Patent ID: 8536099

Claim:
A method comprising: washing an array of first beads on a substrate, a surface of which contains a plurality of channels, microwells, or posts, with a wash solution to remove stacked first beads from the substrate, the wash solution comprising from 2% to 50% by weight inert solid beads, the first beads having an average diameter and the solid beads having an average diameter that is at least twice the average diameter of the first beads, the washing dislodging the stacked first beads; and removing the wash solution and the dislodged first beads from the substrate to form a monolayer of first beads disposed in said channels or microwells or between said posts, forming an array, wherein for a channel of said channels, a plurality of the first beads forms a row of first beads in said channel, the row being substantially free of stacked first beads, or wherein for each microwell of a plurality of said microwells or between each set of posts of a plurality of said posts, an individual first bead is disposed substantially free of a stacked first bead.