Wide-field extrinsic optical signal imaging of fluorescence potassium sensors

Wide-field extrinsic optical signal (EOS) imaging is an excellent method for its spatial resolution of 50-100 mum and a wide imaging field of several mm that cannot be achieved by any microscope. Fluorescence images of a nanoengineered sensor for potassium, fabricated by using electrostatic layer-by-layer (LbL) self-assembly technique, were collected by a wide-field EOS imaging system under different concentrations of [K
⁺
]. The images were analyzed using MATLAB to study the quenching properties of the potassium nanosensor