“…There have been numerous papers that have used chromatography and flow-injection analysis to perform simultaneous and sequential injection competitive binding immunoassays (De Alwis and Wilson, 1987;Arefev et al, 1990;Durst et al, 1991;Yap et al, 1991;Pollema et al, 1992a,b;Locascio-Brown et al, 1993;Mecklenburg et al, 1993;Palmer et al, 1993a,b;Pollema and Ruzicka, 1994;Rico et al, 1995;Johns et al, 1996;Martin-Esteban et al, 1996;Valencia-Gonzalez and Diaz-Garcia, 1996;Katmeh et al, 1997;Hage et al, 1993Hage et al, , 1999. However, there have been only a few studies that have examined the theoretical basis of these methods (Hage et al, 1993(Hage et al, , 1999.…”