also shown that it is possible with certain chemical substances to manipulate e g lower the 34 cloud point 34 for example by adding sodium sulphate to 0 2m the invention is characterized in that the collection polymer is a water soluble polymer having a cloud point in the range 5 u00b0 90 u00b0 c preferably 10 u00b0 60 u00b0 c especially 12 u00b0 25 u00b0 c research concerning the usefulness of temperature induced phase separation as a separation method for macromolecules and particles such as cells is today very rudimentary dapral t 210 akzo the netherlands is a chemically modified dialkyl polyglycol ether which has a molecular weight of about 8 000 presents temperature induced phase separation the polymer has a central hydrophilic part which is diisocyanate ethylene diamine diurethane part to which ethylene oxide and propylene oxide is polymerized in both ends the result is a polymer having hydrophobic ends and a hydrophilic central part the polymer can be mixed with water in concentrations down to 5 at room temperature below this concentration the polymer phase separates fig2 on phase separation the polymers bind comparatively great amounts of water compared to e g ucon together with an aqueous solution of polyethylene glycol or a polyoxyalkylene glycol ether there will be formed a system having a top phase which is rich in polyethylene glycol or alternatively a polyoxyalkylene glycol and a bottom phase which is rich in dapral t 210 in this system the lower phase will however be more hydrophobic to the upper phase i e the opposite condition compared to traditional two phase separation like in the distribution in traditional two phase systems the separation between the phases will be influenced by hydrophilic hydrophobic interactions between the phase polymer polymers and the soluble macromolecules and or.