Ribosome display is a method of cell-free selection and evolution from very large libraries that we have devised and that is now widely used. Since there is no transformation of cells involved, much larger libraries can be screened than with other technologies. Ribosome display has affinity maturation built in, as the errors of a PCR can be exploited, or error-prone PCR can be used to increase the error rate. Ribosome is thus a true in-vitro Darwinian evolution.
Ribosome display has been adapted to a high-throughput mode, where 96 different selections can be done in parallel. It has also been adapted to affinity maturation of individual clones (reaching a monovalent dissociation constant of 1 pM), improvement of protein stability.