Computer screen photo-assisted detection of complementary DNA strands using a luminescent zwitterionic polythiophene derivative

The computer screen photo-assisted technique (CSPT), a practical method for the evaluation of assays using computer screens as light sources and web cameras as detectors, has been used to detect the attachment of complementary DNA strands (20-mer, 5′-CAT GAT TGA ACC ATC CAC CA-3′) to a complex of single DNA strands and a polythiophene derivative (poly(3-[(S)-5-amino-5-carboxyl-3-oxapentyl]-2,5-thiophenylene hydrochloride (POWT)). The complex is a highly sequence specific indicator, based on non-covalent coupling of DNA to a water-soluble, zwitterionic, electroactive and photoactive polymer able to produce a combined absorption-emission signal readable by CSPT. served CSPT signal retains key spectral features of the complex spectrum, distinguishing the DNA attachment, as well as other stimuli, such as pH regulation at concentrations of 30 μM POWT and 15 μM DNA. A CSPT time resolved (linked to temperatures between 8 and 18 °C) approach is demonstrated as a complementary source of discrimination and for testing the robustness of the achieved classification.