IMMOBILIZATION OF BIOMOLECULES ON LANGMUIR-BLODGETT-FILMS OF REGENERATIVE CELLULOSE DERIVATIVES

We present a new and fast method for preparation of ultrathin layers o f biomolecules on solid substrates and its application as a useful too l for sensing biomolecules in an affinity biosensor. Nonamphiphilic tr imethylsilyl ether-cellulose monolayers are used as interfaces to redu ce nonspecific interactions between solid surfaces and biomolecules. T hese films are transferred on optical waveguides by the Langmuir-Blodg ett technique. After their stabilization by cleavage of the hydrophobi c trimehylsilyl groups, the cellulose films serve as excellent matrixe s for the immobilization of proteins at high density. Cyanurchloride s erves as a cross-linker between the cellulose layer and the proteins. The activity and biological specificity of these interfaces is control led by an enzymatic assay and direct sensing by an evanescent wave imm unosensor.