One of the most popular techniques used in analytical laboratories is ultraviolet-visible spectroscopy. Since its debut in the 1940s by Cary and Beckman, UV-VIS spectroscopy has revolutionized molecular spectroscopy research. What is UV VIS spectroscopy? The intensity of light transmitted through a sample is measured compared to a reference measurement of the incident light source in UV VIS spectroscopy. Dual-beam optics, variable slit resolution, integrated electronics, and noise reduction are just a few of the advances in the optical design that have been made throughout the years.
Detectors Options
CCD array spectrophotometers have a different optical design and footprint than traditional scanning spectrophotometers. The greater number of optical surfaces required for dispersion and isolation of the appropriate wavelength before transmission through a particular sample accounts for the bigger footprint required for scanning spectrophotometers. Furthermore, scanning operations, slit selection, and beam splitting require a large number of moving parts.
Sources of light
A quartz tungsten lamp is used for visible wavelengths between 350 and 1000 nm, whereas deuterium lamps are employed for UV wavelengths below 350 nm in UV-VIS spectroscopy. Xenon lamps have been utilized in lower-cost systems, but they lack the light output, stability, and flexibility of specialized deuterium and tungsten sources. Users should opt for units with distinct, dedicated light sources when choosing an instrument, regardless of scanning or CCD array types, for the best performance.
Fiber optics
Many detractors mentioned solarization of optical fibers and photo-oxidation of samples as potential flaws of array spectrographs when fiber-optic capable devices were initially developed. Both of these misconceptions were rapidly debunked, as solarization-resistant fibers are often utilized and sample analysis periods are too short for photo-oxidation to occur. Furthermore, in high-quality optical systems with optical shutters, these effects are virtually minimized.
Sampling options
The contemporary UV-VIS system has an almost infinite number of uses. The diversity of the different fiber-optic sampling attachments allows for new applications to be identified and deployed regularly. Traditional UV-VIS spectroscopy, for example, was limited to liquid matrices using standard 1-cm cuvettes. Thanks to today’s flexible fiber-optic technology, a new generation of UV-VIS spectroscopists have been introduced to UV-VIS spectroscopy. Rather than classic cuvettes, dip probes now account for more than half of all units sold.
Software
Software flexibility is an inherent benefit of CCD array spectrophotometers. Because the complete spectrum is instantly available and saved in memory, this data can be analyzed in various ways. Typical features include peak location, quantisation, multiple spectrum overlay, and timed acquisition.
Conclusion
The CCD array of today’s spectrophotometer is the culmination of classical UV-VIS spectroscopy’s technological evolution. These systems are more adaptable, dependable, and compact than they have ever been. Furthermore, the versatility provided by fiber optics and CCD sensing has made UV-VIS spectroscopy accessible to a new generation of users and applications. New systems with Peltier-cooled CCDs for better fluorescence applications and dual-beam designs will undoubtedly follow. Hope you’ve perfectly understood what is UV VIS spectroscopy.