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Updated: Jul 17, 2026
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Simultaneous Detection of Different Antibody Classes in a Multiplexed Serological Test
Published on: July 14, 2023
Least detectable concentration and dynamic range of three immunoassay systems using the same antibody
Thomas R Glass1, Naoya Ohmura, Hiroshi Saiki
1Central Research Institute of the Electric Power Industry, Department of Bioscience, 1646 Abiko, Abiko City, Chiba, Japan.
Analytical Chemistry
|January 30, 2007
Summary
This study compared the performance of ELISA and two biosensor systems for estradiol detection. The kinetic exclusion biosensor showed the best performance, aligning with theoretical limits, unlike other systems.
Area of Science:
- Biotechnology and Biomedical Engineering
- Analytical Chemistry
- Immunotechnology
Background:
- Immunoassay systems are crucial for detecting analytes like estradiol.
- Comparing the performance of different immunoassay platforms is essential for selecting optimal detection methods.
- Understanding the least detectable concentration (LDC) and dynamic range (DR) is key to evaluating immunoassay sensitivity and utility.
Purpose of the Study:
- To compare the LDC and DR of three immunoassay systems: ELISA, surface plasmon resonance (SPR) biosensor, and kinetic exclusion (KE) biosensor.
- To evaluate immunoassay performance using four antibodies with varying affinities for estradiol.
- To assess the consistency of biosensor performance with antibody equilibrium dissociation constants (Kd).
Main Methods:
- Three immunoassay systems (ELISA, SPR, KE biosensor) were tested with four estradiol-specific antibodies of different affinities.
- Inhibition curves (response vs. estradiol concentration) were measured using blind samples analyzed by external experts and biosensor manufacturers.
- Equilibrium dissociation constants (Kd) were estimated by biosensor manufacturers for each antibody-system pair.
Main Results:
- The KE biosensor demonstrated LDC and DR consistent with Kd-limited detection.
- The SPR biosensor and ELISA exhibited LDC and DR exceeding expected Kd-limited performance.
- While each biosensor's results were internally consistent with its measured Kd, some contradictions were observed across platforms.
Conclusions:
- The KE biosensor offers superior performance, closely matching theoretical detection limits based on antibody affinity.
- ELISA and SPR biosensors may have detection limits influenced by factors beyond antibody-analyte binding kinetics.
- Utilizing multiple antibodies with varying affinities helps attribute performance differences to the immunoassay system rather than the analyte.
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