• Analytical Science and Technology
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• v.26 no.4
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• pp.228-234
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• 2013

Methamphetamine is an amine-containing illegal drug and is distributed unlawfully in South Korea. Finding a rapid, convenient and semi-quantitative determination method for methamphetamine is a very important issue in the area of forensic drug testing. As an effort to develop new screening method, the reactions between three organic compounds which are structurally similar to methamphetamine and N-(9-fluorenylmethoxycarbonyloxy) succinimide (FMOC-NHS) were performed on silica gel ($SiO_2$) TLC plates. Three reference compounds were synthesized and used for the identification, comparison and study of the limit of detection (LOD) of the products obtained from a direct reaction on a TLC plate. As a result, FMOC-NHS as a derivatization reagent generated compounds containing highly UV-active functional groups on the TLC plate after reacting with primary- and secondary amines. In the experiment 2D the LOD of amines was in the range of 0.045 and 0.01 mg/mL ($2{\mu}L/spot$), and in 1D the LOD was in the range of 0.002 and 0.007 mg/mL ($2{\mu}L/spot$). The LODs of the compounds tested were dependent on the concentration of the derivatizing reagent.

• Analytical Science and Technology
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• v.17 no.4
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• pp.322-336
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• 2004

The improved derivatization technique of tamoxifen metabolite in human urine is described for the acylation method that they are substituted by derivatization reagent like acyl anhydride for use of gas chromatography/mass spectrometry. The hydroxyl group of tamoxifen metabolite was derivatized by trifluoroacetic anhydride (TFAA), pentafluoroacetic anhydride (PFPA) and heptaflorobutylic anhydride (HFBA). It was investigated to the gas chromatography/mass spectrometry (GC/MS) technique use negative ion chemical ionization (NCI), positive ion chemical ionization (PCI) and electron impact (EI). In acylation of the metabolites of tamoxifen, the effective reaction temperature and time were shown to be at $50^{\circ}C$ for 30 min. The 4-hydroxytamoxifen, which is known to major metabolite of tamoxifen, was not detected in human urine, whileas the hydroxymethoxytamoxifen was detected. We thought that this result was from the single dose of tamoxifen.

• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.225-233
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• 2020

By the standards and specifications for hygiene products, three test methods for formaldehyde are specified for each item type of hygiene product. After derivatization using acetylacetone and 2,4-dinitrophenylhydrazine (2,4-DNPH), formaldehyde is analyzed by spectrophotometer and high-performance liquid chromatography (HPLC). Validation of the three test methods was performed on tissue, diaper lining and waterproof layer, and panty liner products. The results of linearity (R²), limit of detection (LOD), limit of quantification (LOQ), recovery rate (%) and reproducibility (%), showed that all three methods are suitable for analyzing formaldehyde in hygiene products. After derivatization with 2,4-DNPH and cetylacetone, formaldehyde was analyzed at 0, 3, 6, 9, 24 and 48 hours by HPLC. Formaldehyde derivatized with 2,4-DNPH showed no statistically significant change in formaldehyde peak area over time (P>0.05). But, acetylacetone-derivatizated formaldehyde showed a negative correlation coefficient (r) over time (P<0.01). We investigated the residual amounts of formaldehyde in 205 hygiene products distributed in Busan. Among 74 disposable diaper products tested, 73 had low concentrations of formaldehyde (0.13-29.87 mg/kg). Moreover, formaldehyde was not detected in any of 78 tissue, 27 disposable paper towel, 12 disposable dishcloth, 7 paper cup, one brand of paper straw and 6 disposable napkin products.

• Analytical Science and Technology
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• v.18 no.6
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• pp.453-459
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• 2005

Phenol compounds in water were simultaneously analyzed by extractive derivatization. Aqueous solution was controlled to pH 13 with sodium hydroxide, and then $500{\mu}L$ of benzoyl chloride was added to the solution. The solution was shaken for 15 minutes and extracted with diethyl ether and then analyzed using GC/MS-SIM. The calibration curves of phenolic compounds in the range of 0.05 to $5.0{\mu}g/mL$ showed a good linearity having the correlation coefficient of $r^2=0.9915$ and standard deviation of ${\leq}8.5%$, respectively. The recoveries by this method ware 58.4-114.0%.

• The Korean Journal of Pesticide Science
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• v.9 no.2
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• pp.159-165
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• 2005

A sensitive derivatization method by using the TFE/TFAA as derivative reagent is proposed for the determination of acidic herbicides in water, by using this method, method detection limits are improved by 10 times and sample volumes are decreased by 5 times compared with other methods such as U.S. EPA and SPEED 98. And also, in order to suggest higher creditable standard operating procedure (SOP), intra- and inter-lab validation test carried out by four laboratories include our lab. The results of intra and inter-lab validations in same experimental conditions show good linearity in given range of concentrations as a $0.1{\sim}10.0$ ng/ml, and range of accuracies and precisions show $-20.5{\sim}12.2$ bias%, $0.55{\sim}24.48%$ (for intra-lab validation) and $-6.66{\sim}0.80 bias%$, $1.92{\sim}13.86%$ (for inter-lab validation), respectively.

• Analytical Science and Technology
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• v.6 no.1
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• pp.9-19
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• 1993

Fatty acid salts derived from soap can be transferred into a typical derivative with p-bromophenacyl bromide using crown ether, a catalizer by the solid-liquid phase transfer reaction in nonpolar, aprotic solvents and separated by the reverse phase high performance liquid Chromatography (RP-HPLC) and determined using UV detector. The minimal limit of detection was defined at approximately 10~50ng in accordance with the chain length. The derivatization reaction in the presence of EDTA can be applied mot only to the calcium salts but also to the other various metal salts. The recoveries of fatty acid derivatizations in the absence and presence of the midium containing the yeast extract were obtained $95.4{\pm}1.2$, and $85.2{\pm}2.4%$ respectively. The analytical method would be applicable to determine the biodegradation of fatty acid salts in nature as well as in artificial condition such as shaker flask-medium method.

• Analytical Science and Technology
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• v.28 no.2
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• pp.79-85
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• 2015

A preliminary experiment was performed to develop a fast, convenient, and economical semi-quantitative method of analyzing amphetamine-like amines from images of derivatives. These were generated from the reaction (in situ, co-spot) of three amphetamine-like compounds with three derivatization reagents on a TLC plate. The attempt was made to optimize the reaction conditions for an efficient derivatization reaction, and TLC images taken by a digital camera were analyzed using two types of image analysis program (CP Atlas 2.0 and ImageJ) for repeatability (RSD, %) and linearity (R²). Then, their results were compared. For efficient derivatization, the reaction conditions needed to be modified. The results of image analysis of each of the samples at two different concentrations (0.5 mg/mL and 0.01 mg/mL) showed that the RSD values for reaction repeatability were in the range of 0.69-5.50%. From the calibration curves between the area of the derivative and the concentration of amines, the R² values (R² > 0.9906) for good linear correlation were found to be high, in a concentration range of 0.1-0.005 mg/mL of amines. In addition, the two programs demonstrated little difference in the analysis of repeatability and linearity of the derivatization, so that the current method has the potential to be used for the semi-quantitative analysis of amines.

• Journal of Food Hygiene and Safety
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• v.16 no.1
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• pp.61-65
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• 2001

To investigate the optimum condition of 3-monochloro-1, 2-propanediol(MCPD) analysis, gas chromatography with electron capture detector was used. Determination of MCPD derivatized with phenylboric acid was more effective than that of underivatized MCPD. In derivatization of MCPD with phenyl boric acid, there were no significantly different between boiling for 2min at 9$0^{\circ}C$ and vortexing for 5min at room temperature. Extrelut column was suitable for extraction of MCPD diluted in 20% NaCl solution and recovery rates were higher than direct extraction of MCPD with ethyl acetate. But, the method of direct extraction of MCPD with ethyl acetate was useful for rapid ants qualitative analysis. The sample extracted in soysauce(ganjang) was derivatized with phenylboric acid and analyzed by gas chromatography-mass selective detector. That was confirmed as MCPD-phenylboronate.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2006.11b
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• pp.397-409
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• 2006

연구결과는 학술적인 논문, 기술의 기반이 되는 특허, 기술이 체화된 상품 등 다양한 방법으로 도출되고 있다. 현재까지 연구 성과를 측정하는데 있어서 수치로 표시되는 정량적인 평가는 용이하게 활용하고 있다. 하지만 질적인 우수성을 평가하기 위한 정성적인 방법은 많은 연구를 필요로 한다. 각기 다른 목적이나 용도로 만들어진 평가지표나 방법론이 적절하게 적용하여 평가지표로 적용되어 지기는 힘든 상황이다. 특히 연구자나 기관 등의 평가 시 연구논문을 활용한 계량정보기법을 근간으로 하는 다양한 방법이 많은 연구자들을 통해 제시되고 있다. 또한 학술적인 논문뿐아니라 산업으로 대표되는 특허의 평가시도 유사한 방법을 활용하고 있다. 문헌의 경우는 SCI DB를 활용하여 정성적인 부분을 대체하고 있다. 하지만 산업으로 대표되는 특허의 정성 평가는 많이 활용하지 못하고 있다. 이에 특히 문헌 및 특허의 인용정보를 대상으로 최근 제안되고 있는 연구 성과 지표인 h-지수 등을 활용하여 사례를 분석하여 보고자 한다.

• Analytical Science and Technology
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• v.19 no.1
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• pp.107-114
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• 2006

Early diagnosis and medical intervention are critical for the treatment of patients with metabolic disorders. A rapid analytical method was developed for simultaneous quantification of organic acids and amino acids in urine without labor-intensive pre-extraction procedure showing high sensitivity and specificity. A new method consisted of simple two-step trimethylsilyl (TMS)-trifluoroacetyl (TFA) derivatization using GC/MS-selective ion monitoring (SIM). Filter paper urine specimens were dried under nitrogen after being fortified with internal standard (tropate) in a mixture of distilled water and methanol. Methyl orange was added to the residue as indicator reagent. Silyl derivative of carboxylic functional group was followed by trifluoroacetyl derivative for amino functional group. N-methyl-N-(trimethylsilyl-trifluoroacetamide) and N-methyl-bistrifluoroacetamide were consecutively added and heated for 15-20 min at $65^{\circ}C-70^{\circ}C$, for TMS-TFA derivative, respectively. This reactant was analyzed by GC/MS-SIM. Linear dynamic range showed 0.001-50 mg with the detection limit of (S/N=3) 10-200 ng, and the quantification limit of 80-900 ng in urine. Correlation coefficient of regression line was 0.994-0.998. When the method was applied to the patients 'urine, it clearly differentiated the normal from the patient with metabolic disorder. The study showed that the developed method could be the method of choices in rapid and sensitive screening for organic aciduria and amino acidopathy.