Two high-frequency mutual inductance bridges with high resolution

Two mutual inductance bridges are described for operation up to about 100 kHz. Special attention is paid to the sensitivity and resolution of the bridges. Both bridges can be used to measure variations of about 10 pH in the mutual inductance. The first bridge consists of passive elements only whereas the second bridge is equipped with active circuits

Glucose sensor based on the LUQUEN-principle

A new type of glucose sensor based on luminescence quenching (LUQUEN) is proposed. In this LUQUEN principle the concentration induced quenching is enlarged by radiationless (excited-state) energy transfer within the luminescent material. We describe the integrated optical detection part and the chemo-optical interface, in which the concentration induced optical changes are based on the binding of glucose. Some experiments on the internal energy transfer are reported, and the results are discussed

Chromoionophores in optical ion sensors

The feasibility of surface plasmon resonance (SPR) for ion sensing has been investigated. Emphasis is laid on a simulation-based optimization of the SP carrying structure, as well as the applicability of a specific chemo—optical interface we have developed. A preliminary result is presented

Surface plasmon dispersion and luminescence quenching applied to planar waveguide sensors for the measurement Of chemical concentrations

Two novel types of planar waveguide sensors for the chemical domain are introduced. Both are realized by thin film technologies. They consist of multilayered structures coated by a very thin organic overlayer that is able to absorb the species to be measured out of the environment. This absorbtion results in a change in its dielectric function. In the first sensor to be demonstrated this change is measured using a surface plasmon mode as a probe. In the second one the radiationless energy transfer from luminescent centres incorporated in one of the layers to the overlayer serves as a probe