Sensor and method for determining a property of each of a plurality of liquids

A sensor for determining a property of each of a plurality of liquids includes a plurality of electromagnetic radiation sources, each source generating a beam of electromagnetic radiation. The sensor also includes an array of electromagnetic radiation detectors. Each detector in the array is responsive to detect part of the beam of electromagnetic radiation generated by each source for making a determination of a property of the part of the beam detected. The sensor further includes a surface plasmon resonance layer and a reflecting surface. The surface plasmon resonance layer has a first surface and a second surface. The first surface can have a plurality of liquids deposited thereon, and the second surface reflects at least part of the beam of electromagnetic radiation generated by each source. The reflecting surface reflects the electromagnetic radiation reflected from the surface plasmon resonance layer towards the array of detectors. The response of the detectors for each beam determines the property of each liquid.