98% for SPE, and 72${\sim}$93% for MSPD at spiked levels of 100ng/g for oxytetracycline(OTC), tetracycline(TC), chlortetracycline(CTC), and doxycycline(DC). The detection limits were 15${\sim}$78ng/g for SPE and 25${\sim}$84ng/g for MSPD, respectively. Analytical method was HPLC with UV detector. The purpose of this study was developing a practical, accurate and precise method for rapid extraction and quantitation of tetracycline residues in meat.

• Bulletin of the Korean Chemical Society
• /
• v.29 no.2
• /
• pp.352-356
• /
• 2008

An analytical method has been developed for measuring chlorostyrenes in fish tissue sample. Extraction of chlorostyrenes from fish tissue was carried out by ultrasonication using acetone/n-hexane (5:2, v/v) mixture. Most of the lipids in the extract were eliminated by freezing-lipid filtration, prior to solid-phase extraction (SPE) cleanup. During freezing-lipid filtration, about 90% of the lipids extracted from the fish samples were easily removed without any significant losses of chlorostyrenes. For purification, SPE using Florisil was used for the rapid and effective cleanup. Quantification was performed using gas chromatography-mass spectrometry in the selected ion monitoring mode. Spiking experiments were carried out to determine the recovery, precision, and limits of detection (LODs) of the method. The overall recovery was above 80% in the spiked fish tissue sample at 10 and 100 ng/g levels, respectively. The detection limits for chlorostyrenes were ranged from 0.05 to 0.1 ng/g. This developed method is demonstrated to give efficient recoveries and LODs for detecting chlorostyrenes spiked into fish tissue with high lipid content.

• Korean Journal of Pharmacognosy
• /
• v.43 no.3
• /
• pp.250-256
• /
• 2012

In order to extract the curcuminoid such as curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC) in turmeric (Curcuma longa), solvent extraction methods (dipping and ultrasonic extraction method) and solid-phase extraction (SPE) were used. RP-HPLC (reverse-phase high-performance liquid chromatography) and TLC (thin-layer chromatography) were used for identification and analysis the three curcuminoid. From the experimental results, it is evident that the percentage of curcuminoid extracted from turmeric by ultrasonic extraction method was higher than dipping method. The percentage of curcumin extracted from turmeric by pure methanol was higher than any aqueous methanolic composition. Moreover, the total peak area of three curcuminoid was above 92% in RP-HPLC using solid-phase extraction. These results will form a database for investigating the constituents of natural products and the resources of pharmaceutical, nutrition, and cosmetic products.

• Journal of Dairy Science and Biotechnology
• /
• v.33 no.1
• /
• pp.27-34
• /
• 2015

The aim of this study was to optimize a simple, fast, and economic analytical method for the simultaneous determination of various pesticides (aldrin, p,p'-DDT, o,p'-DDT, p,p'-DDE, ${\alpha}$-endosulfan, ${\beta}$-endosulfan, dieldrin, heptachlor, permethrin, chlordane, deltamethrin, diazinon, bifenthrin, methoprene, propargite, fenpropathrin, cypermethrin, fenvalerate, and fenpropathrin) in milk by using dispersive solid phase extraction (SPE). In this study, two different extraction methods (low temperature cleanup and liquid-liquid partitioning), which were followed by a cleanup process based on dispersive-SPE, were evaluated and compared for the 19 pesticides. The results for all the pesticides were determined by gas chromatography mass spectrometry (GC/MS) with selected-ion monitoring mode, and the matrix effect of the method was evaluated. Comparison of these approaches yielded higher and more consistent recoveries of most pesticides at fortification levels of $1{\mu}g/mL$ using low-temperature fat precipitation, followed by cleanup process based on dispersive-SPE with PSA and C18 as sorbents, than other preparation process. The relative standard deviation was <20 % and the combination of this method were very effective for the cleanup.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.10
• /
• pp.4927-4935
• /
• 2012

Turmeric is a medicinal herb with various pharmacological activities. Curcumin, demethoxycurcumin(DMC) and bisdemethoxycurcumin(BDMC) were extracted from turmeric by dipping and ultrasonic wave method. And extraction efficiency was identified using solid phase extraction(SPE). The extracted sample were simultaneously separated and analyzed from three kinds of commercial $C_{18}$ reversed-phase high performance liquid chromatography using water and acetonitrile as mobile phase with isocratic elution mode. Flow rate 1.0mL/min, injection volume $10{\mu}L$ and column oven temperature $40^{\circ}C$ at 425nm wavelength has been conducted. From the experimental results, the optimum mobile phase composition of water/acetonitrile 50/50vol% using RS tech column. It is evident that the amount of curcuminoids extracted(extraction time 4h) by 100% MeOH was higher than any aqueous MeOH composition. Finally, in 100% water extraction, the amount(mAU${\times}$mim) of curcuminoids extracted by SPE was 14.3 and 24.5 times respectively higher than ultrasonic wave and dipping method. The shown results can be applied as sources for pharmaceuticals and functional material.

• YAKHAK HOEJI
• /
• v.46 no.6
• /
• pp.392-397
• /
• 2002

A simple and sensitive high performance liquid chromatographic method to quantitate ursodeoxycholic acid in crude drug pharmaceuticals was investigated. Ursodeoxycholic acid react with 2-bromoacetyl-6-methoxynaphthalene (Br-AMN) in the presence of triethylamine to form highly fluorescent derivative. The derivatization procedure was performed at 7$0^{\circ}C$ and completed within 30 min. The optimal wavelength of the fluorescence detector are λ$_{ex}$=300 nm and λ$_{em}$ = 460 nm. The LOD of the ursodeoxycholic acid was 25 ng/mι based on the S/N =3, and the LOQ was 80 ng/mι based on S/N = 10. Crude drug pharmaceuticals pretreated by solid phase extraction (Sep-pak $C_{18}$ cartridge) which were shown very good separation and recovery values for the compound.d.

• Journal of Environmental Science International
• /
• v.12 no.1
• /
• pp.81-86
• /
• 2003

The study was carried out to evaluate the new analytical method of phthalate esters(diethylphthalate, di-n-butylphthalate, butylbenzylphthalate, bis(2-ethylhexyl)phthalate), one of the endocrine disruptors, which were performed by GC/MS-SIM(selected ion monitoring). The phthalate esters were extracted from water samples using solid-phase extraction on $C_{18}$ columns. It investigated that the extraction recovery rate of phthalate esters with different solvents and solvent volume. The optimal solvent was dichloromethane and proper volume of dichloromethane for recovery of phthalate esters was 4 mL. There were good linearities(above $R^2$=0.9975) in the range 0.01~0.50mg/L, and the detection limits were below 0.01~0.03$\mu\textrm{g}$/L. The recovery rates, RSD and MDLs for phthalate esters were 80~114%, 5.0~8.1% and 0.03~0.11$\mu\textrm{g}$/L, respectively. This method shows a good precision of phthalate esters.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2002.08a
• /
• pp.142.1-142
• /
• 2002

• Bulletin of the Korean Chemical Society
• /
• v.27 no.9
• /
• pp.1315-1322
• /
• 2006

The following study describes the gas chromatography-mass spectrometry (GC-MS) based screening and confirmation analysis of urinary androgenic steroids. Four commercially available solid-phase extraction (SPE) cartridges, Serdolit PAD-1, Sep-pak $C_{18}$, amino-propyl, and Oasis HLB, and three different extractive organic solvents, diethyl ether, methyl tert-butyl ether (MTBE), and n-pentane, were tested for sample preparation. Overall, Oasis HLB combined with MTBE extraction provided the highest recoveries in 39 of 46 total androgenic steroids examined and it showed a good extraction yield (>82.1%) for polar steroids, such as metabolites of fluoxymesterone, oxandrolone, and stanozolol, which gave a poor recovery in both n-pentane (9.2-64.3%) and diethyl ether (22.2-73.6%) extractions. All SPE sorbents tested showed potential, because they were efficient in extraction for most or selective steroids. When applied to positive urine samples based on the results obtained, the present method allowed selective and sensitive analysis for detection of urinary androgenic steroids. The experiments showed that the high-resolution MS method is clearly more efficient than the low-resolution MS technique for the detection of many urinary steroids. However, comprehensive sample clean-up procedures also might be needed especially in confirmation analysis to increase detectability.

• Journal of agriculture & life science
• /
• v.45 no.5
• /
• pp.73-80
• /
• 2011

Fifty substances of pesticide were selected for analysis through the historical investigation of pesticides detected from environmental-friendly agricultural soil, and the environmental-friendly agricultural soils in Gyeongnam area were collected and then were accepted Anve (accelerated solvent extraction) and SPve (solid-phase extraction) as multiresidue extraction and clean up methods suitable to the soils. The pesticide residues were analyzed by using GC/vCD/NPD, HPLC/UV/FL, GC/MSD, or HPLC/MSD. 50 kinds of pesticides for the soils were an average of 95.5% from retrieval ratio of the 72 to 118% range, and the average of 3.0% for CV (%). Among 40 samples of soil, 20 components were detected from pesticide residues of 21 samples, and average amounts detected for these components were 0.035 for endosulfan, 0.043 for ethoprophos, 0.020 for chlorpyrifos, 0.023 for chlorfenapyr, 0.047 for flufenoxuron, 0.070 for fenvalerate, 0.266 for cypermethrin, 0.016 for lufenuron, 0.022 for bifenthrin, 0.025 for fenobucarb/BPMC, 0.043 for difenoconazole, 0.059 for fenarimol, 0.020 for kresoxim-methyl, 0.026 for tetraconazole, 0.039 for isoprothiolane, 0.017 for iprobenfos, 0.014 for nolrimol, 0.156 for fluquinconazole, 0.047 for tebuconazole, and 0.045 mg/kg for oxadiazon. Therefore it is infered that the establishment of pesticide residues limit for environmental-friendly agricultural soil is needed as soon as possible.