Abstract: A process for the selective binding of an aggregating abnormal form of a protein in the presence of the nonaggregating normal form of the protein, including contacting under selective binding conditions a material containing both the abnormal and normal forms with a binding agent which is a polyionic material having a binding avidity for the aggregating form of the protein as present in the sample.

Abstract: Aggregating proteins such as IgG, are bound selectively in the presence of the non-aggregated protein using a polyionic binding agent such as dextran sulphate or pentosan (anionic), or polyamine compounds such as pDADMAC (cationic) under selective binding conditions including the use of n-lauroylsarcosine at mildly alkaline pH, and may then be assayed.

Abstract: A process for the selective binding of an aggregating abnormal form of a protein in the presence of the nonaggregating normal form of the protein, including contacting under selective binding conditions a material containing both the abnormal and normal forms with a binding agent which is a polyionic material having a binding avidity for the aggregating form of the protein as present in the sample.

Abstract: Infective aggregating forms of proteins such as PrP, amyloid, and tau are bound selectively in the presence of the normal form protein using a polyionic binding agent such as dextran sulphate or pentosan (anionic), or polyamine compounds such as pDADMAC (cationic) under selective binding conditions including the use of n-lauroylsarcosine at mildly alkaline pH, and may then be assayed.

Abstract: The present invention relates to a method for detecting a target material in a sample, which method comprises the steps of: a) exposing a sample, expected to contain that target material, to at least two viruses which are capable of binding directly or indirectly with that target material so as to form a virally bound target material and to endow the virally bound target material with a distinctive property; and b) cultivating the product from stage a in the presence of an indicator material to which the viruses carried by the virally bound target material attach so as to cause the indicator material to adopt the distinctive property of the virally bound target material; and c) monitoring the presence or otherwise of virally attached indicator material. The invention also provides a kit for use in the method of the invention.