• Bulletin of the Korean Chemical Society
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• 제18권1호
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• pp.44-50
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• 1997

A method of dual-signal generation from two different enzymes was developed and utilized to simultaneously perform dual immunoassays in a single microwell. Two enzymes selected as tracers were horseradish peroxidase (HRP) and β-galactosidase (GAL). 3, 3', 5, 5'-Tetramethylbenzidine (TMB) and chlorophenolred-β-galactopyranoside (CPRG) as chromogenic substrates for the respective enzyme were used. Although the two enzymes showed their maximum activities at distinct pH conditions (pH 5.1 for HRP and 7.5 for GAL), the enzyme reactions were able to be concurrently carried out at pH 5.75 in a dual-substrate solution without signal loss. This performance was achieved by increasing TMB concentration two-fold, introducing potassium salt as activator of GAL reaction, and extending total reaction time 50%. The signal generation method was then used for dual-enzyme immunoassays to detect antibodies with co-immobilized Hepatitis C virus antigens (core and NS5) and a Hepatitis B virus antigen (PreS(2)) in a microwell. Dose-response curves of the assays revealed cooperativity between different antigen-antibody complex formation, which suggested that dual immunoassays can only be used for qualitative screening tests unless the antigens immobilized were spatially separated.

• 약학회지
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• 제47권5호
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• pp.266-270
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• 2003

We evaluated four commercially available methamphetamine immunoassays for their relative cross-reactivities of amphetamine analogues in human urine: Abbott TDx, Vitalab Selectra and on-site test kits (Accusign MET, SD bioline MET). High cross-reactivities were shown at designer's drugs such as methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA) and methylenedioxyethylamphetamine (MDEA) in all of the tested immunoassays. Methoxyphenamine, fenfluramine and phentermine were positive in TDx and Selectra, but were not positive in on-site test kits. Pseudoephedrine, norpseudoephedrine, ephedrine, norephedrine, MDMA, MDA, fenfluramine and phentermine were detected by gas chromatography/mass spectrometry(GC/MS) in false positive urines. Since the overall specificity of any of the devices was not 100％, we found it is important to confirm any positive screening test result, so we developed simultaneous determination of amphetamine analogues in urines. After alkalinization of the urine samples with 6-N NaOH, the analytes were extracted using ethyl acetate, derivatized with pentafluoropropyl anhydride (PFPA) prior at GC/MS analysis.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.297.1-297.1
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• 2002

Immunoassays are frequently used for an screening method to detect the presence of drugs in Urine. The main advantages of the method are well known -- simplicity of handling samples. rapidity. sensitivity. and specificity of analysis. However. it is also known that immunoassays exhibit cross-reactivity to related drugs and there are only limited specific immunoassays on the market. This study reports on the ability of TDx to detect urine samples obtained from suspects of taking over-the-counter medications and illegal drugs containing ATS. designer drugs. (omitted)

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 1998년도 제3차 심포지움
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• pp.20-24
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• 1998

• 대한생식의학회:학술대회논문집
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• 대한불임학회 1996년도 춘계 학술대회
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• pp.3-11
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• 1996

• 한국환경보건학회지
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• 제34권6호
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• pp.433-438
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• 2008

Much of the increase in agricultural productivity over the past half century has been due to the control of the pests with synthetic pesticides. The use of these pesticides has caused environmental problems and public health concern. The guidelines of maximum residue levels of pesticides in agricultural products has been well documented but more careful monitoring of their residues is required. Pyrethorid class pesticides are dominant in modern agricultural industry but public health concerns have been recently considered. The major route of pesticide exposure is the diet and with improved surveillance of pyrethorid residues in agricultural products their exposure should be controlled and minimized. In suitable products with reduced matrix effects such as agricultural products, aqueous samples, fruits and vegetables the use of immunoassays for pyrethorid residue monitoring could satisfy this requirement. Immunoassays have several advantages, namely they are highly sensitive, selective and cost-effective and enable large-scale sample handling and analysis in the laboratory.

• Animal cells and systems
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• 제7권1호
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• pp.89-92
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• 2003

Immunoassays have become indispensable tools and achieved great importance in scientific and medical research. However, typical immunoassays are time-consuming and use complex, multi-step procedures. In this study, we introduce a new immunoassay system for the quantification of several analytes at a time without any washing steps. It is comprised of a detector solution with fluorescence-labeled antibodies and a test strip with immobilized capture antibodies. Using a micro-array scanner, the antigen-antibody complex was quantitatively determined by measuring the intensities of fluorescence on the capture lines or dots of nitrocellulose membrane. This method demonstrated its rapid quantitative determination of analytes without many processing steps as well as specific identification of multiple analytes in biological specimens.

• The Plant Pathology Journal
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• 제26권2호
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• pp.207-214
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• 2010

• Bulletin of the Korean Chemical Society
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• 제22권4호
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• pp.417-420
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• 2001

• 한국발생생물학회지:발생과생식
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• 제9권2호
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• pp.65-83
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• 2005

면역측정법의 주요 발전 단계를 3가지로 구분한다. 즉 첫 발전 단계(제 1세대)는 방사성 호르몬(방사선 추적자, radiolabeled analyte marker)을 이용한 길항적 측정방법의 개발과 보급이다. 두 번째(제 2세대)는 단가 항체(monoclonal antibody, McAb)를 추적자로 만들고, 비방사성 표지자를 이용하여 비경쟁적 초감도의 측정방법이 면역진단 분야에 적용되는 단계이다. 세 번째(제 3세대)의 발전은 최소량화, 칩을 이용하는(chip-based) microarray의 방법을 응용하여, 한 시료에서 여러 가지 생리활성물질 즉 호르몬의 동태를 파악하는 초감도 다변량분석법(simultaneous ultrasensitive measurement)이 개발되고 보급되는 단계라 할 수 있다. 제 1세대의 방사면역측정법(radioimmunoassay, RIA)을 거쳐 제 2세대 비방사면역측정법(non-isotopic immunoassay methods, NIA)이 모두 장 단점이 비교되고, 각각의 특수성을 가진 측정법이 정립되고, 시장에서의 우열이 정리되고 있는 시점이다. 이미 제 3세대(Chip/microarray-based multianalyte ligand assays)가 매우 빠르게 개발되고 있어 새로운 전환기를 맞고 있다고 판단된다. 그러나 본 종설에서는 일차로 제 2세대를 정리하고, 이어 새로운 전환점의 측정법을 소개하고자 한다.