Particle display: a quantitative screening method for generating high-affinity aptamers.We report an aptamer discovery technology that reproducibly yields higher affinity aptamers in fewer rounds compared to conventional selection.  Our method (termed particle display) transforms libraries of solution-phase aptamers into "aptamer particles", each displaying many copies of a single sequence on its surface.  We used particle display to obtain high-affinity DNA aptamers for four different protein targets in three rounds, including proteins for which previous DNA aptamer selection efforts have been unsuccessful.  We believe particle display offers an extraordinarily efficient mechanism for generating high-quality aptamers in a rapid and economic manner, towards accelerated exploration of the human proteome.
particle display
We then use fluorescence-activated cell sorting (FACS) to individually measure the relative affinities of >10(8) aptamer particles and sort them in a high-throughput manner. 
FACS