Biomedical Applications Using Raman Systems
Interested in how Raman systems can be used in biomedical applications?
While Raman spectroscopy has long been useful in pharmaceutical analysis and the identification of hazardous materials, the technology’s usefulness in biomedicine has also been expanding due to less bulky, miniaturized instrumentation. Its inherent capability to distinguish molecular composition is being integrated into specialized diagnostics, in applications such as endoscopy, cancer detection, bone density, and additional in vivo and in vitro biomedical systems.
Historically, practitioners of Raman spectroscopy have struggled with the elusive nature of Raman scattered “signal” photons from within the Rayleigh scattered source background. Fewer than one in a million photons exchange vibrational energy with the molecules under test and exhibit the associated Raman wavelength shift. To extract this Raman signal from the background, highly wavelength-selective optical filters are necessary to provide more signal with less background to the detectors to enable the visibility of molecularly unique Raman fingerprint characteristics.
The adaptation of filters has become even more important as the instrumentation has grown smaller. In many cases, these point-of-use portable laboratories and in vivo diagnostic setups have required filters with functionality similar to their benchtop predecessors. The need still exists to clean up the excitation source (laser line filters), to selectively direct the excitation and Stokes scattered light (dichroic mirrors), and to isolate the Raman signal from the excitation background (edge-pass or notch filters). However, in contrast to lab instruments for scientific analysis, portable analytical instruments typically require less precision, because the analysis involves comparing an acquired spectrum to a library database of expected possible spectra. The identification is based on the closest match that is found.
Check out Iridian’s article, “Optical Filters Narrow the Focus of Raman Biomedical Analysis,” discussing this topic and the critical role optical filters play in these systems.
To request more information or a quotation for Iridian products, contact IL Photonics.