Signal amplification systems in immunoassays: implications for clinical diagnostics

Abstract

Biomarkers in physiological specimens serve as useful sensors for clinical diagnosis. Accurate detection of specific markers is crucial for the diagnosis of disease, monitoring drug therapy and patient screening. In vitro immunoassays are probably the most common, simple and relatively inexpensive serological tools used in clinical laboratories for the diagnosis and management of disease. Despite continued efforts to improve the performance of immunoassays in the past three decades, there is a need for highly sensitive assays that can detect the lowest levels of disease markers with greater accuracy. This review summarizes recent advances made towards increasing the sensitivity of immunoassays by amplifying detection signals, with implications for the development of highly sensitive diagnostic systems; it also discusses the principles of related methodologies.

Keywords::

• diagnostic tests
• immunoassays
• signal amplification

Disclaimer

The views presented in this article do not necessarily reflect those of the US FDA or the US Government.

I thank Neil Hardegen for flow cytometric analysis; Kenneth Yamada, Aridam Dhar, Krishnakumar Devadas and Indira Hewlett for critical review of the manuscript; Karen Smith for the up-to-date literature survey; and Faith Williams for excellent artwork.

Acknowledgement

I would like to dedicate this article to my guru Dr CM Gupta on his retirement as Director of Central Drug Research Institute, Lucknow, India after making several notable contributions in medicinal chemistry and basic membrane biology.