A Decade of Development in Immunoassay Methodology

1990 ◽  
Vol 36 (8) ◽  
pp. 1408-1427 ◽  
Author(s):  
James P Gosling
Keyword(s):  
Monoclonal Antibodies ◽  
Liquid Phase ◽  
Analytical Methods ◽  
Clinical Laboratory ◽  
Solid Phase ◽  
Detection Limits ◽  
Assay System ◽  
Future Trends ◽  
Homogeneous Systems ◽  
Major Trend

Abstract Immunoassays are now very widely used in the clinical laboratory, either because no other type of assay system is feasible or because they are often the most effective and suitable of the possible analytical methods. The last decade has seen the development and refinement of many new immunoassay reagents and systems. The major trend has been away from liquid-phase assays involving radioisotopic labels, towards fast homogeneous or solid-phase assays capable of operation anywhere; and towards precise and reliable nonisotopic, automated or semi-automated laboratory assays, often with detection limits measured in pico- or attomoles. The use of monoclonal antibodies is now widespread, and the methodologies of labels and of solid-phase components are much more sophisticated. New assay formulations, novel homogeneous systems, immunosensors, free-analyte assays, the importance of thorough validation and of interfering substances, and future trends are discussed.

Monoclonal antibodies used in solid-phase and liquid-phase assays, as exemplified by progesterone assay.

1987 ◽  
Vol 33 (8) ◽  
pp. 1331-1337 ◽  
Author(s):  
W Schramm ◽  
T Yang ◽  
A R Midgley
Keyword(s):  
Monoclonal Antibodies ◽  
Liquid Phase ◽  
Solid Phase ◽  
Protein A ◽  
High Specificity ◽  
Binding Properties ◽  
Affinity Constants ◽  
Hybridoma Cell Lines ◽  
One Year ◽  
Better Than

Abstract Two immunoglobulins secreted by hybridoma cell lines have been systematically investigated to determine if they could be used in solid-phase assays to give results comparable with those obtained by conventional liquid-phase radioimmunoassay (RIA). The antibodies, BQ.1 and BQ.2, bind with high specificity to the steroid hormone progesterone. The affinity constants, Ka, to 125I-labeled progesterone derivatives are 1.1 X 10(11) L/mol and 9.1 X 10(9) L/mol, respectively. Progesterone inhibited the binding of radioiodinated derivatives (amides of tyramine, histamine, and tyrosine methylester with 11 alpha-progesterone hemisuccinate) equally well. For solid-phase assays, we immobilized antibody BQ.1 via Protein A to different polystyrene surfaces (about 30 pg per tube at 50% inhibition of radiolabeled tracer). Under these conditions, the performance of this antibody for the quantification of progesterone was equivalent to that obtained in RIA. For the immobilized antibody BQ.2, only 1/10 of the amount used for optimal results in RIA was required in solid-phase assays. Binding of either antibody to the antigen was undiminished after several freezing-thawing cycles. When immobilized on solid matrices, both antibodies retained up to 95% of their binding properties for one year. Thus high-affinity, high-specificity monoclonal antibodies can be obtained for haptens and, when suitably immobilized, can be used in solid-phase assays with results equal to or better than those obtained with liquid RIA.

Characterization of Four Monoclonal Antibodies to Factor VIII Coagulant Protein and Their Use in Immunopurification of Factor VIII

1986 ◽  
Vol 56 (03) ◽  
pp. 271-276 ◽  
Author(s):  
Marie-Pascale Croissant ◽  
Hendrik vande Pol ◽  
Helen H Lee ◽  
Jean-Pierre Allain
Keyword(s):  
Monoclonal Antibodies ◽  
Liquid Phase ◽  
Factor Viii ◽  
Ascitic Fluid ◽  
Specific Activity ◽  
Solid Phase ◽  
Functional Impact ◽  
Affinity Constants ◽  
Normal Plasma

SummaryFour monoclonal anti-VIII: C antibodies were obtained from the fusion of the splenocytes of one B alb/C mouse with a specific activity ranging from 2.3 to 45,000 U/mg when purified from ascitic fluid. Only one antibody was able to inhibit completely Factor VIII: C in normal plasma. The four antibodies could bind Factor VIII: CAg in plasma and commercial concentrate both in liquid and solid phase, and were suitable for immunopurification of Factor VIII :C.Three antibodies competed with polyclonal anti-VIII: CAg Fab′ in a liquid phase IRMA, and all of them were able to displace their own binding to Factor VIII: CAg. Competition studies between monoclonal antibodies for the binding to Factor VIII: CAg were performed and showed the recognition of different epitopes and various functional impact. These studies indicate that at least one antibody, with the lowest anti-VIII:C titer clearly recognizes a different epitope of VIII: C than those recognized by the others. Affinity constants ranged from 109 to 1010 l/mole.

Analysis of the Temporal Compressibility of Breast Tumour Marker Assays: Development of a “Near Patient” Assay

1995 ◽  
Vol 10 (4) ◽  
pp. 200-205 ◽  
Author(s):  
A. Murray ◽  
J. F. R. Robertson ◽  
M. R. Price
Keyword(s):  
Breast Cancer ◽  
Monoclonal Antibodies ◽  
Liquid Phase ◽  
Solid Phase ◽  
Breast Tumour ◽  
Tumour Marker ◽  
Binding Kinetics ◽  
Immunoradiometric Assay ◽  
Assay Performance ◽  
Kinetics Of

The aim of this study was to investigate whether immunoassays for circulating MUC1 antigen in breast cancer could be compressed in time so that serum level results would be made available during the time of the patient's visit to clinic. Two assays were used: - The EMCA (Euro DPC) is a liquid phase immunoassay and the ELSA CA15-3 (CIS) is a double determinant solid phase immunoradiometric assay. The effects of shortened incubation times were investigated by assaying standards and unknown samples and comparing the results with those using the standard kit protocols. The binding kinetics of the monoclonal antibodies employed in the assays were analysed separately. We conclude that the EMCA assay can be shortened to 35 min and we have attributed this to the fast binding kinetics inherent in a liquid phase assay. This shortened assay may produce the basis for a useful “near patient” assay. By comparison, the solid phase ELSA CA15-3 assay cannot be compressed without loss in assay performance.

Identification of hepatitis a virus in cell cultures by solid phase immune electron microscopy

1986 ◽  
Vol 44 ◽  
pp. 238-239
Author(s):  
C.D. Humphrey ◽  
T.L. Cromeans ◽  
E.H. Cook ◽  
D.W. Bradley
Keyword(s):  
Electron Microscopy ◽  
Liquid Phase ◽  
Cell Cultures ◽  
Rapid Detection ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Solid Phase ◽  
Immune Electron Microscopy ◽  
Detection And Identification

There is a variety of methods available for the rapid detection and identification of viruses by electron microscopy as described in several reviews. The predominant techniques are classified as direct electron microscopy (DEM), immune electron microscopy (IEM), liquid phase immune electron microscopy (LPIEM) and solid phase immune electron microscopy (SPIEM). Each technique has inherent strengths and weaknesses. However, in recent years, the most progress for identifying viruses has been realized by the utilization of SPIEM.

Characterization of Monoclonal Anti-human Factor VII Antibody (B101/B1) that Recognized Three-dimensional Structures near Arg at Position 79 in the First EGF-like Domain

1998 ◽  
Vol 79 (01) ◽  
pp. 104-109 ◽  
Author(s):  
Osamu Takamiya
Keyword(s):  
Monoclonal Antibodies ◽  
Tissue Factor ◽  
Human Factor ◽  
Solid Phase ◽  
Three Dimensional ◽  
Coagulation Factors ◽  
Factor Vii ◽  
Dimensional Structure ◽  
Epidermal Growth

SummaryMurine monoclonal antibodies (designated hVII-B101/B1, hVIIDC2/D4 and hVII-DC6/3D8) directed against human factor VII (FVII) were prepared and characterized, with more extensive characterization of hVII-B101/B1 that did not bind reduced FVIIa. The immunoglobulin of the three monoclonal antibodies consisted of IgG1. These antibodies did not inhibit procoagulant activities of other vitamin K-dependent coagulation factors except FVII and did not cross-react with proteins in the immunoblotting test. hVII-DC2/D4 recognized the light chain after reduction of FVIIa with 2-mercaptoethanol, and hVIIDC6/3D8 the heavy chain. hVII-B101/B1 bound FVII without Ca2+, and possessed stronger affinity for FVII in the presence of Ca2+. The Kd for hVII-B101/B1 to FVII was 1.75 x 10–10 M in the presence of 5 mM CaCl2. The antibody inhibited the binding of FVII to tissue factor in the presence of Ca2+. hVII-B101/B1 also inhibited the activation of FX by the complex of FVIIa and tissue factor in the presence of Ca2+. Furthermore, immunoblotting revealed that hVII-B101/B1 reacted with non-reduced γ-carboxyglutaminic acid (Gla)-domainless-FVII and/or FVIIa. hVII-B101/B1 showed a similar pattern to that of non-reduced proteolytic fragments of FVII by trypsin with hVII-DC2/D4 on immunoblotting test. hVII-B101/B1 reacted differently with the FVII from the dysfunctional FVII variant, FVII Shinjo, which has a substitution of Gln for Arg at residue 79 in the first epidermal growth factor (1st EGF)-like domain (Takamiya O, et al. Haemosta 25, 89-97,1995) compared with normal FVII, when used as a solid phase-antibody for ELISA by the sandwich method. hVII-B101/B1 did not react with a series of short peptide sequences near position 79 in the first EGF-like domain on the solid-phase support for epitope scanning. These results suggested that the specific epitope of the antibody, hVII-B101/B1, was located in the three-dimensional structure near position 79 in the first EGF-like domain of human FVII.

SYNTHESIS OF HYDROGEN IN ACOUSTOPLASMA DISCHARGE IN A LIQUID-PHASE STREAM

2019 ◽  
pp. 42-48 ◽  
Author(s):  
N. A. Bulychev
Keyword(s):  
Liquid Phase ◽  
Organic Compounds ◽  
Electrode Materials ◽  
Solid Phase ◽  
Plasma Discharge ◽  
Raw Material ◽  
Two Phase ◽  
Reduced Pressure ◽  
External Power Source ◽  
Phase Medium

In this paper, the plasma discharge in a high-pressure fluid stream in order to produce gaseous hydrogen was studied. Methods and equipment have been developed for the excitation of a plasma discharge in a stream of liquid medium. The fluid flow under excessive pressure is directed to a hydrodynamic emitter located at the reactor inlet where a supersonic two-phase vapor-liquid flow under reduced pressure is formed in the liquid due to the pressure drop and decrease in the flow enthalpy. Electrodes are located in the reactor where an electric field is created using an external power source (the strength of the field exceeds the breakdown threshold of this two-phase medium) leading to theinitiation of a low-temperature glow quasi-stationary plasma discharge.A theoretical estimation of the parameters of this type of discharge has been carried out. It is shown that the lowtemperature plasma initiated under the flow conditions of a liquid-phase medium in the discharge gap between the electrodes can effectively decompose the hydrogen-containing molecules of organic compounds in a liquid with the formation of gaseous products where the content of hydrogen is more than 90%. In the process simulation, theoretical calculations of the voltage and discharge current were also made which are in good agreement with the experimental data. The reaction unit used in the experiments was of a volume of 50 ml and reaction capacity appeared to be about 1.5 liters of hydrogen per minute when using a mixture of oxygen-containing organic compounds as a raw material. During their decomposition in plasma, solid-phase products are also formed in insignificant amounts: carbon nanoparticles and oxide nanoparticles of discharge electrode materials.

Analytical Methods for Solid Phase Peptide Synthesis

2004 ◽  
Vol 8 (4) ◽  
pp. 291-301 ◽  
Author(s):  
Giuseppina Sabatino ◽  
Mario Chelli ◽  
Alberto Brandi ◽  
Anna Papini
Keyword(s):  
Peptide Synthesis ◽  
Analytical Methods ◽  
Solid Phase ◽  
Solid Phase Peptide Synthesis

A simple assay system incorporating monoclonal antibodies for the detection of potato virus T

1993 ◽  
Vol 36 (2) ◽  
pp. 83-88 ◽  
Author(s):  
Mairi L. Vernon-Shirley ◽  
Robert Burns ◽  
Edna L. George ◽  
Margaret E. Hoadley
Keyword(s):  
Monoclonal Antibodies ◽  
Potato Virus ◽  
Assay System

scholarly journals A Novel Quinoxaline-Rhodamine Conjugate for a Simple and Efficient Detection of Hydrogen Sulphate Ion

Compounds ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 29-40
Author(s):  
Sutapa Sahu ◽  
Yeasin Sikdar ◽  
Riya Bag ◽  
Dilip K. Maiti ◽  
José P. Cerón-Carrasco ◽  
...  
Keyword(s):  
Solid Phase ◽  
Detection Limits ◽  
Hydrogen Sulfate ◽  
Absorption And Emission ◽  
Conjugate System ◽  
Colorimetric Chemosensor ◽  
Simple Strategy ◽  
Efficient Detection ◽  
Hydrogen Sulphate

This work presents the development of a quinoxaline and rhodamine conjugate system that acts as a colorimetric chemosensor for hydrogen sulfate (HSO4−) ions in methanol media. This sensor has been characterized both theoretically and experimentally. The detection limits for HSO4− are small as 0.71 µM and 3.8 µM for the absorption and emission experiments, respectively. The effectiveness of the probe in recognizing HSO4− both in gel and solid phase is evaluated as well. Thus, this works presents a simple strategy to detect the environmental HSO4− pollutant event at tiny concentrations.

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