• 한국식품영양과학회지
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• 제3권1호
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• pp.53-68
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• 1974

The thiohydantoin derivative derived from amino acid was used for the stepwise sequence analysis of peptide or protein from the carboxyl termini. Recently, SUZUKI reported the mass spectrometric identification about a part of these compounds. In this paper, was described the mass spectrometric identification of thiohydantoins derived from 20 amino acids. Mass spectra were obtained with a mass spectrometer, JEOL model JMS-06H and samples were introduced with a direct inlet probe. The molecular ion peaks and fragment ion peaks were identified easily, because these peaks appeared differently every amino acids and specially, it was easy discrimination between leucine and isoleucine. It is suggested that mass spectrometry was one of the useful methods to identify thiohydantoins derived from amino acids.

• Nuclear Engineering and Technology
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• 제29권4호
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• pp.327-335
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• 1997

The correlation of isotope composition of uranium, plutonium and neodymium with the burnup in M uranium dioxide fuel has been investigated experimentally. The total and fractional($^{235}$ U) burnup were determined by Nd-148 and, U and Pu mass spectrometric method respectively. The isotope compositions of these elements, after their separation from the fuel samples were measured by mass spectrometric. The content of the elements in the irradiated fuel ore determined by isotope dilution mass spectrometric method using $^{233}$ U, $^{242}$ Pu and $^{150}$ Nd as spikes. The content of plutonium in the irradiated fuel was expressed by the correlation with uranium isotopes. The correlations between isotope compositions themselves and the total and fractional burnup ore compared with those calculated from ORIGEN2 code.

• 한국유전체학회:학술대회논문집
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• 한국유전체학회 2006년도 The 15th Korean Genome Organization Conference KOGO 2006 Annual Meeting
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• pp.41-41
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• 2006

• Nuclear Engineering and Technology
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• 제47권7호
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• pp.924-933
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• 2015

The correlation of the isotopic composition of uranium, plutonium, neodymium, and cesium with the burnup for high burnup pressurized water reactor fuels irradiated in nuclear power reactors has been experimentally investigated. The total burnup was determined by Nd-148 and the fractional $^{235}U$ burnup was determined by U and Pu mass spectrometric methods. The isotopic compositions of U, Pu, Nd, and Cs after their separation from the irradiated fuel samples were measured using thermal ionization mass spectrometry. The contents of these elements in the irradiated fuel were determined through an isotope dilution mass spectrometric method using $^{233}U$, $^{242}Pu$, $^{150}Nd$, and $^{133}Cs$ as spikes. The activity ratios of Cs isotopes in the fuel samples were determined using gamma-ray spectrometry. The content of each element and its isotopic compositions in the irradiated fuel were expressed by their correlation with the total and fractional burnup, burnup parameters, and the isotopic compositions of different elements. The results obtained from the experimental methods were compared with those calculated using the ORIGEN-S code.

• 한국시뮬레이션학회논문지
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• 제22권4호
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• pp.139-147
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• 2013

본 논문에서는 질량 분석 방법에 의하여 산출된 단백체 데이터(mass spectrometric proteomic data)의 분류 분석(classification analysis)을 위한 새로운 특성 선택(feature selection) 방법을 제안한다. 이 방법은 i)높은 상관관계를 가지는 중복된 특성을 효과적으로 제거하는 전처리 단계와 ii)토너먼트(tournament) 전략을 사용하여 최적 특성 부분집합(optimal feature subset)을 탐색해 내는 단계로 구성되어 있다. 제안되는 방법을 실제 암진단에 사용되는 공개된 혈액 단백체 데이터에 적용하였으며 널리 사용되는 타 방법과 비교할 때 우수한 성능과 균형된 특이도와 민감도를 달성함을 실증하였다.

• 분석과학
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• 제8권4호
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• pp.553-559
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• 1995

An extraction chromatographic method of separating rare earth impurities from high purity $Nd_2O_3$, $Sm_2O_3$, $Gd_2O_3$, $Er_2O_3$, $Dy_2O_3$ and $Yb_2O_3$ was studied by using $HCl-NH_4Cl$ as moving phase and P507 as stationary phase. After the impurities were enriched from the eluate by chelant-activated carbon, the active carbon was ashed and the ignited residue was used to prepare the sample electrode for spark source mass spectrometric determination. The impurities in 99.9999% rare earth oxide can be determined by the proposed method with recovery over 80%.

• 분석과학
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• 제35권2호
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• pp.82-91
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• 2022

Grayanotoxin-contaminated honey exhibits toxicity. In this study, a reliable and sensitive liquid-chromatography-tandem-mass-spectrometric method (LC-MS/MS) was developed and validated for the quantitation of grayanotoxin I and grayanotoxin III in honey. The grayanotoxins were extracted from honey via solid phase extraction and separated on a biphenyl column with a mobile phase consisting of 0.5 % acetic acid in water and methanol. Mass spectrometric detection was performed in the multiple-reaction monitoring mode with positive electrospray ionization. The calibration curve covered the range 0.25 to 100 ㎍/g. The intra- and inter-day deviations were less than 10.6 %, and the accuracy was between 94.3 and 114.0 %. The validated method was successfully applied to the determination of grayanotoxins in mad honey from Nepal. The concentrations of grayanotoxin I and grayanotoxin III in 33 out of 60 mad honey samples were 0.75 - 64.86 ㎍/g and 0.25 - 63.99 ㎍/g, respectively. The method established herein would help in preventing and confirming grayanotoxin poisoning.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.51.2-51.2
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• 2015

Understanding interfacial phenomena has been one of the main research issues not only in semiconductors but only in life sciences. I have been trying to meet the atomic scale surface and interface analysis challenges from semiconductor industries and furthermore to extend the application scope to biomedical areas. Optical imaing has been most widely and successfully used for biomedical imaging but complementary ion beam imaging techniques based on mass spectrometry and ion scattering can provide more detailed molecular specific and nanoscale information In this presentation, I will review the 27 years history of medium energy ion scattering (MEIS) development at KRISS and DGIST for nanoanalysis. A electrostatic MEIS system constructed at KRISS after the FOM, Netherland design had been successfully applied for the gate oxide analysis and quantitative surface analysis. Recenlty, we developed time-of-flight (TOF) MEIS system, for the first time in the world. With TOF-MEIS, we reported quantitative compositional profiling with single atomic layer resolution for 0.5~3 nm CdSe/ZnS conjugated QDs and ultra shallow junctions and FINFET's of As implanted Si. With this new TOF-MEIS nano analysis technique, details of nano-structured materials could be measured quantitatively. Progresses in TOF-MEIS analysis in various nano & bio technology will be discussed. For last 10 years, I have been trying to develop multimodal nanobio imaging techniques for cardiovascular and brain tissues. Firstly, in atherosclerotic plaque imaging, using, coherent anti-stokes raman scattering (CARS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) multimodal analysis showed that increased cholesterol palmitate may contribute to the formation of a necrotic core by increasing cell death. Secondly, surface plasmon resonance imaging ellipsometry (SPRIE) was developed for cell biointerface imaging of cell adhesion, migration, and infiltration dynamics for HUVEC, CASMC, and T cells. Thirdly, we developed an ambient mass spectrometric imaging system for live cells and tissues. Preliminary results on mouse brain hippocampus and hypotahlamus will be presented. In conclusions, multimodal optical and mass spectrometric imaging privides overall structural and morphological information with complementary molecular specific information, which can be a useful methodology for biomedical studies. Future challenges in optical and mass spectrometric imaging for new biomedical applications will be discussed.

• Mass Spectrometry Letters
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• 제15권1호
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• pp.1-25
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• 2024

Protein glycosylation, a highly significant and ubiquitous post-translational modification (PTM) in eukaryotic cells, has attracted considerable research interest due to its pivotal role in a wide array of essential biological processes. Conducting a comprehensive analysis of glycoproteins is imperative for understanding glycoprotein bio-functions and identifying glycosylated biomarkers. However, the complexity and heterogeneity of glycan structures, coupled with the low abundance and poor ionization efficiencies of glycopeptides have all contributed to making the analysis and subsequent identification of glycans and glycopeptides much more challenging than any other biopolymers. Nevertheless, the significant advancements in enrichment techniques, chromatographic separation, and mass spectrometric methodologies represent promising avenues for mitigating these challenges. Numerous substrates and multifunctional materials are being designed for glycopeptide enrichment, proving valuable in glycomics and glycoproteomics. Mass spectrometry (MS) is pivotal for probing protein glycosylation, offering sensitivity and structural insight into glycopeptides and glycans. Additionally, enhanced MS-based glycopeptide characterization employs various separation techniques like liquid chromatography, capillary electrophoresis, and ion mobility. In this review, we highlight recent advances in enrichment methods and MS-based separation techniques for analyzing different types of protein glycosylation. This review also discusses various approaches employed for glycan release that facilitate the investigation of the glycosylation sites of the identified glycoproteins. Furthermore, numerous bioinformatics tools aiding in accurately characterizing glycan and glycopeptides are covered.

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1864-1866
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• 2009