Automated and data-reliable determination of tetanus toxoid antibodies in human serum using surface plasmon resonance

In low- and middle-income countries, tetanus continues to be a major public health concern. The best protection against tetanus is to be vaccinated and receive boosters on time throughout life to maintain adequate immunity. The concentration level of protective antibodies in the serum is the primary indicator of whether it is necessary to strengthen immunization. Here, we report a novel serum concentration assay for tetanus antibodies based on surface plasmonic resonance (SPR). Because of avoiding the long incubation / separation / washing / detection steps of the methods proposed so far and reducing variability, the developed method has the obvious advantages of directly and accurately measuring serum antibodies in minutes. In addition, the proposed method has wide linear range of 0.001 IU/mL-0.1 IU/mL, lower quantitation limit of 0.001 IU/mL, and exhibits excellent precision and overall accuracy. The method is easily automated for high throughput operation, providing a useful analytical tool for human serological investigation of tetanus antibody to regulatory agencies.