Protein A Grids provide a radical new approach to sample preparation for electron microscopy of
biomolecules. In essence, Protein A Grids are an affinity platform for small-scale isolation and purification
of immunoglobulins and immunoprecipitation of proteins and viruses directly on the grid surface.
Protein A exhibits high affinity for subclasses of IgG from many species including human,
rabbit and mouse (1). Binding of IgG occurs mainly through the Fc region which increases
the concentration of exposed antigen binding sites on the grid surface . Protein A Grids
utilize Protein A purified from S. Aureus that is covalently coupled to the SMART Grids
surface. The linkage is stable over a wide pH range that permits the immunoprecipitation
of target proteins from crude cell lysates using a selected primary antibody. The binding
capacity of the grid will depend on the initial concentration of antibodies in the sample
and the source of the antibody.
Protein A Grids dramatically simplify sample preparation by eliminating the need for columns, centrifugations, or
time-consuming purification and pre-treatment of your samples. Starting sample can be saliva, plasma, ascites,
serum, and tissue culture or hybridoma supernatants. Total sample preparation time is less than 30 minutes for
most samples. A simple step-by-step protocol is included with Protein A grid purchase. User must supply antibody.
Protein A Grids can be used in a wide variety of applications including single particle analysis, viral diagnostics, cryoEM, wet-STEM, and structural biology.
To order SMART Grids, please make your selection below. For assistance in selecting the correct window size and thickness for
your applications, see our configuration page.