Encoding of microcarriers

A method of encoding a microcarrier that includes a bleachable portion having a bleachable substance, the bleachable portion located on a surface of the microcarrier or at an internal depth of the microcarrier, wherein the method of encoding comprises:

• exposing the microcarrier to a high spatial resolution light source;
• and
• forming a bleached pattern at the bleachable portion of the microcarrier to write a code associated with the microcarrier, said bleached pattern formed by bleaching a plurality of sites of the bleachable portion of the microcarrier, wherein at least two of the sites of the bleachable portion are bleached to different degrees such that the at least two sites of the bleachable portion have different levels of luminescent intensity,
• wherein the code is provided by (i) a geometry of the bleached pattern and (ii) the different levels of luminescent intensity within the bleached pattern.

A method of detecting the presence or absence of one or more target analytes in a sample, the method comprising:

• selecting one or more ligands that bind or react with the one or more target analytes;
• binding at least one of the ligands to a plurality of encoded microcarriers, each encoded microcarrier including:
• a body having a surface and an internal depth;
• a bleachable portion having a bleachable substance, said bleachable portion located on the surface or at the internal depth of the body;
• and
• a bleached pattern at the bleachable portion for providing a code, the bleached pattern comprised of a plurality of sites in the bleachable portion, wherein at least two of the sites in the bleachable portion are bleached to a different degree such that the at least two sites of the bleachable portion have different levels of luminescent intensity,
• wherein the code is provided by (i) geometry of the bleached pattern and (ii) the different levels of luminescent intensity within the bleached pattern;
• correlating the identity of the ligands with the respective codes of the plurality of encoded microcarriers to which the ligands are bound;
• contacting the one or more target analytes with the plurality of encoded microcarriers;
• observing any encoded microcarriers upon which the target analyte has bound or reacted with at least one ligand bound to the encoded microcarriers;
• and
• reading the codes of the plurality of encoded microcarriers to identify any ligands with which the one or more target analytes have reacted, thereby determining the presence or absence of the one or more target analytes.

A method of detecting the presence or absence of one or more target analytes in a sample, the method comprising:

• contacting an encoded microcarrier with at least one target analyte, wherein the encoded microcarrier includes:
• a body having a surface and an internal depth;
• a bleachable portion having a bleachable substance, said bleachable portion located on the surface or at the internal depth of the body;
• and
• a bleached pattern at the bleachable portion for providing a code, the bleached pattern comprised of a plurality of sites in the bleachable portion, wherein at least two of the sites in the bleachable portion are bleached to a different degree such that the at least two sites of the bleachable portion have different levels of luminescent intensity,
• wherein the code is provided by (i) geometry of the bleached pattern and (ii) the different levels of luminescent intensity within the bleached pattern;
• detecting whether the target analyte has reacted or bound to a ligand on the encoded microcarrier;
• and
• reading the code of any encoded microcarrier upon which any reaction or binding has occurred.

A chemical library, comprising:

• a plurality of encoded microcarriers, each encoded microcarrier including:
• a body having a surface and an internal depth;
• a bleachable portion having a bleachable substance, said bleachable portion located on the surface or at the internal depth of the body;
• and
• a bleached pattern at the bleachable portion for providing a code, the bleached pattern comprised of a plurality of sites in the bleachable portion, wherein at least two of the sites in the bleachable portion are bleached to a different degree such that the at least two sites of the bleachable portion have different levels of luminescent intensity,
• wherein the code is provided by (i) geometry of the bleached pattern and (ii) the different levels of luminescent intensity within the bleached pattern;
• wherein the plurality of encoded microcarriers contain one or more ligands bound thereto;
• and
• a plurality of individual members of said chemical library, wherein said individual members are bound to said plurality of encoded microcarriers.