A method of detecting and/or quantitating an analyte of interest in a plurality of biological liquid samples, said method comprising a sample-specific process part, followed by a generic process part; said sample-specific process part comprising the following steps: - separately providing, in any order, a plurality of different biological liquid samples which had been taken and are suspected of containing an analyte of interest, and a plurality of differently labelled subsets of porous microparticles, wherein, in said plurality of subsets, each of said subsets is separate from the other subsets; - specifically labelling each of said different biological samples by separately exposing each of said separate subsets of microparticles to one biological liquid sample each, thus allowing each sample to be taken up by one specifically labelled subset of porous microparticles in an aqueous environment; - separately transferring each subset of porous microparticles from said aqueous environment to a non-aqueous environment; said generic process part comprising the steps: - mixing together the differently labelled subsets of porous microparticles in said non-aqueous environment and thus generating a suspension of a plurality of differently labelled subsets of porous microparticles therein; - performing a detection reaction for detecting said analyte of interest, on said suspension of said plurality of differently labelled subsets of porous microparticles; and - detecting and/or quantitating said analyte of interest, if present, in any of said differently labelled subsets of suspended microparticles; wherein each of said porous microparticles has a porous matrix which allows to accumulate analyte of interest by binding to analyte through: (i) a polymer or polymer mixture that forms or is said porous matrix; or (ii) at least one ionisable group, or a plurality of ionisable groups, immobilized on said porous matrix, said ionisable group(s) being capable of changing its(their) charge(s) according to ambient conditions surrounding said microparticle(s); or (iii) at least one charged group, or a plurality of charged groups immobilized on said porous matrix; or (iv) a combination of any of (i) - (iii). - separately providing, in any order, a plurality of different biological liquid samples which had been taken and are suspected of containing an analyte of interest, and a plurality of differently labelled subsets of porous microparticles, wherein, in said plurality of subsets, each of said subsets is separate from the other subsets; - specifically labelling each of said different biological samples by separately exposing each of said separate subsets of microparticles to one biological liquid sample each, thus allowing each sample to be taken up by one specifically labelled subset of porous microparticles in an aqueous environment; - separately transferring each subset of porous microparticles from said aqueous environment to a non-aqueous environment; said generic process part comprising the steps: - mixing together the differently labelled subsets of porous microparticles in said non-aqueous environment and thus generating a suspension of a plurality of differently labelled subsets of porous microparticles therein; - performing a detection reaction for detecting said analyte of interest, on said suspension of said plurality of differently labelled subsets of porous microparticles; and - detecting and/or quantitating said analyte of interest, if present, in any of said differently labelled subsets of suspended microparticles; - mixing together the differently labelled subsets of porous microparticles in said non-aqueous environment and thus generating a suspension of a plurality of differently labelled subsets of porous microparticles therein; - performing a detection reaction for detecting said analyte of interest, on said suspension of said plurality of differently labelled subsets of porous microparticles; and - detecting and/or quantitating said analyte of interest, if present, in any of said differently labelled subsets of suspended microparticles; wherein each of said porous microparticles has a porous matrix which allows to accumulate analyte of interest by binding to analyte through: (i) a polymer or polymer mixture that forms or is said porous matrix; or (ii) at least one ionisable group, or a plurality of ionisable groups, immobilized on said porous matrix, said ionisable group(s) being capable of changing its(their) charge(s) according to ambient conditions surrounding said microparticle(s); or (iii) at least one charged group, or a plurality of charged groups immobilized on said porous matrix; or (iv) a combination of any of (i) - (iii). (i) a polymer or polymer mixture that forms or is said porous matrix; or (ii) at least one ionisable group, or a plurality of ionisable groups, immobilized on said porous matrix, said ionisable group(s) being capable of changing its(their) charge(s) according to ambient conditions surrounding said microparticle(s); or (iii) at least one charged group, or a plurality of charged groups immobilized on said porous matrix; or (iv) a combination of any of (i) - (iii).