• 대한화학회지
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• 제39권4호
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• pp.257-265
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• 1995

시중에 시판되고 있는 우유를 전처리하여 이 우유에 포함된 유리 아미노산을 dansyl-chloride로 유도체화시켜 C-18 컬럼을 이용한 역상 LC법으로 분리한 다음 표준물 첨가법으로 정량했다. 미량의 D-아미노산의 분리에서는 LC의 Column-Switching System을 이용하였으며 비키랄 컬럼을 통과한 단실 D/L-아미노산에 $Cu(N-benzyl-L-proline)_2$를 이동상에 첨가한 키랄 분리를 수행하여 L-아미노산에서 D-아미노산을 분리 정량했다. 이 방법은 우유시료 중에 존재하는 16가지 아미노산의 정량이 가능하며 이중에 12가지의 D-아미노산이 column switching 방법을 통한 키랄 분리로 정량이 가능하다. 우유 100 mL에 총 유리 아미노선이 41.00 mg 포함되어 있음을 확인했으며, D-아미노산은 D-glutamic acid가 2.05%, D-alanine 2.93%만이 포함되어 있음을 확인했다.

• 대한화학회지
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• 제38권7호
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• pp.502-508
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• 1994

염의 농도가 큰 시료용액중에 미량으로 함유되어 있는 U(VI)과 Th(VI)을 액상크로마토그래피로 동시에 분리, 정량하였다. 약 2ml의 시료를 pH5.5의 0.11M ${\alpha}$-HIBA 용리액과 함께 C_{18}$ 역상농축컬럼에 통과시켜 U(VI)과 Th(VI)을 농축시켰으며, 농축된 이들 원소들을 다시 비활성 C_{18}$ 역상분리컬럼에서 pH3.0의 0.17M ${\alpha}$-HIBA/0.0038 M 1-pentanesulfonate 용리액으로 각각 분리하였다. 분리된 이들 원소들은 Arsenazo III를 사용하는 postcolumn반응으로 검출되었으며, 검출한계는 두 원서 모두 1ppb이었다.

• The Korean Journal of Physiology
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• 제24권2호
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• pp.363-375
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• 1990

The present investigation was performed to purify bombesin-like immunoreactivity (BBS-LI) from the skin of frogs, B. orientalis inhabiting Korea. For extraction of BBS-LI, the fresh skin of 360 g from frogs was immersed in 1,800 ml of 100% methanol and then kept at $4^{\circ}C$ for 5 days. BBS-LI was partially purified by liquid chromatography using an alkaline alumina column followed by a Sephadex G-10 column. BBS-LI was further purified by using sequential HPLC of reversed phase C18 preparation, gel permeation, SP-ion exchange and reversed phase C18 analysis. BBS-LI in fractions of each step was monitored by radioimmunoassay for which bombesin antiserum with a titer of 1 : 188,800 was raised in a guinea pig. Eventually, two different BBS-LI were successfully purified and each BBS-LI showed the following character. 1) BBS-LI was well separated into two peaks in SP-ion exchange HPLC. One (BBS-LI-K1) bound to the column while the other (BBS-LI-K2) did not. 2) BBS-LI-K1, 73.8% of total BBS-LI, was not differentiated from synthetic bombesin in reversed phase C18 analytical and gel permeation HPLC. 3) BBS-LI-K2, 26.2% of total BBS-LI, eluted later than synthetic bombesin in reversed phase C18 analytical HPLC, but it eluted with a retention time identical to that of synthetic bombesin in gel permeation HPLC. 4) The two forms of BBS-LI and synthetic bombesin identically stimulated gastrin release and pancreatic exocrine secretion including volume, protein output and amylase output in anesthetized rats. It is concluded from the above results that the skin of B. orientalis contains two different forms of BBS-LI which are very identical to bombesin immunologically and biologically. In comparison with synthetic bombesin containing 14 amino acid residues, the major form shows quite similar pattern in all HPLC used in the present study, but the minor form exhibits quite different pattern in SP-ion exchange and reversed phase C18 analytical HPLG.

• Journal of Pharmaceutical Investigation
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• 제37권3호
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• pp.187-192
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• 2007

A reversed phase HPLC analysis of atorvastatin (AS) standard solution was performed using diclofenac (DF) as internal standard. Column oven temperature, flow rate and the composition of the mobile phase were varied in order to determine a practical system setup using a C18 column and UV detector. Two C18 columns of different length were compared regarding their influence on the AS peak shape. Based on these preliminary experiments a validation study was performed utilizing a C18 column at $62^{\circ}C$ with a mobile phase consisting of sodium phosphate buffer (0.05 M, pH 4.0), methanol and acetonitrile (40:50:10, v/v/v). The detection limit for AS was $0.1{\mu}g/ml$ and inter- and intra-day calibration curves were linear over a concentration range of $0.2-50{\mu}g/ml$. Accuracy and precision were satisfactory in the AS concentration range of $0.5-50{\mu}g/ml$.

• 약학회지
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• 제37권1호
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• pp.1-8
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• 1993

A procedure for the high-performance liquid chromatographic determination of Nebramycin factors in fermentation broth of Streptoalloteichus hindustanus ATCC 31218 mutant was investigated using pre-column derivatization and LTV detection. The method is based on pre-column derivatization of Nebramycin factors with 2,4-dinitrofluorobenzene(DNFB) in the presence of Tris (hydroxymethyl)aminoethane. The chromatographic separation of derivatives of Nebramycin factors and unknown impurities is achieved using reversed-phase column (NOVA-PAK $C_{18}$, Waters Co.) and AcCN : H$_{2}$O : AcOH (53.0:46.5:0.5) as a mobile phase. The mixture of these derivatives were separated within 35 minutes and the optimum wavelength($\lambda_{max}$ ) of the UV detector was 353 nm. The linearity of response for derivatives of Nebramycin factors is demonstrated for concentrations up to 500 $\mu\textrm{g}$/ml and the relative standard deviation is less than 0.79%. Detection limit was 1.67 ng for the 10 $\mu\textrm{l}$ sample volume employed.

• Archives of Pharmacal Research
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• 제17권5호
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• pp.360-363
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• 1994

Column--swtiching technique with a reversed-phase high performance liquid chromatographic method has been developed for the routine analysis of radioiodinated insulin and its degadation products in biological fluids. The diluted biological samples were loaded onto a precolumn packed with LiChrosorb RP-8 $(25-40{\;}{\mu}m)$ using 0.1% trifuoroacetic acid (TFA) in water as a washing solvent. After valve switching, the concentrated insulins were eluted in the back-flush mode and separated by a W-Porex $C_{18}$ column with a gradient of 0.1% TFA in water and 0.1% TFA in acetonitrile as the mobile phase. The method showed good precision, accuracy and speed with the detection limit of 20 pg/ml. Total analysis time per sample was about 40 min and the coefficients of variation were less than 8, 2%.

• 분석과학
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• 제5권1호
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• pp.63-71
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• 1992

역상 액체 크로마토그래피에 의한 몇 가지 금속-N-Alkylisonitrosoacetylacetone imine 킬레이트의 용리거동을 Novapak $C_{18}$ 분리관을 사용하여 조사하였다. 용리액은 Acetonitrile/Water로 하였으며, 각 금속의 킬레이트의 최적 용리액 조성은 각각 70:30(Pd의 경우), 60:40(Ni의 경우) 및 50:50(Co의 경우)이었으며, 리간드의 alkyl기 종류에 따른 금속 킬레이트의 용리순서는 methyl>ethyl>propyl>butyl 유도체 순이었다. 모든 금속 킬레이트의 log k'값은 $0{\leq}log\;k^{\prime}{\leq}1$의 범위였고, log k'값과 용리액 중 물의 부피분율을 도시한 결과 직선관계가 성립되었다. 또한 뱃치법으로 측정한 분포비(Dc)값의 크기는 금속 킬레이트의 용리순서와 비교적 잘 일치할 뿐만 아니라 Dc값과 k'의 직선관계를 나타냄으로써, 금속 킬레이트의 용리 메카니즘은 주로 소용매성 효과, 즉 소수성 효과에 기인함을 확인하였다.

• 한국축산식품학회지
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• 제40권1호
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• pp.87-95
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• 2020

In this study, we separated and purified lipase inhibitory peptide from fermented milk by Lactobacillus plantarum Q180 with the aim of developing a new functional anti-lipase activity yogurt product. L. plantarum 180 was inoculated into 10% reconstituted skimmed milk and incubated at 37℃ until the pH of the culture reached pH 4.4. The lipase activity was measured using porcine pancreatic lipase. The lipase inhibitory peptides were gradually isolated by ultrafiltration, reversed phase column chromatography (RPC), reversed phase high-performance liquid chromatography (RP-HPLC), and gel permeation high-performance liquid chromatography (GP-HPLC) from the fermented milk by L. plantarum Q180. An ODS-AQ column was used for the RPC, a Vydac C18 column for the RP-HPLC, and a Superdex Peptide HR column for the GP-HPLC. The peptide was composed of Asp, Thr, Ile, Ser, Ala, and Gln, and the anti-lipase activity (IC₅₀) was 2,817 ㎍/mL.

• 대한화학회지
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• 제37권12호
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• pp.1035-1046
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• 1993

몇 가지 iron(III)porphyrin 착화합물을 합성하고, 이들에 대하여 역상 액체 크로마토그래피에서의 최적 분리조건 및 용리거동을 조사하였다. 분리관, 흐름속도, 용리액의 조성 등을 변화시킨 실험에서 분리관은 NOVA-PAK $C_{18}$, 용리액은 methanol/water의 이성분 혼합용매를 적당히 조절하였을 때 용량인자가 최적 분리조건인 $0{\leq}logk'{\leq}1$ 범위를 만족시켰다. 용리거동에 관련된 인자들로는 용리액의 세기, 분포비$(D_c)$ 및 분리관의 온도변화에 따른 엔탈피(${\Delta}H^{\circ}$), 엔트로피(${\Delta}S^{\circ}$), 보정온도($\beta$)를 조사하여 분리 메카니즘을 규명하였다. 이성분 용매계에서 용리 세기 및 물의 부피분율과 용량인자(logk')와의 관계를 조사한 결과 이들간에는 직선성이 잘 성립되었으며, 부피비와 용량인자와의 관계에서도 비교적 직선성을 잘 나타내었다. 이러한 결과로부터 시료의 용리 메카니즘이 소용매성 효과에 기인하고 있음을 확인할 수 있었다. 또한 열역학적인 방법으로 용리거동을 조사하기 위하여, van't Hoff plot으로부터 엔탈피, 엔트로피를 구하였다. 엔탈피와 용량인자와의 상관관계를 조사한 결과 iron(III)porphyrin 착화합물과 정지상과의 상호작용은 온도변화에 과계없이 일정함을 알 수 있었고, 정지상과의 소용매성 결합 과정은 등평형 거동을 나타내었다.

• Preventive Nutrition and Food Science
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• 제7권1호
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• pp.12-17
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• 2002

Simultaneous determination of nine water-soluble vitamins contained in multi-nutrient tablets was carried out by reversed phase high-performance liquid chromatography (RP-HPLC) equipped with analytical $C_{18}$ column and UV (270 nm) detector. Those standard vitamins were successfully separated within 23 minutes by gradient elution with solvent A (0.5 M potassium phosphate monobasic) and solvent B (0.25 M potassium phosphate monobasic-methanol, 1:1). Calibration curves showed good linealities with correlation coefficients (> 0.92) in tested ranged respectively. The detection limits were considered to be 2.1 ng for ascorbic acids 60 ng for Vit B$_{6}$ 3 ng for p-aminobenzoic acid, 9 ng for niacinamide, 9 ng for thiamin, 5.0 ng for folic acid and 1.5 ng for riboflavin at 0.05 a.u.f.s. Solid phase extraction through Sep-Pak (C$_{18}$ ) cartridge was successfully applied for purification of water soluble vitamins in commercial multi-nutrient tablets.ts.