CENTA is a colorimetric cephalosporin substrate for β-lactamases.^1,2Upon hydrolysis by β-lacatamases, CENTA turns from light yellow to chrome yellow, which can be quantified by colorimetric detection at 405 nm as a measure of β-lactamase activity.

1.Jones, R.N., Wilson, H.W., Novick Jr., W.J., et al.In vitro evaluation of CENTA, a new beta-lactamase-susceptible chromogenic cephalosporin reagentJ. Clin. Microbiol.15(5)954-958(1982) 2.Bebrone, C., Moali, C., Rival, S., et al.CENTA as a chromogenic substrate for studying beta-lactamasesAntimicrob. Agents Chemother.45(6)1868-1871(2001)