Temperature modulated excitation and phase sensitive detection to selectively image DNA sequences

Temperature oscillations allow one to modulate the concentration of reagents and products with given amplitude and phase shift, both parameters depending on the dynamics of the chemical system under study. We here rely on thermal excitation in a microdevice, associated with fluorescence video microscopy as well as image filtering protocols, to selectively enhance the signal issued from a labeled probe that hybridizes with a targeted oligonucleotide. Furthermore, by simply tuning the stimulation parameters, focus can be put either on the perfect match sequence or on some other one that bears a point mutation.