세파졸린의 산-염기의 거동

이동선,김수현,이윤중 서울여자대학교 자연과학연구소 1990 자연과학연구논문집 Vol.1 No.-

항생물질 cefazolin(CZH)의 산-염기 해리반응에 관해 실험하여 다음과 같은 결론을 얻었다. 1. 전위차법으로 25℃에서 측정한 CZH의 pKa 값은 3.78(±0.05) 이었다. 전도도법으로 측정한 경우 pKa=3.75였으며, [CZNa]/[CZH] = 1.00의 완충용액으로 측정하였을 때에는 pKa = 3.41이었다. 2. CZNa+CZH 혼합용액의 전기 전도도는 [CZNa] 농도가 증가될수록 공통이온외 영향으로 약간씩 감소되었다. 3. CZH의 용해도는 92.8mg/100mL이고, 해리도는 0.4650으로 산출되었다. 4. CZH의 pKa 값은 5~50℃ 범위에서 커다란 변화가 없었다. 5. CZH 산해리반응을 열역학적으로 고찰할 때, ΔG°=+19.995kJ/mol이었다. 따라서 CZH 외 난용성을 증명할 수 있었다. 6. 산-염기 분율조성을 고찰한 결과 pH<3.78의 수용액중에서는 산성형 CZH가 주된 화학종이고 pH>3.78인 용액중에서는 염기형인 CZ^(-)가 주된 화학종임을 알았다. 7. 5% 포도당 주사액중에서는 CZH가, Hartman용액중에서는 CZ^(-)가 주된 화학종이며, 생리식염 주사액중에서는 두 화학종이 비숫하게 분포하였다. 8. 생체액중에서의 CZH거동을 고찰한 결과 동맥혈, 정맥혈, 안방수, 누액, 십이지장, 회장, 소장 등에서는 99%이상 CZ^(-)형태로 분포하고, 위장에서는 약 99%가 CZH형태로 분포하리라 추정되었다. 9. UV 및 IR 흡광특성은 CZNa가 CZH에 비하여 장파장 이동을 나타내었다. The purpose of this study was to determine the acid dissociation constant of cefazolin antibiotics potentiometrically and conductometricaliy, and to identify the principal species in parenteral infusions and body fluids with different pH values. The pKa of cefazolin was 3.78(±0.05) at 25℃, and the pKa value of cefazolin was almost constant at temperature range of 5~50℃. As the concentration of basic form in the mixture of cefazolin(CZH) and cefazolin sodium(CZNa) increased the conductance decreased still further because of the common ion effect. The computed solubility of CZH was 92.8mg/100mL, the fractrion of dissociation a was found 0.4650. The low solubility was demonstrated thermodynamically. The Gibb's energy change for the dissociation was +19.995kJ/mol, reaction is disfavored. The acidic species(CZH) was the predominant form at pH<3.78, the basic species(CZ^(-)) was the principal form at pH>3.78. The results of pH measurement it was assumed that CZH was major in 5% dextrose inj., CZ^(-) in Hartman's solution, and CZH and CZ^(-) existed almost equally in saline solution. It was also assumed that the major form was basic in aqueous humor, blood venous, duodenum, ileum distal, lacrimal fluids, and intestine microsurface, while acidic in the stomch. UV and IR spectra of the basic form, CZ was showed bathochromic shift.

Chromatography에 의한 동물 담즙 中 담즙산류의 分析

李允中,辛昌鎬 成均館大學校 科學技術硏究所 1987 論文集 Vol.38 No.1

The separation and quantitation of bile acids in bile juices have been useful for the study of physiology and kinetics of gallbladder and enterohepatic circulation. Various analytical methods for separation of bile acids were reported by many authors. However, no other method was satisfactory for the separation of bile acids in bile juice. Two available chromatographic methods were used successfully. 1. GC analysis were developed for the rapid, simultaneous separation of free bile acids as their trifluoroacetyl, or trifluoroethyl ester to increase the sensitivity. The procedure involves derivatization of bile acid under vacuum at 30∼40℃ after rapid extraction using sep-pak C_18 cartridge and the derivative then is chromatographed on 1.5% silicone DC QF-1 on chromosorb W, (glass column: 4 mm i.d x 1.2 m) using N_2 as mobile phase. 2. HPLC analysis involves direct injection of bile acids after extraction using sep-pak C_18 cartrige. The sample is chromatographed on a Richrosorb RP-8 column(4 mm i.d. x 25 cm) using CH_3CN : 0.03 M(NH_4)_2CO_3(27 : 73), pH 7.5 for bear gall and MeOH : H_2O(70 : 30), PH 3.5 for other animal gall as mobile phase respectively. Also, conjugated bile acids were separated on a Richrosorb RP-8 column using CH_3CN : 0.03M (NH_4)_2CO_3(31 : 69), pH 3.5 as mobile phase for bear and chicken gall. The described methods are expected to be applied to quality assurance of pharmaceutical product containing bile acid, bear gall and other animal gall.

輸入家電製品 選好度에 關한 硏究 : 電氣 保溫 밥솥을 中心으로 with Special Reference to the Electric Cooker

李允中 연세대학교 경영대학원 1991 經營論叢 Vol.25 No.2

1-Bromoacetylpyrene 誘導體化劑를 利用한 Carboxyl基 含有成分의 分析에 관한 硏究(Ⅲ) : 生藥成分의 HPLC에 依한 定量 Determination of Carboxylic acids in Crude drugs by HPLC

李允中,曺正吉,丁海秀,嚴東玉 成均館大學校 科學技術硏究所 1988 論文集 Vol.39 No.2

A highly sensitive and selective fluoresence high-performance liquid chromatography using 1-bromoace-tylpyrene as a pre-labelling reagent was applied to the determination of cinnamic acid and glycyrrhetic acid at p mol level. The optimum conditions for the derivatization such as concentrations of KOH, 18-crown-6, and 1-bromoacetylpyrene, reaction temperature and reaction time were investigated. The derivatives were separated on a reversed phase column using the mixture of acetonitrile, methanol and water as the mobile phase. The effluent was menitored by fluorometer. Linearities of calibration curve were obtained between 0.5 p mol and 2.0 p mol. The detection limit of cinnamic acid and glycyrrhetic acid was 0.05 p mol in a 20 ㎕ of injection volume.

高速液體 Chromatography에 의한 製劑中 Crotamiton의 分離定量에 관한 硏究

李允中,曺正吉,李東宣,尹汝生,金在鉉 成均館大學校 科學技術硏究所 1983 論文集 Vol.34 No.1

The method for rapid determination of crotamiton in ointment and action was established by using reverse phase high performance liquid chromatography. First, crotamiton in ointment (or lotion) was extracted with methanol and 20㎕ portion of the extracted solution was injected into the column. The effluent was monitored by an ultraviolet detector at 254 um. On a μ-Bondapak C_18 column(3.9 mm i. d x 30cm) with an eluent of MeOH/H_2O=55/45, a sufficient separation of crotamiton, preservatives, and minor components was obtained. The proposed procedure provided an accurate, sensitive, and rapid estimation, and a good , ability suggesting a suitable assay method for crotamiton in pharmaceuticals.

새로운 HPLC용 형광유도체화제인 1-(N,N-dimethylamino)pyrene-6-sulfonyl chloride를 이용한 아민화합물의 분석

이윤중(Yoon Joong Lee),김용희(Yong Hee Kim),조정길(Jeung Kil Cho) 대한약학회 1991 약학회지 Vol.35 No.4

A new fluorescent derivatizing reagent was developed to be used in HPLC for the trace determination of primary and secondary amines. This new reagent, 1-(N,N-dimethylamino)pyrene-6-sulfonyl chloride, was synthesized by the chlorination of sodium 1-(N,N-dimethylamino)pyrene-6-sulfonate which was obtained from 1-(N,N-dimethylamino)pyrene after sulfonation. Ephedrine and norephedrine were derivatized quantitatively by this reagent. The optimum conditions for the derivatization such as pH, reagent concentration, reaction time and reaction temperature ware examined. The structures of derivatives were identified by IR, 1H-NMR and MS methods. The fluorescence properties and the stability of the derivatives were examined. The derivatives were separated on silica column with an isocratic elution using the mixture of n-hexane and ethylacetate and monitored by fluorescene detector. Linear calibration curves were obtained and detection limits in a 10 mcl injection volume were 5 picomole for ephedrine and norephedrine.

高速 液體 Chromatography에 의한 Prostaglandin F_2α및 E_2定量에 관한 硏究

李允中,李東宣 成均館大學校 科學技術硏究所 1985 論文集 Vol.36 No.1

Prostaglandin F_2α and E_2 are being applied for induction of labor, termination of first or second trimester pregnancies and postpartum atonic uterine bleeding. Though various analytical methods for quantitation of prostaglandins were reported elsewhere, the development of a more sensitive, rapid and progressive method has long been desired. This study was conducted to quantitate PGF_2α and PGE_2 simultaneously by high performance liquid chromatography after p-bromophenacylation of Sep-Pak C_18, cartridge extracts. The results were as follows: 1. A high performance liquid chromatographic analysis were developed for the rapid, simultaneous separation and quantitative recovery of PGF_2α, PGE_2 as their p-bromophenacyl esters to improve chromatographic properties and to detect them at 254 nm. The procedure involves p-bromophenacylation of PGF_2α and PGF_2 under N, N-diisopropyl ethylamine catalyst after rapid extraction using Sep-Pak C_18 cartridge, which is then chromatographed on μ Bondapak column (8 mm i.d. x 10 cm) using acetonitrile : water(1 : 1) as mobile phase. 2. HPLC peaks of PGF_2α and PGE_2 were observed at 10.8 min. and 12.3 min., respectively. Linear calibration plots of peak area versus PGF_2α and PGE_2 concentration were obtained over the range of 0.1-1.2㎍/㎕. This method enables to determine simultaneously PGF_2α, and PGE_2, thus shortening the assay time in comparison with that of p-nitrophenacylation. 3. p-Bromophenacylation was complete in about 40 min. at room temperature, and aliquots of the reaction mixtures were capable to be analyzed directly by HPLC. 4. The recovery in the concentration of 20 ㎍-4 mg prostaglandin was 99% by single Sep-Pak C_18 cartridge(1 cm i.d. X 1 cm) extraction with 10 ml ethanol(over 70 % ). The amount of prostaglandin was measured by ultra-violet spectrophotometry and fluorometry. For the Sep-Pak C_18 extraction, the optimum pH range was acidic(pH 3. 0). The present method allowed to obtain a clean extract from various samples suitable for HPLC analysis.

형광유도체화제로 Bansyl-Cl을 이용한 Dopamine, Norepinephrin의 HPLC분석법에 관한 연구

이윤중,이강민,김영도 成均館大學校 科學技術硏究所 1992 論文集 Vol.42 No.2

A rapid and high sensitive HPLC method for the determination of dopamine and norepinephrine is described. 5 -Dibutyl-aminonaphthalene-1-sulfonyl chloride (bans yl-Cl) was used as a pre-column fluorescent derivatizing reagent for HPLC determination of the two compounds. The optimal conditions for the derivatization of dopamine and norepinephrine with bansyl-Cl such as pH, reaction time, reaction temperature, and the amount of bansyl-Cl were described. The structures of bansyl derivatives were identified by Infrared and ^1H-NMR spectroscopy. The bansyl derivatives were separated on Radialpak^TM NH_2 column using the mixture of cyclohexane and ethyl acetate as the mobile phase and monitored by fluorescence detector. Linearity of calibration curve was obtained and the detection limits in a 5 μl injection volume were 2.5ng/ml, respectively.

大韓藥典 第2 改訂版의 內容

李允中 성균관대학교 1968 成均藥學 Vol.9 No.-

韓國産 大麻中 Tetrahydrocannabinol의 時期別 含量 變化에 關한 硏究

李允中,柳弘一 成均館大學校 1974 論文集 Vol.19 No.-

Marihuana containing tetrahydrocannabinol, a psychotomimetially active component, is being abused to lead serious social problems over the world these days. To obtain some scientific data to cope with various kinds of illegal traffic or abuse, I cultivated cannabis plants at N.I.H. in Seoul and also Pusan University in 1972 for about 27 weeks to each. And I studied on seasonal variation of tetrahydrocannabinol cantent of Korean cannabis. Tetrahydrocannabinol was separated and determined by this layer chromatography No. 6,7,8,9,10 and colorimetry respectively. The followings are summarization of accomplishments. 1. This data shows that Tetrahydrocannabinol content in the leaves of cannabis plants materials is richest just before blossomming approximately from 7th till 22nd of July. 2. The comparison between green leaves and maple leaves of cannabis shows that both contain roughly similar acount of tetrahydrocannabinol. 3. The comparison between male and female cannabis shows that both sexes contain similar amount of Tetrahydrocannabinol, which is the same as that reported by A. Ohlsson and the Report Vol. No. 8. by N.I.H. Korea. 4. Tetrahydrocannabinol is most abundant folwering tops in comparison with other parts of cannabis, and stem, seed, root hardly contain Tetrahydrocannabinol. 5. My data shows that there is usually a little difference in Tetrahydrocannabinol content according to different regional groups. 6. Tetrahydrocannabinol content in leaves is the mest important, considering that other parts of cannabis contain Tetrahydrocannabinol. Therefore I can say merely from the keeping control over various kind of illegal traffic of abuse point of view, it is more effective for us to control the leaves of cannabis.