Anthrax, caused by Bacillus anthracis is an important disease of biowarfare and public health importance. It is imperative to develop a simple system which can detect and differentiate B. anthracis from other closely related species. The surface array protein (Sap), which is secreted during the early growth phase of bacteria can be an important biomarker for detection of B. anthracis. In the present study, we have developed a rapid flow through membrane ELISA for detection of B. anthracis. Polyclonal antibodies were used to develop a sandwich plate ELISA, which could detect 3.9 ng/ml of recombinant Sap. B. anthracis bacteria grown in culture broth could be detected after 5 h of growth. Finally, a rapid flow through membrane ELISA was developed which can be accomplished just within 2 minutes, instead of 3-4 h as required in sandwich plate ELISA. The results established that the developed flow through membrane ELISA may be used for detection of B. anthracis. The proposed method is rapid, safe and user friendly for detection of B. anthracis culture. 2. Walsh, J.J.; Pesik, N.; Quinn, C.P.; urdaneta, V.;Dykewicz, C.A.; Boyer, A.E., et al. A case of naturally acquired inhalation anthrax: clinical care and analyses of anti-protective antigen immunoglobulin G and lethal factor. clin. Infect. Dis., 2007, 44(7), 968-971. 7. Jimenez, G.; urdiain, M.; Cifuentes, A.; Lopez-Lopez, A.; Blanch, A.R.; Tamames, J., et al. Description of Bacillus toyonensis sp. nov., a novel species of the Bacillus cereus group, and pairwise genome comparisons of the species of the group by means of ANI calculations. syst. appl.