A noninvasive electronic sensor designed to be used by a healthcare professional for the transcutaneous activation and detection of a pre-injected fluorescent tracer agent in tissues to facilitate point-of-care glomerular filtration rate (GFR) measurements. It includes a light(s) for tracer agent fluorescence activation and photodiodes for light detection. It is attached to the patient at the skin surface and connected to a dedicated analyser (not included) for GFR measurements. This is a reusable device.