• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.11c
• /
• pp.525-532
• /
• 2000

A new spectroscopic method for pesticide residues detection on agricultural products was developed. The general determination methods are high performance liquid chromatography (HPLC), gas chromatography (GC) or GC-mass spectrometry. They have provided relatively good detection limit and accuracy with complicated and time-consuming (5hrs above) procedures. In addition freshness is very important for evaluating qualities of agricultural products. This requires a simple and fast method for detection of pesticides. Reflectance, transmittance and fluorescence spectrometry of pesticides were tested using UV range because most of pesticides contain conjugation band in the molecular structures. Fluorescence spectrometry showed better sensitive to detect pesticide residues than did reflectance and transmittance spectrometry. Intensity and shape of fluorescence spectra showed different patterns with different structures of pesticides. Detection limit for fluorescence spectrometry was 0.1 ppm to 10 ppm depending on the structures of pesticides. Application of fluorescence spectrometry appears to be an easy method for detection of pesticide residues on agricultural products.

• Archives of Pharmacal Research
• /
• v.13 no.2
• /
• pp.174-179
• /
• 1990

Second derivative (D2) spectrometry using ion-pair extraction technique was development for the determination of total glycyrrhetic acid (GA) in Glycyrrhizae Radix, Glycyr-rhizin (G) obtained from Glycyrrhizae Radix was hydrolyzed into GA in 2 N-HCI and methanol (1:1) and extracted from aqueous phase in the form of an ion-pair complex with tetrapentylammonium bromide (TPA) as a counter ion. Maximum D2 amplitude (Z value) was obtained when 1000-fold or greater molar ratio of TPA was used at pH 11. Reaction an effective extraction solvent of the ion-pair complex. The linearity of standard curve of ion-pair GA was obtained in the range of 4.120 $\mu$g/ml as GA. Assayed contents of GA in dry powder by D2 UV spectrometry and HPLC method were 5.31 $\pm$ 0.04% and 5.20 $\pm$ 0.008%, respectively.

• Mass Spectrometry Letters
• /
• v.3 no.4
• /
• pp.101-103
• /
• 2012

The ultraviolet (UV) degradation products of photochromic naphthoxazine and naphthopyran derivatives in acetonitrile were separated and identified using liquid chromatography-mass spectrometry (LC-MS). Photodegradation resulted in oxidation of products.

• Journal of the Korean Society for Precision Engineering
• /
• v.33 no.9
• /
• pp.699-706
• /
• 2016

Assay of biomolecules based on absorption spectroscopy is a sensitive, minute, quantitative, rapid and real-time process. UV-vis spectrometry has inherent advantages for use in analytical applications. To reduce the consumption of scarce samples, a new generation of miniaturized UV-vis spectrometric systems has been developed. This study determined empirically and through simulations the feasibility of assaying biomolecules by means of UV-vis spectrometry. This paper also reports a fully integrated portable micro-detection equipment system that utilizes a micro-optical path for analysis of micro-volume samples.

• KEPCO Journal on Electric Power and Energy
• /
• v.7 no.2
• /
• pp.309-316
• /
• 2021

For the detection of the state of charge in VRFB-ESS, the analyses of UV-Visible spectrometry and the measurements of potential between the anolyte and catholyte were used in parallel. This paper includes the production of 4-valant ion from VOSO4 powder, 3- and 5-valant ions from electrochemical charge of 4-valant ion and 2-valant ion from 3-valant ion. It also includes the analyses of these valance ions and unknown electrolyte at any time using UV-Visible spectrometry. Through the analyses of the valance ions in samples, the SOCs of the samples at any charge-discharge times were verified.

• Mass Spectrometry Letters
• /
• v.13 no.4
• /
• pp.95-105
• /
• 2022

Amatoxin-induced mushroom poisoning starts with nonspecific symptoms of toxicity but hepatic damage may follow, resulting in the rapid development of liver insufficiency and, ultimately, coma and death. Accurate detection of amatoxins, such as α-, β-, and γ-amanitin, within the first few hours after presentation is necessary to improve the therapeutic outcomes of patients. Therefore, analytical methods for the identification and quantification of α-, β-, and γ-amanitin in biological samples are necessary for clinical and forensic toxicology. This study presents a literature review of the analytical techniques available for amatoxin detection in biological matrices, and established an inventory of liquid chromatography (LC) techniques with mass spectrometry (MS), ultraviolet (UV) detection, and electrochemical detection (ECD). LC-MS methods using quadrupole tandem mass spectrometry, time-of-flight mass spectrometry, and orbitrap MS are powerful analytical techniques for the identification and determination of amatoxins in plasma, urine, serum, and tissue samples, with high sensitivity, specificity, and reproducibility compared to LC with UV and ECD, enzyme-linked immunoassay, and capillary electrophoresis methods.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.9
• /
• pp.3119-3121
• /
• 2012

• Mass Spectrometry Letters
• /
• v.12 no.3
• /
• pp.118-124
• /
• 2021

Many previous studies have focused on revealing the harmfulness of microplastic particles, whereas very few studies have focused on the effects of chemicals, particularly photooxidation product. In this study, products of photodegradation from expanded polystyrene (EPS), compounds produced by photolysis by ultraviolet (UV) light, were investigated. EPS was directly irradiated and photolyzed using a UV lamp, and then the extracted sample was analyzed using high-resolution mass spectrometry (HRMS). Multiple ionization techniques, including electrospray ionization, atmospheric pressure chemical ionization, and atmospheric pressure photoionization, were used. In total, >300 compounds were observed, among which polystyrene monomer, dimer, and oxidized products were observed. In this work, the data presented clearly demonstrate that it is necessary to identify and monitor oxidized plastic compounds and assess their effect on the environment.

• Proceedings of the Korean Society of Toxicology Conference
• /
• 2003.10b
• /
• pp.131-131
• /
• 2003

Benzophenone is an UV-absorbing agent that has been used in industry and medicine for more than 30 years. Its twelve derivatives, designated benzophenone-1 through benzophenone-12, are widely used today in cosmetic products as a photostabilizer, a sunscreen in lotions, and hair sprays to protect the skin and hair from UV irradiation.(omitted)

• Journal of Korean Society on Water Environment
• /
• v.28 no.6
• /
• pp.902-910
• /
• 2012

The photodegradation characteristics of 30 pharmaceuticals were investigated by batch experiments using Ultraviolet (UV) reactor. The investigated pharmaceuticals include antibiotics, analgesics and antiarrhythmic agents etc. Tested water was prepared by simultaneously spiking 30 pharmaceuticals into pure water, and each experiment was conducted using 3 types of UV lamps. As a result, batch experiments showed that reactions of all the investigated pharmaceuticals followed pseudo-first order reaction regardless of the applied UV lamps. Among the pharmaceuticals, Cyclophosphamide, 2-Quinoxaline carboxylic acid and Clarithromycin proved to be the most UV-resistant compounds. Contrarily, Ceftiofur, Diclofenac and Ketoprofen were easily degraded by all the UV lamps. Dissolved organic carbon (DOC) concentration hardly changed although the concentration of the pharmaceuticals concentration gradually decreased with time, indicating that the degradation of parent pharmaceuticals may produce their intermediates during UV treatment.