Pathogen detection, immobilization antibodies

A special nonspecific sensor response might be due to the cross-reactivity of immobilized antibodies. Besides the analyte, an antibody can bind also other entities bearing a similar antigenic epitope, e.g. the detection of some pathogenic bacteria can be interfered by the binding of non-pathogenic bacteria with the same surface antigen. 

Figure 9.22 Multiplexed detection of pathogens using NC antibody conjugates and MWCNT-PAH/SPE. Step I antibody immobilization Step 2 immunocapture Step 3 NC-an-tibody conjugates immunobinding Step 4 dissolution of metal ions from NC and Step 5 SWSV analysis (Reproduced from [143], with permission from Elsevier)...

Immobilized lysate antigen of E. coli 0157 H7 at different concentrations was assayed and the low detection limit was 3 gg/mL. The assay also demonstrated very good specificity different microbial lysate antigens were immobilized, including E. coli and H. pylori, and the primary and secondary antibodies were mixtures of different species. The assay time is only 25 min (the conventional lab based assay requires over 3 h) the sample consumed was less than 12 pL. While still an un-optimized chip, this lA chip shows a great potential in detecting multiple pathogen efficiently. 

Design and Synthesis of Dendritic Tethers for the Immobilization of Antibodies for the Detection of Class A Bioterror Pathogens, Chapter 10... 

This method can also be applied for the detection of microorganisms. The immobilization of the antibody anti-Candida enables the measurement of the pathogenic microbe Candida albicans at concentrations between 10 to 5 x 10 cells/cm [254],... 

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