Abstract: The embodiments of the present invention are directed to an automatic apparatus (55), which is designed for performing nucleic acid analysis, optionally including sample preparation, with integrated disposable sample holding and processing devices (1), which devices (1) comprise a sample to be analyzed with the apparatus (55). The apparatus (55) comprises workstations (17, 40) for receiving, holding and processing such integrated disposable devices (1), a reagents station (56) for reagents (25), transfer means (36) for performing movements of an actuator, fluid actuation means for processing the sample (32) and reagents in said disposable devices (1), temperature control means (37) for heating or cooling, detection means for measuring a property of the processed samples (32), and control means for controlling the sample (32) preparation, the handling of the disposable devices (1) and the sample analysis performed by the apparatus (55).

Abstract: A level sensor apparatus is disclosed for detecting contact of a pipetting needle with a liquid contained in a vessel. The apparatus includes a sensor head made up of a pipetting needle, a needle holder, and an electromechanical transducer. The sensor head also has an associated mechanical resonance frequency. An electrical signal generator is used to generate a driving signal which when applied to the electromechanical transducer causes vibration of the pipetting needle at the resonance frequency. A measurement device is used to measure a parameter of a vibration signal indicative of the mechanical vibration of the pipetting needle when it is driven by the driving signal. An electronic circuit and associated computer software is provided to evaluate variation of the vibration signal with time and thus detect contact of the pipetting needle with a liquid contained in the vessel.