Application example: Fluorescence and Spectral Imaging for bioreader applications

 

Within the frame of research projects for investigation methods of human genome interactions and the appropriate fluorescence detection technique several laser-based fluorescence devices were developed and tested successfully in spatially- and time-resolved fluorescence measuring arrangements for dye-labelled biospots. By accommodation of the laser sources, filters and detectors (photomultiplier, CCD-array spectrometer) the requirements of different applications can be fulfilled by the following measurement schemes:

  • fluorescence intensity
  • fluorescence spectra
  • fluorescence life time (boxcar integrator, TCSPC)

As newest development the Spectral Imaging technology as a combination of an imaging spectrograph from SPECIM and an ultra-sensitive EMCCD camera from ANDOR is presented. This combination allows the simultaneous multi-colour detection of dye labelled biochips (Cy3, Cy3.5, Cy5, Cy5.5) with a strong reduction of false-positive signals of bio-spots. For the analysis of the spectral datasets multivariate data analysis techniques (unmixing) are used. We have experience with different methods of supervised and unsupervised methods.
The fluorescence detection devices were developed in a close cooperation with the Leibniz Institute for Natural Product Research and Infection Biology e.V. / Hans-Knöll-Institute (HKI).

Application example: Image-based spectroscopic sensor for the automatic control of gas burners in the glass-processing industry

The precise composition of the combustion gas mixture of burners is essential for the maximum achievable flame temperature as well as for the economic use of raw material. Therefore a mobile device for optical flame analysis and optimization of gas supply for industrial burners has been developed. The relative fuel-oxygen-ratio can be assessed by means of spectral emission in the visible and UV region by factoring in the distribution of gas emissions along the flame.
Based on spectral imaging technology the sensor allows for calculation of a flame index stating the quality of fuel supply. The flame index has been successfully determined for several fuel-oxygen-ratios.

Contact persons are This e-mail address is being protected from spam bots, you need JavaScript enabled to view it (Spectral Imaging techniques), This e-mail address is being protected from spam bots, you need JavaScript enabled to view it (applications), This e-mail address is being protected from spam bots, you need JavaScript enabled to view it (unmixing) and This e-mail address is being protected from spam bots, you need JavaScript enabled to view it (fluorescence dyes)

 

Spectral Imaging set-up for fluorescence labeled biochip detection

 

Scheme of the spectral imaging configuration consisting of the detection assembly: imaging spectrograph, camera, lens and detection filter, of the excitation assembly: laser with emission filter and line projection optics, and of the scanner assembly: biochip holder, motorized translation stage, all encased in a light-tight housing for long time detection experiments

 

Linewise excitation of spots on the biochip with 532 nm laser

 

Principle of Spectral Imaging - combination of two optical fields: conventional imaging and classical spectroscopy

 

Example of a superposed spectral signature from a threefold labeled spot excited with 532 nm, separation by unmixing into three signatures corresponding to the applied fluorescent dyes

 

The spectral imaging sensor acquires chemiluminescence and thermal emission from a row of spots along a longitudinal section through the flame.

 

From the acquired spectral dataset the concentration of single components along the flame is calculated by a spectral unmixing process. For every reaction product a concentration profile is created (right).