Barcoded Beads and Method for Making the Same by Split-Pool Synthesis

A method for adding oligonucleotides onto beads, comprising:

• (a) splitting a pool of beads into a plurality of reaction volumes;
• (b) appending oligonucleotides onto the beads in the reaction volumes, wherein at least some of the reaction volumes each receive an oligonucleotide that contains a sequence that is different from the other oligonucleotides added to the reaction volumes;
• (c) pooling the beads;
• and
• (d) repeating steps (a)-(c) one or more times to produce a pool of beads that comprise nucleic acid tags,
• wherein in the one or more repeats of step (d) the oligonucleotides that are appended in step (b) are added to previously appended oligonucleotides to form the nucleic acid tags.

A method comprising adding oligonucleotides onto beads by a split-pool process, wherein the split-pool process comprises multiple rounds comprising the following steps, performed in order:

• (i) splitting the beads;
• (ii) adding the oligonucleotides to nucleic acids on the beads while beads are split;
• and
• (iii) pooling the beads.

A population of beads, comprising:

• (a) a first bead associated with a first nucleic acid, wherein the first nucleic acid comprises a first tag that comprises a first plurality of ordered oligonucleotides;
• and
• (b) a second bead associated with a second nucleic acid, wherein the second nucleic acid comprises a second tag that comprises a second plurality of ordered oligonucleotides;
• wherein the sequences of the first and second tags are different.