Using acridinium ester as the sonochemiluminescent probe for labeling of protein.

A new sonogenerated chemiluminescence (SCL) system has been developed to investigate the SCL behavior of acidinium ester (AE). The optimum parameters for this SCL system have also been investigated in detail. Under the optimum conditions, a typical SCL signal could be obtained in a mixture of DMF and alkaline water solutions with volume ratio of 3:2. According to electrospray ionization mass spectrometry and sonochemiluminescence emission spectra, SCL emission could be ascribed to the formation of N-methylacridone with a different mechanism from that in both the chemiluminescence and electrochemiluminescence reaction of acridinium ester. The acridinium ester has been used as a SCL probe for labeling of anti-human insulin guinea pig polyclonal antibody, and it was found that the concentration of AE-conjugated antibody was linear with the SCL intensity in the range of 0.15-0.75 ppb with a linear correlation coefficient of 0.9980.