A5081772701- Mass Spectrometry Techniques and Applications
- Analytical Chemistry and Chromatography
- Metabolomics and Mass Spectrometry Studies
- Advanced Proteomics Techniques and Applications
- Analytical chemistry methods development
- Forensic Fingerprint Detection Methods
- Advanced Chemical Sensor Technologies
- Microbial Natural Products and Biosynthesis
- Advanced Photocatalysis Techniques
- Glycosylation and Glycoproteins Research
- Biosensors and Analytical Detection
- Pharmacological Effects and Assays
- Shoulder Injury and Treatment
- Shoulder and Clavicle Injuries
- Rheumatoid Arthritis Research and Therapies
- Hormonal and reproductive studies
- Effects and risks of endocrine disrupting chemicals
- Molecular Biology Techniques and Applications
- Oral microbiology and periodontitis research
- Pharmaceutical and Antibiotic Environmental Impacts
- Toxic Organic Pollutants Impact
- Gene expression and cancer classification
- Heavy Metal Exposure and Toxicity
- TiO2 Photocatalysis and Solar Cells
- Forensic Toxicology and Drug Analysis
Dongguk University
2020-2024
Hankuk University of Foreign Studies
2011-2020
Northeastern University
2010-2015
Yong In University
2015
Iowa State University
2007-2010
Ames National Laboratory
2007-2010
United States Department of Energy
2010
Kosin University Gospel Hospital
2010
Catholic University of Korea
1999-2000
Graphite-assisted laser desorption/ionization (GALDI) mass spectrometry (MS) was investigated for analysis of cerebrosides in a complex total brain lipid extract. Conventional MALDI MS and GALDI were compared regarding by using high-vacuum (HV, <10-6 Torr) LDI time-of-flight intermediate-pressure (IP, 0.17 linear ion trap spectrometry. Cerebrosides not detected or with low sensitivity because other dominant phospholipids. By GALDI, as intense peaks without prior separation from species while...
Due to a high background in the low-mass region, conventional MALDI is not as useful for detecting small molecules (molecular masses <500 Da) it large ones. Also, spatial inhomogeneity that inherent crystalline matrixes can degrade resolution imaging mass spectrometry (IMS). In this study, colloidal graphite was investigated an alternative matrix laser desorption/ionization (GALDI) IMS. We demonstrate its advantages over detection of such organic acids, flavonoids, and oligosaccharides....
Summary Laser desorption/ionization (LDI)‐based imaging mass spectrometry (MS) has been applied to several biological systems obtain information about both the identities of major chemical species and their localization. Colloidal graphite‐assisted LDI (GALDI) MS was introduced for small molecules such as phospholipids, cerebrosides, oligosaccharides, flavonoids, other secondary metabolites with high spatial homogeneity due finely dispersed particles. Mass profiles images Arabidopsis...
Colloidal silver laser desorption/ionization (LDI) mass spectrometry (MS) was employed to directly profile and image epicuticular wax metabolites on a variety of different surfaces Arabidopsis thaliana leaves flowers. Major cuticular compounds, such as very long-chain fatty acids, alcohols, alkanes, ketones, were successfully detected adduct ions. The surface flower organs (carpels, petals, sepals) profiled for the first time at spatial resolution ∼100 μm. In addition, spectral profiles...
Abstract We introduce UnaG as a green-to-dark photoswitching fluorescent protein capable of high-quality super-resolution imaging with photon numbers equivalent to the brightest photoswitchable red protein. only fluoresces upon binding fluorogenic metabolite, bilirubin, enabling UV-free reversible easily controllable kinetics and low background under Epi illumination. The on- off-switching rates are controlled by concentration ligand excitation light intensity, respectively, where dissolved...
Gene and protein expression changes observed with tumorigenesis are often interpreted independently of each other out context biological networks. To address these limitations, this study examined several approaches to integrate transcriptomic proteomic data known protein-protein signaling interactions in estrogen receptor positive (ER+) breast cancer tumors. An approach that built networks from differentially expressed proteins identified among them enriched genes yielded the greatest...
The lack of experimental characterization the structures and ligand-binding motifs therapeutic G-protein coupled receptors (GPCRs) hampers rational drug discovery. human cannabinoid receptor 2 (hCB2R) is a class-A GPCR promising target for small-molecule cannabinergic agonists as medicines. Prior mutational modeling data constitute provisional evidence that AM-841, high-affinity classical cannabinoid, interacts with cysteine C6.47(257) in hCB2R transmembrane helix 6 (TMH6) to afford improved...
Triacylglycerols (TAGs), essential energy storage lipids, are easily detected by conventional MALDI MS when occurring on their own. However, signals overwhelmed other mainly phosphatidylcholines (PCs) and, therefore, require purification. In order to profile TAGs from crude lipid mixtures without prefractionation, we investigated alternative matrixes that can suppress phospholipid ion and enhance cationization of TAGs. We found an aqueous solution citrate-capped gold nanoparticles (AuNPs)...
Sensitivity is an important factor determining successful mass spectrometry (MS) analysis of metabolome, protein, drugs, and environmental samples. Currently, nanoelectrospray ionization (ESI) widely used as a sensitive method. However, application nano-ESI limited to polar molecules there no atmospheric pressure technique developed that can be for MS low- nonpolar compounds with sensitivity match nano-ESI. Herein, we propose paper spray chemical (PSCI) analyze aromatic high sensitivity....
Phenols are significant environmental endocrine disruptors that can have adverse health effects on exposed individuals. Correlating phenol exposure to potential implications requires the development of a comprehensive and sensitive analytical method capable analyzing multiple phenols in single sample preparation run. Currently, no such is available for classes due electrospray ionization (ESI) limitations concurrent lack sensitivity certain phenols, particularly alkylphenols. In this study,...
A goal in recombinant protein production using Chinese hamster ovary (CHO) cells is to achieve both high specific productivity and cell density. Addition of glucose the culture media necessary maintain growth viability. We varied concentration from 5 16 g/L found that although CHO-DG44 increased with level, integrated viable density decreased. To examine biological basis these results, we conducted a discovery proteomic study grown under batch conditions normal (5 g/L) or (15 over 3, 6, 9...
We developed a modified paper spray ionization (PSI) platform, named as cone (PCSI), for direct mass spectrometric analysis of raw solid samples. The major modification from conventional PSI was the geometry base: PCSI uses triangular-pyramidal-shaped tip instead planar triangular-shaped one. This three-dimensional serves sample container, an in situ solid-liquid extraction chamber, analyte transport channel, well electrospray tip. Unlike spectrometry (MS), weighing with relatively low...
Pulvomycins B–D (1–3) were discovered from an estuarine Streptomyces strain along with the known pulvomycin (4). The 22-membered macrocyclic lactone structures of 1–3 determined based on interpretation NMR, UV, and MS data, modified Mosher's method, Kishi's bidentate chiral solvent NMR spectroscopy. Genomic analysis bacterial revealed biosynthetic gene cluster enabled us to propose trans-acyltransferase polyketide pathway. Pulvomycin D displayed potent cytotoxic activity against various...
A genomic and spectroscopic signature-based search revealed a cycloaromatized enediyne, jejucarboside (1), from marine actinomycete strain. The structure of 1 was determined as new cyclopenta[a]indene glycoside bearing carbonate functionality by nuclear magnetic resonance, high-resolution mass spectrometry (MS), MS/MS, infrared spectroscopy, modified Mosher's method. An iterative enediyne synthase pathway has been proposed for the putative biosynthesis analysis. Jejucarboside exhibited...
Common saprophytic fungi are seldom present in Protea infructescences, which is strange given the abundance of mainly dead plant tissue this moist protected environment. We hypothesized that absence common infructescences could be due to a special symbiosis where presence microbes producing antifungal compounds protect infructescence. Using culture based survey, employing selective media and vitro assays, we isolated antibiotic actinomycetes from repens P. neriifolia two geographically...
Many studies have analyzed nicotine metabolites in blood and urine to determine the toxicity caused by smoking, assess exposure cigarettes. Recently, hair nails been used as alternative samples for evaluation of not only do they reflect long-term but are also stable easy collect. Liquid-liquid or solid-phase extraction has mainly detect biological samples; however, these disadvantages, such use toxic organic solvents complex pretreatments. In this study, a modified QuEChERS method was...
Abstract Mass spectrometric imaging has been utilized to localize individual astrocytes and obtain cholesterol populations at the single‐cell level in laser desorption ionization (LDI) with colloidal silver. The silver ion adduct of membrane‐bound was monitored detect cells. Good correlation between mass optical images different cell densities indicates ability perform studies abundance. feasibility quantification is confirmed by agreement LDI‐MS signals results from a traditional enzymatic...