RESUMO
A compact integrated optical sensor system for a large variety of different (bio-) chemical applications using replicated sensor chips is described. Features of the refractometric system to be emphasized for practical applications include a high-resolution window that can be positioned within a wide measuring range, an in situ chip testing and characterization procedure, and on-chip referencing. As an application example, experimental results on refractometric measurements as well as on the suppression of non-specific binding are given.
Assuntos
Técnicas Biossensoriais , Óptica e FotônicaRESUMO
A novel miniature integrated-optical sensor for versatile multichannel applications is described. Wavelength-modulation techniques using laser diodes (vertical-cavity surface-emitting lasers) are used to interrogate multiple-waveguide sensing regions on a single integrated-optical chip for accurate measurement of effective refractive-index changes at a high data rate. With the experimental miniature sensor system, a resolution of DN(PP) = 10(-7) (short term, peak to peak) of the effective refractive index was demonstrated. In terms of surface-mass coverage, this resolution corresponds to D?(PP) = 130 fg/mm(2).
RESUMO
A novel approach for accomplishing robust integrated optical biosensors is presented. The principle is based on a symmetric grating coupler structure with the inherent feature of compensating disturbances originating from different kinds of mechanical instabilities. The complete sensor system has no moving parts and provides the high sensitivities typical for integrated optical sensors based on grating couplers. The feasibility of this approach is demonstrated by determining the refractive index of liquids as well as by measuring the specific binding of biomolecules (anti-chicken IgG) to immobilized chicken IgG on the sensor chip surface.