Noninvasive in vivo real time analyte measurement uses a multitude of sensors binding reversibly to the analyte whereby the response of the sensors to a noninvasive stimulus is altered by their bound versus unbound state. The stimulus and responses are electromagnetic, magnetic or any other suitable forms. The sensors are bound to a blood component providing transport through the body fluids and sensor elimination. A sensor is constructed from proteins or as a nanodevice. A noninvasive device generates the stimulus, senses the responses, determines the measurement, and controls a medication infusion pump. A non-contact device is used for population screening, and one form of such a device is a nuclear magnetic resonance imager. Measurement in fluids other than blood uses a blood component flowing out of blood and into the desired fluid.