%A G.P.S. Raghava %A A Joshi %A J N Agrewala %O Copyright of this article belongs to Elsevier Science. %J Journal of immunological methods %T Calculation of antibody and antigen concentrations from ELISA data using a graphical method. %X A graphical method for determining the concentration of either the antibody or the antigen from ELISA data is presented in the form of a GWBASIC program. In the program, ELISAEQ, optical densities (OD) obtained from a 96-well ELISA plate can be input either directly by interfacing a microplate reader to the computer or manually. The program uses standard sample data, and selects the semilogarithmic linear range. Over this range, a least-squares method is used to determine the concentrations of interest. In addition, a hyperbolic interpolation formula is derived over the entire range for estimating the antibody or antigen concentration of the unknown samples whose OD is beyond the linear range. %N 1-2 %P 263-4 %V 153 %D 1992 %I Elsevier Science %L open114