Immunological Techniques in Microbiology: ELISA, Agglutination, Rapid Tests, and Serological Assays

https://doi.org/10.66715/cerebral-link/2026.v4.C13.143155 | Cerebral Link | Publish by Cerebral Publication Private Limited | 2026 | Volume 4 | Page 143-155 | ISBN: 978-81-689463-6-1| Book Title: - Text-book of Practical Microbiology | Chapter-13: Immunological Techniques in Microbiology: ELISA, Agglutination, Rapid Tests, and Serological Assays

Dr Mahak Jain, Associate Professor, Department of Microbiology, Heritage Institute of Medical Sciences, Varanasi, Uttar Pradesh.

Immunological Techniques in Microbiology: ELISA, Agglutination, Rapid Tests, and Serologic.

Download • 1.34MB

Abstract

Immunological techniques are fundamental components of modern microbiology, providing rapid, sensitive, and specific approaches for the detection of microbial antigens, antibodies, and host immune responses associated with infectious diseases. This chapter presents the principles, procedures, interpretation, and applications of major immunological methods, including enzyme-linked immunosorbent assay (ELISA), agglutination tests, rapid diagnostic tests, and conventional serological assays. ELISA techniques are discussed with emphasis on direct, indirect, sandwich, and competitive formats used for qualitative and quantitative detection of infectious disease markers. Agglutination methods, including slide, tube, latex, and hemagglutination assays, are described in relation to microbial identification and antibody detection. Rapid immunochromatographic tests are highlighted for their importance in point-of-care diagnosis, particularly where immediate clinical decision-making is required. The chapter also covers serological approaches such as precipitation, complement-based assays, immunofluorescence, and antibody titre determination. Particular attention is given to sensitivity, specificity, cross-reactivity, quality control, specimen handling, interpretation of results, and potential causes of false-positive and false-negative findings. Recent developments in automated immunoassays, multiplex platforms, and advanced biosensor-based diagnostics are also considered. Collectively, these techniques remain essential for infectious disease diagnosis, epidemiological surveillance, screening, research, and monitoring of immune responses.