• Archives of Pharmacal Research
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• 제17권4호
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• pp.244-248
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• 1994

A stereoselective and sensitive high performance liquid chromatography using fluoresecence deterctor was examined for the determination of R(-) and S(+)-salbutamol in human plasma. Solid phase extraction method using silica as sorbent was used to extract salbutamol racemates from the plasma matrices. After fractionation and freeze-drying of the eluates containing salbutamol racemates, they were separated and quantified on a chirla stationary column. The detection limit of each enantiomer was 2 ng/ml in human plasma (S/N=3).

• 분석과학
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• 제21권4호
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• pp.259-271
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• 2008

혈액 내에 축적되어 있는 유기염소계 농약을 분석하기 위한 방법으로 기존에는 액체-액체 추출법과 고체상 추출법을 많이 사용하였으나 정제 및 많은 양의 시료 처리에 한계가 있다. 이를 극복하기 위한 방법으로 시료양이 적으며 간편한 고체상미량추출법을 사용하여 혈액 중 18종의 유기염소계 농약의 최적 추출법을 연구하였다. 흡착조건(fiber type, 흡착시간, 흡착온도, 염석효과)과 탈착조건(탈착시간, 탈착온도) 등 최적의 추출을 위해 여러 가지의 실험조건 등을 검토한 결과, fiber는 polyacrylate $85{\mu}m$, 흡착시간은 50분, 흡착온도는 $80^{\circ}C$, 염석효과는 NaCl 0.1 g, 탈착시간은 5분, 탈착온도는 $280^{\circ}C$에서 최적임을 확인하였다. 정확도, 정밀도 및 검출한계에 대한 타당성을 최적 실험조건에서 조사한 결과, 검출한계는 0.05~0.20 ng/mL, 정밀도는 5.59~13.39%, 정확도는 -0.5%~24.5%의 범위인 것으로 확인되었다.

• 한국가축번식학회지
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• 제9권2호
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• pp.133-139
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• 1985

An immunoassay may be defined as an analytical procedure involving the competitive reaction between a limiting concentration of specific antibody and two populations of antigen, one of which is labelled or immobillized. The advent of immunoassay has revolutionised our knowledge of reproductive physiology and the practice of veterinary and clinical medicine. Radioimmunoassay (RIA) was the first of these methods to be developed, which meausred the analyte with good sensitivity, accuracy and precision (1,2). The essential components of RIA are:-(i) a limited concentration of antibodies, (ii) a reference preparation, and (iii) an antigen labelled with a radioisotope (usually tritium or iodine-125). Most procedures invelove isolating the antibody-bound fraction and measuring the amount of labelled antigen. Good facilities are available for scintilltion counting, data reduction nd statistical analysis. RIA is undergoing refinement through:-(i) the introduction of new techniques to separate the antibody-bound and free fractions which minimize the misclassification of labelled antigen into these compartments, and the amount of non-specfic binding. (3), (ii) the development of non-extration for the measurement of haptens (4), (iii) the determination of a, pp.rent free (i.e. non-protein bound) analytes (5), and (iv) the use of monoclonal antibodies(6). In 1968, Miles and Hales introduced in important new type of immunoassay which they termed immunora-diometric assay (IRMA) based on t도 use of isotopically labelled specific antibodies(7) in a move from limited to excess reagent systems. The concept of two-site IRMAs (with a capture antibody on a solid-phase, and a second labelled antibody to a different antigenic determinant of the analyte) has enabled the development of more sensitive and less-time consuming methods for the measurement of protein hormones ovar wide concentration of analyte (8). The increasing use of isotopic methos for diverse a, pp.ications has exposed several problems. For example, the radioactive half-life and radiolysis of the labelled reagent limits assay sensitivity and imposes a time limit on the usefulness of a kit. In addition, the potential health hazards associated with the use and disposal of radioactive cmpounds and the solvents and photofluors necessary for liquid scientillation counting are incompatable with the development of extra-laboratory tests. To date, the most practical alternative labels to radioisotopes, for the measurement of analytes in a concentration > 1 ng/ml, are erythrocytes, polystyrene particiles, gold sols, dyes and enzymes or cofactors with a visual or colorimetric end-point(9). Increased sensitivity to<1 pg/ml may be obtained with fluorescent and chemiluminescent labels, or enzymes with a fluorometric, chemiluminometric or bioluminometric end-point. The sensitivity of any immunoassay or immunometric assay depends on the affinity of the antibody-antigen reaction, the specific activity of the label, the precision with which the reagents are manipulated and the nonspecific background signal (10). The sensitivity of a limited reagent system for the measurement of haptens or proteins is mainly dependent upon the affinity of the antibodies and the smalleest amount of reagent that may be manipulated. Consequently, it is difficult in practice to improve on the sensitivity obtained with iodine-125 as the label. Conversely, with excess reagent systems for the measurement of proteins it is theoretically possible to increase assay sensitivity at least 1000 fold with alternative luminescent labels. To date, a 10-fold improvement has been achieved, and attempts are being made to reduce the influence of other variables on the specific signal from the immunoreaction.