Startups.

Low-interference Raman spectroscopy

“Molecules are quantum mechanical oscillators. The selectivity or the ability to identify chemicals of the vibrational spectrum is based on the fact that each molecule has its characteristics spectrum, fingerprint, defined by the geometry, atomic masses and the bonds. Thus the vibrational spectrum of a molecule is an “universal” constant – for example H2O, CH4 etc. spectra are identical on Earth and in a distant galaxy. The intensity (photons (/sec  / spectral element) is the basis for the quantitative analysis, (g/liter of target analyte the sample contains). Analytical applications of vibrational spectroscopy had already a major role World War 2 engine fuel development – the vibrational spectra were collected with (slow, noisy and bulky) prism  Mid Infrared (MIR) monochromators. Since the absorption coefficients are high at MIR, the sampling is “painful and difficult”. Starting from 1970,  the demand for online process, low cost and portable instrumentation instrumentation resulted Near InfraRed (NIR) analysers which provide easy sampling and potential for use of fiberoptic probes allowing the physical separation of the instrument from the process. However, the information that NIR can provide is very restricted compared to MIR spectroscopy. Starting from 1990, Raman spectroscopy started to enter to the analytical instrumentation markets. Raman is an inelastic scattering process of photons from the molecules of the studied samples. Raman combines the high information content, of MIR, easy sample handling and potential for fiber optic sampling of NIR. In recent years, Raman has entered also to portable markets and the growth is high. Present applications of Raman include analytical laboratories, pharmaceutical industry material identification and quality control, military, homeland security, forensics, bioprocess monitoring, anything where we want to identify or measure concentrations of chemicals and the need for this ability is huge. The largest obstacle for the explosion of the Raman instrument markets, is the fact that Raman emission, being a weak phenomenon, is easily masked by fluorescent photons emitting from the sample when probed with the excitation laser. The fluorescence is a prohibiting problem in 90 % of the otherwise potential Raman applications. Our technology suppresses the fluorescence with a combination of a pulsed laser excitation and time gated detection, based on the fact that Raman response time is below 1 picoseconds whereas typical fluorescence lifetimes are few thousand picoseconds. The technology has potential to be applied in microscopy, process- and portable instruments”