Filterless fluorescent DNA sensing in capillary tube PCR

Abstract

Abstract The method of applying programmed tilt displacements on Polymerase Chain Reaction (PCR) reactants held in capillary tubes that are displaced to and from closely adjacent holding regions kept at different constant temperatures overcomes many of the issues encountered with other approaches. Investigations here found laser diode line generators to provide sufficient excitation light levels but not electroluminescent (EL) wires for fluorescent emission detection. When optical fiber sensing was used, the levels of excited light from scattering far exceeded the fluorescent emission levels from the reagent. Camera recording however enabled filterless detection of the fluorescent emission as the excitation light levels from the scattering was low enough and fluorescent imaging was facilitated by the point spread function (PSF) axial length conditions being met. The capacity for quantitative PCR was also illustrated using an architecture comprising a heated glass block.