engleski

Monitoring of formation of polyelectrolyte-protein multilayers using optical reflectometry

It is known that the layer-by-layer deposition method for preparation of multilayers of polyelectrolytes of alternating charge can be followed in situ by means of stagnation point optical reflectometry. The possible use of the same method for the monitoring of formation of multilayers obtained by exposing a suitable substrate to solutions of a cationic homopolymer and an oppositely charged protein was investigated. In all presented experiments the protein used was Bovine Serum Albumine, and as the cationic homopolymer either poly(dimethylaminoethyl)methacrylate (PAMA) or poly(2-vinyl-n-methylpyridinium iodide) (PVP+) were used. As the solid substrate we used silica in the form of silicon wafers carrying an oxide layer, and as the electrolyte (ordinary salt) we used potassium chloride and the mixture of Na2HPO4 and NaH2PO4. The influence of the type of cationic homopolymer (strong or weak polyelectrolyte), protein concentration, electrolyte type, ionic strength and pH was investigated. It was shown that stagnation point optical reflectometry can be a useful tool in the process of monitoring the formation of multilayers containing polyelectrolyte and protein layers.

polyelectrolyte-protein multilayers ; optical reflectonetry ; bovine serum albumin

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