Biomedical subjects

Gerben Boer

Publications and source records attributed to Gerben Boer.

3 recordsLinked to original sources

PubMed2004

Compact liquid-crystal-polymer Fourier-transform spectrometer.

We present the optical design and realization of a low-resolution liquid-crystal (LC) Fourier-transform spectrometer (FTS). This FTS is based on a polarization interferometer that has a Wollaston prism made of a LC material as a key component. It has a compact design, a good acceptance angle, and low temperature dependence and can be fabricated with cost-effective LC technology. Because the LC is polymerized, it is robust, and the temperature dependence is drastically reduced. The performance of a compact handheld version of the spectrometer and the characteristics (angular dependence, resolution, stray light, and temperature dependence) will be discussed.

Journal Article↗

PubMed2003

A novel microfluidic concept for bioanalysis using freely moving beads trapped in recirculating flows.

There are only a few examples in which beads are employed for heterogeneous assays on microfluidic devices, because of the difficulties associated with packing and handling these in etched microstructures. This contribution describes a microfluidic device that allows the capture, preconcentration, and controlled manipulation of small beads (<6 microm) in etched microchannels using fluid flows only. The chips feature planar diverging and converging channel elements connected by a narrow microchannel. Creation of bi-directional liquid movement by opposing electro-osmotic and pressure-driven flows can lead to the generation of controlled recirculating flow at these elements. Small polymer beads can actually be captured in the controlled rotating flow patterns. The clusters of freely moving beads that result can be perfused sequentially with different solutions. A preliminary binding curve was determined for the reaction of streptavidin-coated beads and fluorescein-labelled biotin, demonstrating the potential of this bead-handling approach for bioanalysis.

Biotin↗

PubMed2002

Compact static Fourier transform spectrometer with a large field of view based on liquid-crystal technology.

We present designs of static Fourier transform spectrometers that are based on a Wollaston prism with a large field of view. Besides the usual advantages of static Fourier spectrometers (large resolving power, large wave-number range, high throughput), these designs also present the advantage of using relatively cheap liquid-crystal technology. The use of twisted liquid-crystal structures gives a large field of view, which in turn gives the ability to collect more light from a divergent light source. Measurements are compared with simulations. Different simulation principles are used. We found new configurations by using twisted structures that show a large field of view.

Journal Article↗