In this article we present a very simple, transducer-independent label-free optical detection method based on reflectometry for bioanalytical applications. A laboratory setup of this 1λ-reflectometry delivers results that are comparable with established detection principles like Surface Plasmon Resonance or Reflectometric Interference Spectroscopy. Additionally we present a first version of a miniaturized setup of this method to show its potential due to its simplicity.
This article is presenting results of label-free detections of
biochemical interactions with a simple optical reflectometric
concept. While other label-free detection methods need special
dimensioned transducers and a high device-related effort, this new
principle is working with only one optimal wavelength and is getting
qualitatively good results which are absolutely comparable to
already established detection methods. We show among other things
that it is possible to detect antigene-antibody binding as well as
DNA-DNA hybridizations on low cost plastic transducers with this
simple 1λ-reflectometry concept.
We have demonstrated the feasibility of obtaining intense blue-to-violet electroluminescence (EL) from silicon-based light-emitting structures at room temperature (RT), in line with the need for efficient and inexpensive light sources whose production is compatible with existing silicon device technology. Ion-beam synthesis (IBS) and standard silicon processing have been used to fabricate light-emitting diodes whose active medium is a layer of thermal SiO2 containing germanium nanocrystals. Extensive research has been carried out in three main directions: optimization of the fabrication process, improvement in the device lifetime, and elucidation of the underlying mechanisms of light emission and charge injection/charge transport. This research effort has resulted in the establishment of a set of optimum conditions for the formation of improved-quality Si-based light emitters. It has been shown that the use of plasma treatement is helpful in increasing device lifetime. Issues related to the nature and the excitation of the light-emitting centers have been considered. Finally, the utility of such light-emitting devices in the development of integrated optoelectronic devices as well as Lab-on-a-Chip, microarray and sensor systems has been outlined.