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The represented work is aimed at the problem of optimization of optical biosensors based on the surface plasmon
resonance (SPR) effect in thin gold films. Using it, one can characterize biomolecular interactions by detection of the
resonance angle shift in a real time scale without any labels.
To provide reliable operation of a sensor chip, we deposited a sensitive gold film onto glass substrates using an
intermediate chromium layer capable to improve adhesion of the following layers. Performed is the analysis of the
chromium layer influence on structural and optical properties of the gold film as well as on processes of transducer
regeneration after operation cycles.
The influence of low-temperature annealing (80÷300°C) on gold film properties was investigated. As it was observed with
SPR spectroscopy and atomic force microscopy, minimal energy losses during excitation of surface polariton states as well
as smoothing the small-scale relief of polycrystalline gold surface are reached with annealing temperatures close to 120°C.
It is these samples that provide formation of defectless self-organized thiol monolayers, which results in stabilization and
passivation of SPR transducer sensitive surface.
Modification of the transducer gold surface with a monolayer matrix system containing two types of mercaptanes of
different lengths and structure enabled to realize the idea of molecular recognizing some low-molecular compounds
(barbituric acid) against the background of close structural analogs (veronal).
To avoid influence of non-specific sorption, for the first time, we used the electrochemically deposited films of nickel
hydroxide Ni(OH)2.
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