A new colorimetric strategy for monitoring caspase 3 activity by HRP-mimicking DNAzyme-peptide conjugates.

A new method for caspase 3 activity assay has been developed based on HRP-mimicking DNAzyme-peptide conjugates. The mechanism of detection was based on the specific cleavage of DEVD-peptides by active caspase 3 for recognition and the catalytic properties of HRP-mimicking DNAzymes for signal amplification. Under optimal conditions, the detection limit of caspase 3 was 0.89 nM. The proposed method was also successfully applied for the detection of caspase 3 in apoptosis cell lysates.