A new SELEX scheme is proposed for the selection of aptamers targeting a specific epitope of a native protein. Anti-sialic acid receptor (SAR) aptamers that inhibit H1 hemagglutination at a low picomole dose are selected accordingly.

can be reduced by modifying the electrode with graphene. Like in superconductors, electrons can flow across graphene nearly without scattering, which is crucial for constructing ultrasensitive-sensors. Therefore, understanding the interaction between the GOx and graphene is of prime importance. To this end, we have employed small angle neutron scattering technique to investigate the structural features of GOx covalently attached to the single layer graphene (SLG). Two different samples varying in density are examined and a 3-level Unified Fit is used to quantify the structural details. It is interesting to note that the radius of gyration of the primary protein reduced from~30 Å in solution to about~21-22 Å on the SLG, possibly indicating the disruption in the integrity of GOx's quaternary structure. Further, though the increase in the GOx concentration resulted in similar structural topology, the clusters displayed a smoother surface with fractals of higher density.