Photoelectrochemistry with controlled DNA-cross-linked CdS nanoparticle arrays

Photochemical detection of a nucleic acid was achieved by means of a DNA-cross-linked CdS nanoparticle array attached to an electrode (see schematic diagram). The array was constructed from the target DNA (blue) and SdS nanoparticles bearing oligonucleotides complementary to its 3′-(green) and 5′-ends (red). The photocurrent generated on irradiation of the array increases with increasing concentration of the target.