Patent ID: 8034397

Claim:
A method of forming an assay device for detecting an analyte in a test sample, the method comprising: providing a plurality of latex particles, wherein the latex particles individually define a polymeric shell about a hollow interior constituting at least about 20% of the spatial volume occupied by the particle, wherein the polymeric shell of the latex particles comprises an organic polymer having carboxylic functional groups, wherein the latex particles have an average size of from about 0.1 nanometer to about 100 microns; activating the carboxylic functional groups on the organic polymer of the polymeric shell to form activated carboxylic functional groups; reacting the activated carboxylic functional groups with an amino group of an antibody to form an amide bond such that the antibody is covalently bonded to the hollow particle; blocking any remaining activated carboxylic functional groups on the organic polymer of the polymeric shell; and incorporating the hollow particles into an assay device.