A method of isolating a biological entity from a sample comprising (i) providing a sample comprising the biological entity , wherein the biological entity comprises a surface antigen ; (ii) providing a tagging agent comprising at least one binding domain capable of specifically binding to the surface antigen on the biological entity; (iii) providing freely movable beads , wherein the beads are non-magnetic beads, preferably agarose beads; and (iv) incubating the sample, tagging agent and beads within a container and allowing complex formation between the biological entity , the tagging agent and the beads while the beads float within the sample, wherein the binding of the biological entity via the tagging agent to the beads is indirectly mediated by non-covalent protein-ligand interaction comprising a ligand binding partner and a ligand ; and (v) purifying the biological entity by comprising temporarily holding the beads in place in the container, while discarding the supernatant, and adding a washing buffer; and/or (vi) isolating the biological entity by releasing the biological entity from the beads and the tagging agent , respectively, and recovery of the biological entity from the supernatant while temporarily holding the beads in place in the container, optionally allowing for the recovery of the tagging agent and/or beads , wherein the tagging agent is immobilized on the beads via a linking molecule which comprises an antigen recognized by the tagging agent and a component for said non-covalent protein-ligand interaction, wherein the component is the ligand and wherein the beads comprise the ligand binding partner , and wherein the method comprises at least two tagging agents capable of recognizing the surface antigen and the recombinant antigen comprised in the linking molecule, wherein the tagging agents are immobilized on a carrier by non-covalent protein-ligand interaction, wherein the non-covalent protein interaction is mediated between the ligand of the tagging agent and the ligand binding partner on the carrier . (i) providing a sample comprising the biological entity , wherein the biological entity comprises a surface antigen ; (ii) providing a tagging agent comprising at least one binding domain capable of specifically binding to the surface antigen on the biological entity; (iii) providing freely movable beads , wherein the beads are non-magnetic beads, preferably agarose beads; and (iv) incubating the sample, tagging agent and beads within a container and allowing complex formation between the biological entity , the tagging agent and the beads while the beads float within the sample, wherein the binding of the biological entity via the tagging agent to the beads is indirectly mediated by non-covalent protein-ligand interaction comprising a ligand binding partner and a ligand ; and (v) purifying the biological entity by comprising temporarily holding the beads in place in the container, while discarding the supernatant, and adding a washing buffer; and/or (vi) isolating the biological entity by releasing the biological entity from the beads and the tagging agent , respectively, and recovery of the biological entity from the supernatant while temporarily holding the beads in place in the container, optionally allowing for the recovery of the tagging agent and/or beads , <EOS>