Thin layer composite molecularly imprinted membranes for selective separation of cAMP

Composite microfiltration membranes imprinted with adenosine 3′:5′-cyclic monophosphate (cAMP) were developed using photoinitiated copolymerisation of a functional monomer (diethylaminoethylmetacrylate (DEAEM), 2-hydroxyethyl methacrylate (HEMA), methacrylic acid (MA) and trimethylopropanethrimethacrylate (TRIM)) as crosslinker in the presence of cAMP as template, followed by a deposition of molecular imprinted polymer layer (MIP) on the surface of polyvinilidene fluoride (PVDF) membranes. As a result, membranes covered with a thin layer of imprinted polymer selective to cAMP were obtained with different degrees of modification. The effects of the type and concentration of the functional monomer, as well as the crosslinker's concentration, on the binding of cAMP on MIP membranes have been evaluated. It was concluded that MIP membranes binding capability is a result of both multi-sites binding to the template via hydrogen bonding and the correct position of functional groups involved in binding in imprinted polymer. Profile imaging mode atomic force microscopy has been used to visualise the surface structure of molecularly imprinted membranes and to quantify pore size and surface characteristics.