The invention relates to a method and test kit for the detection of analytes in a biological sample, wherein at least one microparticle population is labelled with fluorescent dyes serving as coding fluorescent dyes and reference fluorescent dyes and immobilized, acceptor molecules interacting with labelled analytes being bound to the microparticle population, so that the difference between the fluorescence of the microparticles and analyte(s) can be used to determine which kind of analyte, optionally in which amount, is present in the sample. In particular, the invention finds use in medical diagnostics.