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.

國內 주부들의 輸入製品 선호도

이윤중 한국마케팅연구원 1993 마케팅 Vol.27 No.10

CTMAC에 依한 造血劑中의 微量鐵分의 吸光光度定量

李允中,李東宣 成均館大學校 1975 論文集 Vol.20 No.-

A method is described for the spectropohtometric determination of iron with cetyltrimethyl ammonium chloride(CTMAC) tha reacts with ferrithiocyanate chelate anion to form precipitate extractable in isoamylalcohol. As a result of experimentation, water insoluble red complex is produced by the reaction of the ferric ion with thiocyanate in the presence of cation surfactant just ad CTMAC. And the Fe(Ⅲ)-SCN-CTMAC associated complex is extracted from aqueous phase into organic phase(isoamylalcohol). The extracted species has an absorption maximum at about 495 nm, with a constant absorbance in the pH range from 1.0 to 2.0. It is found that the wave length of maximum absorption represents the bathochromic shift by the addition of CTMAC and that this method is more sensitive than the most widely used ferrithiocyanate procedure. Beer's law is obeyed up to 4 mcg/㎖ ferric ion in aqueous phase, for the absorbance of the associated complex under the optimum condition of pH, reagent concentrations and shaking time. This method can be used to the analysis of iron in commercial hematopoietics.

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.

1-(N,N-dimethylamino)pyrene-6-sulfonyl chloride를 형광유도체화체로 이용한 Norepinephrine의 HPLC 분석에 관한 연구

이윤중,김용희,이혜숙,박광신 성균관대학교 약학연구소 1991 成均藥硏論文集 Vol.3 No.1

Abstract-A rapid and high sensitive HPLC method for the determination of norepinehrine is described. 1-(N,N-dimethylamino)pyrene-6-sulfonyl chloride (DAPS-Cl) was used as a pre-column fluorescent derivtizing reagent for HPLC determination of norepinephrine. The optimal conditions for the derivatization of norepinephrine with DAPS-Cl such as reaction temperature, reaction time, and the amount of DAPS-Cl were described. The structure of derivative was confirmed from ^1H-NMR spectra. The DAPS-NE derivative was separated on a reverse phase column(ODS-1) using the mixture of acetonitrile and 0.05 M phosphate buffer (pH 4.5) as the mobile phase and monitored by fluorescence detector. Linearity of calibration curve was obtained and the ddetection limits in a 10㎕ injection volume was 200 fmol.

HPLC용 형광유도체화제인 1-(N,N-dimethylamino)pyrene-6-sulfonyl chloride를 이용한 GABA와 Glutamate의 HPLC분석에 관한 연구

이윤중,김용희,강동호,박귀례 성균관대학교 약학연구소 1991 成均藥硏論文集 Vol.3 No.1

Abstract-Fluorescent derivatives of amino acid neurotransmitter such as GABA and glutamate were synthesized using 1-(N,N-dimethylamino)pyrene-6-sulfonyl chloride (DAPS-Cl) as a derivatizing reagent. GABA and glutamate were derivatized quantitatively into fluorescent compounds by reacting with DAPS-Cl. The optimal conditions for the derivatization of GABA and glutamate with DAPS-Cl were estimated such as pH, reaction temperature and time, and the amount of DAPS-Cl. The derivatives were separated on a reverse phase column with a gradient elution using the 30 mM phosphate buffer and acetonitrile, and monitored by fluorescence detector. Calibration curves for GABA and glutamate exhibited good linearty over 1∼5 pmol. GABA and glutamate in hippocampus of rat brain were determined. After postmortem of rat brain, GABA increasing and glutamate decreasing in hippocampus were prevented 3-mercaptopropionic acid and microwave application.

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.

大韓藥典 第2 改訂版의 內容

李允中 성균관대학교 1968 成均藥學 Vol.9 No.-

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.