Purification of multi-specific receptors

Abstract

Disclosed is a method for preparing a composition enriched for receptors (typically molecular impringet polymers, MIPs) that bind an agent, where said receptors each specifically bind at least two discrete sites on said agent, by subjecting a sample of receptors to a first step of affinity purification with the agent where one binding site on the agent is non-accessible for binding to the receptors and subsequently subjecting the purified receptors to at least one further step of affinity purification with the agent where a second binding site on the agent is non-accessible. Also disclosed is a method for treatment, amelioration or prophylaxis of a disease selected from the group consisting of phenylketonuria (PKU, Følling's disease), hyperphenylalaninemia (HPA), alcaptonuria (black urine disease), tyrosinemia, hypertyrosinemia, myasthenia gravis, histidinemia, urocanic aciduria, maple syrup urine disease (MSUD), isovaleric acidemia (isovaleryl-CoA dehydrogenase deficiency), homocystinuria, propionic acidemia, methylmalonic acidemia, and glutaric aciduria Type 1 (GA-I), galactosemia, comprising administering to the gastrointestinal tract of a patient in need thereof an effective amount of a composition of molecular imprinted polymers (MIPs), said composition being capable of binding a symptom provoking agent of said disease.