• Journal of the Korean Chemical Society
• /
• v.59 no.3
• /
• pp.225-232
• /
• 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.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.1
• /
• pp.33-36
• /
• 2001

The experiments were conducted to establish the in vitro culture system of apple rootstock M.9. The meristem tissue of M.9 were pre-treated in antiox: dant solution containing 100 mgL$^{-1}$ ascorbic acid and 150 mgL$^{-1}$ citric acid for 30 minutes, transferred to the MS liquid medium added with 0.1 mgL$^{-1}$ IBA, 0.5 mgL$^{-1}$ GA, and 30 gL$^{-1}$ sucrose, which shaked by 50 rpm for 2 weeks, and then, cultured in same composition of MS agar medium. This treatment stimulated shooting from the tissue, the most favorably, compared with other treatments. All young shoots produced normal roots when they were shake-cultured on the 1/2MS liquid medium added with 0.5 mgL$^{-1}$ IBA, 30 gL$^{-1}$ sucrose and 1,000 times diluted solution of Hormex by 50 rpm for one week, and subsequently transferred to the 8 gL$^{-1}$ agar medium of the same composition as pre-culture medium minus Hormex.

• Korean Journal of Plant Resources
• /
• v.31 no.6
• /
• pp.675-683
• /
• 2018

This study describes an efficient and widely applicable droplet-vitrification following cryopreservation for shoot tips of Chrysanthemum morifolium (Ramat.) cvs. 'Borami' and 'Yes morning'. The shoot tips of Chrysanthemum were precultured in Murashige and Skoog (MS) liquid medium supplemented with sucrose (0.3-0.7 M). Precultured explants were treated with loading solution (LS, C6) containing glycerol 20% and sucrose 20% for 30 min and exposed to dehydration solution (B5) containing 40% of glycerol and 40% of sucrose for 60 min at $25^{\circ}C$, and then transferred onto droplets containing $2.5{\mu}l$ PVS3 on sterilized aluminum foils ($4cm{\times}0.5cm$) prior to direct immersion in liquid nitrogen (LN) for 1 h. The highest regeneration rate (%) was obtained when shoot tips were precultured with treatment-2 (exposing of shoot tips to MS + 0.3M sucrose for 30 h and then treated with MS+0.5 M sucrose for 16 h) at $25^{\circ}C$ in both the cultivars. The viability of cooled samples, followed by culturing on $NH_4NO_3$-free MS medium for first 5 days was increased to two-fold (80.7%) regrowth rate over those cultured on normal MS medium or MS medium containing plant growth regulators. This result shows droplet-vitrification would be a promising method for cryobanking chrysanthemum germplasm.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.21 no.3
• /
• pp.111-123
• /
• 2008

Objectives : We aimed to investigate therapeutic effect of Bojungikgitang-gamibang(BI) and Mahwangshingungsan(MS) by observing changes in blood cells and the nasal mucosa of Sprague-Dawley(SD) rats with allergic rhinitis. Methods : Twenty-four SD rats were divided into three groups: normal, control, and sample group. Allergic rhinitis was induced in the control and sample group by intraperitoneal and intranasal sensitization with 0.1% and 0.4% Ovalbumin solution. Then BI was orally administered only to the sample group along with MS for 28days, while the rats in the control group was given normal saline. Results : BI and MS showed significantly decreased IgE level on the serum of the rat model, Bl and MS showed significantly decreased eosinophil level on the blood of the rat model. BI and MS inhibited the inflammatory reaction on the nasal mucosal tissue, according to nasal mucosal biopsy. Bl and MS had anti-allergic according to level, eosinophil level, nasal mucosal biopsy. BI and MS had no hepatoxicity, according to AST and ALT on the serum. Conclusion : According to the above results, it is considered that Bl and MS is helpful in treatment of allergic rhinitis.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.5
• /
• pp.745-750
• /
• 2007

An isotope dilution-liquid chromatography/tandem mass spectrometric method was developed as a candidate reference method for the accurate determination of folic acid in infant milk formula. Sample was spiked with 13C5-folic acid and then extracted with phosphate buffer (pH 6) solution. The extract was further cleaned up by deproteinization followed by a C18 solid-phase extraction cartridge. The extract was analyzed by using LC/ ESI/MS/MS with selectively monitoring the collisionally induced dissociation channels of m/z 442 → m/z 295 and m/z 447 → m/z 295, which are the neutral glutamyl loss from the [M+H]+ ions of folic acid and 13C5-folic acid, respectively. LC/MS/MS chromatograms showed substantially reduced background from chemical noises compared to LC/MS chromatograms. Repeatability and reproducibility studies showed that the LC/MS/ MS method is a reliable and reproducible method which can provide less than 1.5 relative percentage of method precision.

• Bulletin of the Korean Chemical Society
• /
• v.26 no.12
• /
• pp.1991-1995
• /
• 2005

Sensitivity factors of elements by a glow discharge mass spectrometry (GD-MS) were intensively investigated and compared with a laser ablation inductively coupled plasma-mass spectrometry (ICP-MS). In case of copper matrix, the sensitivity factor by GD-MS generally decreases with the increase of the mass number of element. The details are a little different between each data measured by Faraday and multiplier detectors. The factor by a multiplier detector drastically decreases with the mass increase in the region of low mass as in Faraday detector’s case, but slowly in the high mass region. On the contrast, the sensitivity factor of solution standard by a conventional ICP-MS slowly increases with the increase of elemental mass number even though there are some exceptions such as gold and also the sensitivity factor by a laser ablation ICP MS generally increases with mass number of element in the specimen of glass type. In case of steel matrix, any definite trends could not be shown in the relationship between the GD-MS’s sensitivity factor and elemental mass.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.4 no.5
• /
• pp.919-930
• /
• 2000

This paper treats a development of visual interactive modeling(VIM) system for ship scheduling problem in integer formulation. The ship scheduling problem can be described as "A problem which assigns ships and cargos to achieve maximum revenue from transportation" in brief. Since late 1970s there has been rapid growth in development and use of VIM as MS10R technology due to the development of computer technology and now VIM has become a important discipline in MS/OR and MIS society. Visual Interactive Modeling is a process that decision maker takes part in modeling life cycle -data collection, formulation, derivation of optimal solution and representation of solution - and interacts with a modeling system to achieve a user-solution appropriate for his/her ultimate goal. This paper suggests the methodology how to collect data, build and modify model, and represent solution using computer graphics as a major driving tool and demonstrates effective performance of a prototype system.pe system.

• Korean Journal of Environmental Agriculture
• /
• v.28 no.2
• /
• pp.202-208
• /
• 2009

The dechlorination of endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepine-3-oxide) and its metabolite, endosulfan sulfate via reaction with zerovalent iron under various pH conditions was studied using aqueous solution. The reaction products, which were probably produced from endosulfan and endosulfan sulfate by ZVI were identified by GC-MS. The lower the pH of reaction solution, the higher the transformation rate of endosulfan and endosulfan sulfate. The transformation rates of endosulfan and endosulfan sulfate in pH 3.0 by ZVI were 28% and 90% but those of endosulfan and endosulfan sulfate in mixture solution of water/acetone were 65% and 92%, respectively. The pH of reaction solution after ZVI treatment was increased to pH 10. Endosulfan was hydrolyzed at pH 10 but endosulfan sulfate was not hydrolyzed. Two unknown peaks were produced from endosulfan sulfate by treatment of ZVI. As a result of GC-MS analysis, unknown peaks were guessed to be structural isomer substituted hydrogen for chlorine.

• Journal of Pharmaceutical Investigation
• /
• v.37 no.2
• /
• pp.79-84
• /
• 2007

This study was aimed to establish analytical method of Bi to develop a guideline of the bioequivalence test of tripotassium dicitrato bismuthate (TDB). For this purpose, a simple, specific and sensitive inductively coupled plasma-mass spectrometry (ICP/MS) method were developed and validated in human plasma. Various concentrations of bismuth standard solution (0-25ng/mL) were prepared with distilled water and human blank plasma. To 10mL of the volumetric flasks, 2mL of blank plasma was added with 8ml of distilled water. Bi standard solution was added to prepare the calibration samples and injected into ICP-MS. The plasma samples obtained from volunteers given 3 tablets of bismuth (total 900mg as TDB) were analyzed as described above. As a result, the coefficients of variation were <20% in quantitation limit (0.2 ng/mL) and <15% at the rest of concentrations. The stability test by repeated freezing-thawing cycles showed that the samples were stable only for 24hr. The stability tested for samples with a short-term period of storage at room temperature and pre-treatment prior to the analysis showed very stable over 24hr. In 8 healthy Korean subjects received Denol tablets at the dose of 900mg bismuth, AUC, $C_{max},\;T_{max}$ and half-life $(t_{1/2})$ were determined to be $198.33{\pm}173.78 ng{\cdot}hr/mL,\;64.48{\pm}27.06 ng/mL,\;0.52{\pm}0.21 hr,\;and\;5.15{\pm}2.67 hr$, respectively, from the plasma bismuth concentration-time curves. In conclusion, the method was suitable for the determination of bismuth in human plasma samples and could be applied to bioequivalence test of bismuth tablet.

• Korean Journal of Plant Resources
• /
• v.19 no.3
• /
• pp.385-391
• /
• 2006

In vitro-grown axillary buds of Melia aredarach were successfully cryopreserved by vitrification. On the MS medium supplemented with BA 1 mg/L, multiple shoots were developed within $4{\sim}5$ weeks. Plantlets of Melia azedarach were cold-hardened at $10^{\circ}C$ for a 16-hr photo-period for 6 weeks. Excised axillary shoot-tips from hardened plantlets were precultured on a solidified Murashige & Skoog agar medium (MS) supplemented with 0.7 M sucrose for 1 day at $25^{\circ}C$. Axillary shoot-tip meristems wert dehydrated using a highly concentrated vitrification solution (PVS2) for 60 min at $0^{\circ}C$ prior to a direct plunge into liquid nitrogen (LN). The PVS2 vitrification solution consisted of 30% glycerol (w/v), 15% ethylene glycol (w/v), 15% DMSO (w/v) in MS medium containing 0.4M sucrose. After short-term warming in a water bath at $40^{\circ}C$, the meristems were transferred into 2 ml of MS medium containing 1.2M sucrose for 15 min and then planted on solidified MS culture medium. Successfully vitrified and warmed meristems resumed growth within 2 weeks and directly developed shoots without intermediary callus formation. The survival rate of cold-hardened plantlets for 3 and 4 weeks was 90%. We did not find any difference in PCR-band patterns between control and cryopreserved plants. This method appears to be a promising technique for cryopreserving axillary shoot-tips from in vitro-grown plantlets of Medicinal plants.