UniFilter-96 PEI-coated GF/C, White 96-well SAN Microplate with 1.2 µm pore size GF/C filter. The GF/C UniFilter Microplates are made of a chemically resistant Styrene AcryloNitrile (SAN) resin, which is compatible with most liquid scintillation counting cocktails. SAN resin replaces microplates previously made with Barex^® resin.

GF/C glass fiber filter-bottom 96-well microplate, for cell harvesting assays using a vacuum manifold. These plates are designed with a built-in glass fiber filter for receptor binding assays or cell harvesting using a manifold.

Polyethyleneimine (PEI) is a cationic polymer that can neutralize the negative charge of glass fiber filters (GF/C, GF/B). Treating GF/C and GF/B filter plates with polyethylenimine (PEI) is often used to minimize non-specific binding, particularly in ligand-binding assays. For some applications involving negatively-charged ligands (such as GTP binding assays), PEI coating could cause problems by creating a positively-charged surface that actually promotes non-specific binding to the filter, due to the negative charge on the ligand.