A system for measuring analytical reactions comprising: an optode array chip comprising: a two dimensional array of optode elements, each optode element comprising: a nanoscale aperture within an aperture layer, the aperture forming a fluid receiving nanoscale well for receiving a fluid including fluorescent species; above the aperture layer, a fluidic layer in fluidic contact with the nanoscale well; below the aperture layer, a waveguide layer that provides illumination to the nanoscale well, the waveguide layer comprising an array of channel waveguides, each channel waveguide extending across a plurality of optode elements; below the waveguide layer, a transmission layer that transmits light emitted from the fluorescent species in the nanoscale well to a detector layer; and below the transmission layer, the detector layer comprising a detector which receives and detects the emitted light from the nanoscale well and transmitted through the transmission layer; a fluidics delivery system for delivering fluid to the optode array elements; an illumination system that delivers illumination to waveguides of the optode array elements; and a socket (51, 57) for holding the optode array chip; wherein the socket (51, 57) has electrical contacts that mate with electrical contacts on the chip, whereby electrical signals from the detector relating to detected emitted light are transmitted off of the chip through the electrical contacts. an optode array chip comprising: a two dimensional array of optode elements, each optode element comprising: a nanoscale aperture within an aperture layer, the aperture forming a fluid receiving nanoscale well for receiving a fluid including fluorescent species; above the aperture layer, a fluidic layer in fluidic contact with the nanoscale well; below the aperture layer, a waveguide layer that provides illumination to the nanoscale well, the waveguide layer comprising an array of channel waveguides, each channel waveguide extending across a plurality of optode elements; below the waveguide layer, a transmission layer that transmits light emitted from the fluorescent species in the nanoscale well to a detector layer; and below the transmission layer, the detector layer comprising a detector which receives and detects the emitted light from the nanoscale well and transmitted through the transmission layer; a nanoscale aperture within an aperture layer, the aperture forming a fluid receiving nanoscale well for receiving a fluid including fluorescent species; above the aperture layer, a fluidic layer in fluidic contact with the nanoscale well; below the aperture layer, a waveguide layer that provides illumination to the nanoscale well, the waveguide layer comprising an array of channel waveguides, each channel waveguide extending across a plurality of optode elements; below the waveguide layer, a transmission layer that transmits light emitted from the fluorescent species in the nanoscale well to a detector layer; and below the transmission layer, the detector layer comprising a detector which receives and detects the emitted light from the nanoscale well and transmitted through the transmission layer; a fluidics delivery system for delivering fluid to the optode array elements; an illumination system that delivers illumination to waveguides of the optode array elements; and a socket (51, 57) for holding the optode array chip; wherein the socket (51, 57) has electrical contacts that mate with electrical contacts on the chip, whereby electrical signals from the detector relating to detected emitted light are transmitted off of the chip through the electrical contacts.