Two-photon Excitation Nanoprobe for DNases Activity Imaging Assay in Hepatic Ischemia Reperfusion Injury

Abstract We report the use of a novel two-photon excitation (TPE) nanoprobe in a DNase activity assay in vitro and ex vivo. This nanoprobe was mainly composed of a gold nanoparticle (AuNP) core as the cellular transporter and fluorescence quencher, and two-photon absorption dyes (TP dyes) that were inserted into the double-stranded DNA (dsDNA) as the reporter element. In the presence of DNases, the dsDNA immobilized onto the AuNP surface can be hydrolyzed into DNA fragments, thus resulting in the release of large amounts of TP dyes, the fluorescence recovery of the TP dyes and the activity measurement of DNases. This TPE nanoprobe has been successfully used to monitor the DNase activity in living cells and a hepatic ischemia reperfusion injury rat model.