Patent ID: 8883691

Claim:
A method of detecting a biological analyte comprising: (a) delivering a sample suspected of containing a biological analyte to a system, wherein the system comprises a plurality of encoded microparticles, and wherein an encoded microparticle comprises: (i) an elongated body comprising a plurality of alternating portions of a more transparent material and a less transparent material, wherein the portions of the less transparent material are adjacent to the portions of more transparent material, and wherein the portions of the more and less transparent materials form a spatial code which is detectable; and (ii) an outer surface encapsulating the spatial code comprised of glass, silica, silicon dioxide, quartz, silicon nitride, silicon carbide or mixtures thereof; wherein the microparticle has a consistent external cross section shape along a length of the microparticle; (b) determining the spatial code for individual microparticles; and (c) determining the presence or absence of a biological analyte by quantifying signals from the plurality of encoded microparticles.