Abstract: A method of detecting or determining the sequence of monomers which is a topographical equivalent of the ligand which is complementary to a particular receptor of interest, the method comprising the steps of:1. synthesizing a plurality of catamers, each said catamer being of the general formula:D.sub.2 --D.sub.1wherein D.sub.1 represents a designated monomer selected from a first set of monomers, and D.sub.2 represents a designated monomer selected from a second set of monomers which may be the same as or different to said first set of monomers; said plurality of catamers comprising catamers in which each designated monomer is systematically varied to contain members from the respective set of monomers;2. contacting each catamer with the receptor of interest, and,3. detecting or determining the presence or absence of binding between each catamer and said receptor.

Abstract: A device for use in detecting or determining the presence of antigenic or haptenic substances or antibodies in a sample comprises a plurality of tubular or capillary elements (1, 2, 3, 4, 5, 6), each having antibodies or antigenic or haptenic substances attached to an internal surface thereof, and means (11) for causing fluids to pass simultaneously or sequentially through the plurality of capillary elements. A method and test kit for detecting and determining the presence of antigenic or haptenic substances or antibodies in a sample by the enzyme-linked immunosorbent assay technique is characterized by use of urease as the enzyme in an antibody-enzyme or antigen-enzyme conjugate, with urea being used as the enzyme substrate and the presence of ammonia being detected or determined using di-bromo-o-cresolsulfonphthalein.

Abstract: A synthetic peptide which displays the antigenicity of the VP1 protein of foot-and-mouth disease virus, characterised in that at least a portion of said peptide is selected from the group consisting of five-, six- or seven-long antigenically active amino acid sequences of said VP1 protein, and antigenically active modified sequences thereof.

Abstract: A method and test kit are disclosed for detecting the presence of antigens or antibodies in a sample by an enzme-linked immuno-sorbent assay using urease as the enzyme, urea as the enzyme substrate and di-bromo-o- cresolsulfonphthalein as the indicator.