Diffraction grating-based encoded micro-particles for multiplexed experiments

An encoded particle having a chemical attached thereto, comprising:

• a particle;
• at least a portion of said particle being made of a substantially single material and having at least one diffraction grating embedded therein, said grating having a resultant refractive index variation within the substantially single material at a grating location;
• and
• said grating providing an output optical signal indicative of a code when illuminated by an incident light signal propagating from outside the substrate, said output optical signal being a result of passive, non-resonant scattering from said grating when illuminated by said incident light signal;
• and
• the chemical being attached to at least a portion of said particle.

A method of reading an encoded optical identification element having a chemical attached thereto, comprising:

• obtaining a substrate, at least a portion of which being made of a substantially single material and having at least one diffraction grating embedded therein, said grating having a resultant refractive index variation within the substantially single material at a grating location;
• attaching the chemical to at least a portion of said substrate;
• illuminating said substrate with incident light, said substrate providing an output optical signal indicative of a code, said output optical signal being a result of passive, non-resonant scattering from said grating when illuminated by said incident light;
• and
• reading said output light signal and detecting said code therefrom.

A method of reading an encoded particle having a chemical attached thereto, comprising:

• obtaining a particle, at least a portion of which being made of a substantially single material and having at least one diffraction grating embedded therein, said grating having a resultant refractive index variation within the substantially single material at a grating location;
• attaching the chemical to at least a portion of said particle;
• illuminating said particle with incident light, said particle providing an output optical signal indicative of a code, said output signal being a result of passive, non-resonant scattering from said grating when illuminated by said incident light;
• and
• reading said output light signal and detecting said code therefrom.

A method of performing a multiplexed particle assay, comprising:

• obtaining a plurality of particles each being made of a substantially single material and having at least one diffraction grating embedded therein, said grating having a resultant refractive index variation within the substantially single material at a grating location;
• attaching at least one probe to at least one of said particles, thereby providing functionalized particles;
• placing said functionalized particles in contact with at least one analyte, said analyte having a corresponding label disposed thereon;
• illuminating said particles with a first and second incident light, said particle providing a first output optical signal responsive to said first incident light indicative of a code and a second output optical signal responsive to said second incident light indicative of said label, said first output optical signal being a result of passive, non-resonant scattering from said grating when illuminated by said incident light;
• reading said first output optical signal and detecting said code therefrom;
• and
• reading said second output optical signal and detecting said label therefrom.