Phototriggered Release of a Transmembrane Chloride Carrier from an o-Nitrobenzyl-Linked Procarrier.

While there have been many studies on synthetic chloride carriers and a recent application for apoptotic cell death, so far, the proposed huge potential of these systems in targeting cancer has not been realized due to their cytotoxicity to healthy cells. Herein, we describe the development of an indole-2-carboxamide receptor as an efficient membrane chloride carrier while the corresponding o-nitrobenzyl-linked derivative is a procarrier of the ion. Photoirradiation of the procarrier in liposomes results in release of the active carrier with up to 90 % transport efficiency. Such photorelease of the carrier also works within cancer cells, resulting in efficient cell killing. Such photocleavable procarriers have great potential as a photodynamic therapy to combat various types of cancers.