SURFACE-PLASMON RESONANCE SPECTROSCOPY - PROSPECTS OF SUPERSTRATE REFRACTIVE-INDEX VARIATION FOR SEPARATE EXTRACTION OF MOLECULAR LAYER PARAMETERS

A computational procedure for separate determination of n and d of thi n transparent layers using the surface plasmon resonance (SPR) spectro scopy with variation of the refractive index of the solution and its a pplication to immunic reaction studies are presented. This procedure i s essentially based on a direct fitting of a set of the resonant curve s. Effect of the experimental conditions and measurement errors on the accuracy of the data obtained has been analyzed. Precise measurement of the angle of incidence and the refractive index of the solution wer e found to be important for the correct determination of the layer par ameters. This technique was applied to a mouse IgG and an anti-mouse I gG interaction study. It has been demonstrated that n and d of the mol ecular layer can be determined with reasonable accuracy even using rel atively small variation of the refractive index of the solution. (C) 1 998 Elsevier Science S.A. All rights reserved.