Photo-induced eradication of human colorectal adenocarcinoma HT-29 cells by carbon monoxide (CO) delivery from a Mn-based green luminescent photoCORM

Abstract

Exogenous CO delivery to cellular targets for salutary purposes can be readily achieved with photoactive metal carbonyl complexes (photoCORMs). Mn(I)-based photoCORMs are often favored for their ability to release CO upon triggering with visible light (suitable for phototherapy of cancer). To date, the reported Mn(I)-based photoCORMs are all non-luminescent and hence the entry of these CO donors cannot be tracked within the targeted sites. A new luminescent Mn(I) photoCORM namely [Mn(CO)3(phen)(Pipdansyl)](CF3SO3) (3) has been reported. Synthetic strategy to isolate photoCORM 3 and its previous analogue [Mn(CO)3(phen)(Imdansyl)](CF3SO3) (2) has been highlighted to establish protocols for the future isolation of luminescent Mn(I)-based photoCORMs that could be employed as trackable photoCORMs for CO delivery. The entrance of 3 into human colorectal adenocarcinoma HT-29 cells has been visualized by confocal microscopic studies. Eradication of the cancer cells by CO delivery from 3 under visible light illumination has also been demonstrated.