Abstract: Method of quantifying an analyte in a liquid medium by means of magnetic particles functionalized by specific ligands of the analyte being quantified, consisting in applying a magnetic field to a liquid medium for a time period several times shorter than that of the reaction between the analyte being quantified and the ligands of the magnetic particles, in measuring the optical density of the liquid medium after applying the magnetic field, in repeating this cycle of applying the magnetic field and of measuring the optical density several times over the duration of the reaction between the analyte and the ligands, in calculating, by extrapolation, a limiting value for the optical density for an infinite magnetic field application time and in deducing therefrom the concentration of the analyte in the liquid medium.

Abstract: Method of quantifying an analyte in a liquid medium by means of magnetic particles functionalized by specific ligands of the analyte being quantified, consisting in applying a magnetic field to a liquid medium for a time period several times shorter than that of the reaction between the analyte being quantified and the ligands of the magnetic particles, in measuring the optical density of the liquid medium after applying the magnetic field, in repeating this cycle of applying the magnetic field and of measuring the optical density several times over the duration of the reaction between the analyte and the ligands, in calculating, by extrapolation, a limiting value for the optical density for an infinite magnetic field application time and in deducing therefrom the concentration of the analyte in the liquid medium.

Abstract: The invention relates to a method for the extraction of nucleic acids from microorganisms and to the use thereof in a method for the analysis of a microbial population in a given environment, e.g. a population of microorganisms taken from the air. In particular, the invention relates to an extraction method in which the following three lysis steps are performed successively in any order, namely: (i) chemical lysis of the microorganisms, consisting in bringing the microorganisms into contact with a lysis solution containing a detergent; (ii) thermal shock lysis comprising the incubation of the extract at a temperature lower than 0° C., immediately followed by the incubation of the extract at a temperature of at least 95° C. and preferably 100° C.; and mechanical lysis in which the extract is stirred in the presence of balls.

Abstract: An immunoassay apparatus is provided comprising coaxial rotating trays (14) supporting reaction dishes (18) and (16) supporting tubes (24) containing samples to be analyzed, means for driving the trays in rotation about a common axis, and means (280 supporting reagents, extending in an arc around the rotating trays.