Abstract: A method and an apparatus for determining the coverage of the interface between a liquid first phase and a liquid or gaseous second phase by at least one molecular species, at least the following procedural steps being carried out successively: the generation of a stream of droplets which contain at least the liquid first phase, in such a way that the droplets move along a droplet trajectory, and the non-contact determination of a measure of the coverage of the interface by the at least one molecular species at at least two different points along the droplet trajectory.

Abstract: A method and an apparatus for determining diffusion parameters, concentration, size or flow behavior of particles in a sample, exciting light of a light source being directed into the sample, Raman scattered light being collected from an observed volume of the sample and being passed on to a spectrograph where it is resolved into spectral lines, the intensity of at least one spectral line being measured at least 10 times per second by means of one photodetector each, and the measured intensity values for the respective spectral line being used, via a fluctuation analysis, preferably an autocorrelation or a frequency analysis, to calculate diffusion parameters, concentration, size or flow behavior of the particle to which the spectral line in question can be assigned. With this method, it is also possible for signals of different spectral lines or bands, or signals of Raman scattered light, quasi-elastically scattered light and fluorescence light to be correlated with one another.

Abstract: An apparatus for carrying out laser-induced two-photon fluorescence correlation spectroscopy (TPA-FCS), in which a plurality of volumes (6) are delimited or defined in the apparatus in such a way that samples (3) introduced into these volumes can be excited and observed in parallel by means of a single laser (1). Such an apparatus is e.g. used to screen active compounds.