Inner salt-shaped small molecular photosensitizer with extremely enhanced two-photon absorption for mitochondrial-targeted photodynamic therapy
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Making a light-capturing drug molecule more like salt dramatically improved its ability to kill cancer cells, a China-Singapore team have shown.
Photodynamic therapy is a cancer therapy in which beams of light are focussed on tumour cells inside the body. Light-sensitive drug molecules given to the patient before the treatment accumulate in the tumour cells and capture the light, the drug then generates reactive oxygen radicals that kill the diseased cell.
‘Two-photon’ photodynamic therapy is a precisely focussed version of the treatment that limits damage to surrounding tissue. The team, which included Nanjing Tech University researchers, helped develop a molecule called DBA that undergoes two-photon capture. DBA was found to capture the light with two orders of magnitude higher efficiency than previous drugs. The key innovation was to give the molecule a salt-like structure which boosted its performance in the polar conditions found in the body. DBA then rapidly and efficiently killed cancer cells when targeted by light.
- Chemical Communications 53, 1680–1683 (2017). doi: 10.1039/c6cc09473b