Surface Plasmon Resonance Immunosensor for the Detection of Burkholderia pseudomallei

Environmental surveillance of the Gram-negative bacterium Burkholderia pseudomallei is important in order to define human populations at risk of acquiring the infection; hence, in this study, we developed a method for the detection of B. pseudomallei based on surface plasmon resonance (SPR) using 4-mercaptobenzoic acid (4-MBA) modified gold SPR chip by monitoring the interaction of rpGroEL antigen (rpGroEL Ag) with immobilized rabbit antibody (anti-rpGroEL rAb). Affinity constant (KD) and maximum binding capacity of analyte (Bmax) values for the interaction of rpGroEL Ag with the immobilized anti-rpGroEL rAb were calculated by using kinetic evaluation software and found to be 14.7 7 pM and 105.40 mo, respectively. In addition, thermodynamic parameters such as ∆G (Gibb’s free energy change), ∆H (change in the enthalpy), and ∆S (change in the entropy) were determined for the interaction between rpGroEL Ag and immobilized anti-rpGroEL rAb, and the values revealed that the interaction is spontaneous, exothermic, and driven by entropy.