Analytical apparatus

A method of performing photometric or spectrophotometric analysis of a liquid sample of a volume not more than five microlitres, the method comprising the steps of placing the sample on one of a pair of hydrophobic surfaces so as to be supported on said surface, when said surfaces are in an open condition, moving at least one of the surfaces until the surfaces are in a closed condition, in which the surfaces oppose each other across a gap and the sample is sandwiched between two surfaces, passing a beam of electromagnetic radiation through one of the surfaces and through the sample and hence across the gap between the surfaces, and analysing the beam after it has passed through the sample, wherein the beam, after having passed through the sample, is reflected towards a detector for analysing the beam, by a prism situated on the opposite side of one of the surfaces from the sample.

Apparatus for analysing a liquid sample, the apparatus comprising a beam generator for generating a beam of electromagnetic radiation, a detector for detecting electromagnetic radiation from said generator after the electromagnetic radiation has interacted with the sample, a sample retaining element for releasably retaining the sample in the path of the beam, wherein the sample retaining element comprises a hydrophobic surface on which the sample is, in use, supported, wherein the surface is one of a pair of such surfaces between which, in use, a sample being analysed is sandwiched, at least one of the surfaces is movable so that the surfaces have an open condition in which a sample is applied to or removed from at least one of the surfaces and a closed condition in which the sample is sandwiched between the two surfaces and wherein the apparatus includes an interlock operable to permit operation of the beam generator only when the surfaces are in their closed condition.

Apparatus for analysing a liquid sample, the apparatus comprising a beam generator for generating a beam of electromagnetic radiation, a detector for detecting electromagnetic radiation from said beam generator after the electromagnetic radiation has interacted with the sample and a sample-retaining element for releasable retaining the sample in the path of the beam, wherein the sample-retaining element comprises a hydrophobic surface on which the sample, in use, is supported, wherein the surface is one of a pair of such surfaces between which, in use, a sample being analysed is sandwiched, wherein at least one of the surfaces is movable so that the surfaces have an open condition in which a sample is applied to or removed from at least one of the surfaces, and a closed condition in which the sample is sandwiched between the two surfaces and wherein the apparatus includes a movable stop for defining a minimum distance between the surfaces, when in their closed condition, and a drive for at least one of extending and retracting the stop, automatically to vary the distance in the course of a succession of measurements performed on the sample.