A mains electricity (AC-powered) laboratory instrument intended to be used for the qualitative and/or quantitative simultaneous determination of multiple chemical and/or biological markers in a single clinical specimen using an immunological method which incorporates multiple antibodies arranged on a solid surface (e.g., slide, plate, membrane) or coated to micro-particles. It typically includes a system for the detection of bound target antigen (e.g., chemiluminescent, fluorescent, photometric, magnetic detector), together with sample processing, data processing and data display software. It operates with minimal technician involvement and complete automation of all procedural steps.