Acridinium Ester Chemiluminescence: Methyl Substitution on the Acridine Moiety

Methyl groups were introduced on the acridine moiety in chemiluminescent acridinium esters that have electron-withdrawing groups (trifluoromethyl, cyano, nitro, ethoxycarbonyl) at the 4-position on the phenyl ester. The introduction of methyl groups at the 2-, 2,7-, and 2,3,6,7-positions on the acridine moiety shifted the optimal pH that gave relatively strong chemiluminescence intensity from neutral conditions to alkaline conditions. 4-(Ethoxycarbonyl)phenyl 2,3,6,7,10-pentamethyl-10 lambda 4-acridine-9carboxylate, trifluoromethanesulfonate salt showed long-lasting chemiluminescence under alkaline conditions. Acridinium esters to determine hydrogen peroxide concentration at pH 7-10 were newly developed.

Automated summary

The introduction of methyl groups in acridinium esters can shift the optimal pH for relatively strong chemiluminescence from neutral to alkaline conditions. Certain compounds exhibit long-lasting chemiluminescence under alkaline conditions, which could be used for detecting hydrogen peroxide concentration.