The dP and dZ bases increase the chemical repertoire of nuleic acids for aptamer selections . Of special note is the NO2 group present on dZ.
The figure below shows one application of AEGIS for the selection of aptamers specific to a cell surface protein on a cancer cell.
Biondi et al., 2016; Sefah et al., 2014; Zhang et al., 2015, 2016