The present application discloses a composition comprising a plurality of spherical beads, wherein a radiofrequency
chip operating at a frequency of in the range of 2.2-2.7 GHz is embedded within each of said beads and wherein essentially each of said beads is individually identifiable on the basis of radiofrequency identification. Alternatives utilizing a ultrasonic identification
chip are also disclosed. The beads are preferably made of polymeric material and can for example be used for the synthesis of e.g.
solid-phase chemical libraries. Preferred materials include some that minimise interference in biochemical assays (
fouling). The invention also relates to batch and continuous methods of producing such compositions, including
emulsion-polymerisation methods. In a further aspect, the present invention relates to an apparatus for analysing radiofrequency-encoded beads. Also provided are methods for detecting and / or analysing and / or sorting beads, as well as methods for
processing beads once they have been analysed and / or sorted.