What’s New in Spectroscopy?

Advancing Spectral Microcombs. A new microcomb laser device could improve spectroscopic sensing, according to a new study by the University of Rochester. Despite being widely applied in spectral and optical systems, reconfigurability and decreased power efficiency remain a significant challenge to the development of microcomb lasers. And that’s why Jingwei Ling and his colleagues developed an on-chip microcomb laser with a thin-film lithium niobate (TFLN) photonic integrated circuit (PIC). This enhanced design eliminates the single wavelength that usually degrades the system’s efficiency, while also enabling a flexible mode-lock at an ultrafast speed. “We envision [our microcomb] to be of great promise for a wide range of applications including communication, optical and microwave synthesis, sensing, metrology, among many others,” concluded the authors in their paper.

Hydrogen: Algal Boom? There are a number of research groups looking into ways to produce hydrogen – a much sought-after green energy source – and spectroscopy often plays an important analytical role. For example, Wee-Jun Ong at the Xiamen University Malaysia is developing nanocatalyst-based artificial photosynthetic processes to turn water, sunlight, and carbon dioxide into clean hydrogen. And now, a team from Ruhr-University Bochum, Germany, have identified how hydrogen is produced by the unique catalytic center of some unicellular algae. Specifically, they describe the previously unexplained role of the enzyme HydF, using ATR-FTIR spectroscopy among other methods.

Biodiversity Boon. Portable Raman spectroscopy devices are opening doors in an increasing number of fields. Researchers at the Singapore-MIT Alliance for Research and Technology used a Raman leaf-clip to analyze plant diversity. The leaf clip Raman sensor consists of a Raman Fiber probe connected to a portable instrument using an 830 nm excitation laser, combined within a compact, portable instrument enclosure, which features software controls. The team achieved an overall accuracy of 91 percent for correct classification of a species within a plant group, which the authors said, “demonstrate the potential of Raman spectroscopy in contributing to plant biodiversity assessment.”  

On the CLOCK Treatments. Have you ever wondered how your gut microbiome affects your mental health? Well, that’s what prompted researchers from the University of Graz to analyze the serum and stool metabolome of major depression patients – after taking PROVIT probiotics – with nuclear magnetic resonance. Their NMR spectroscopy-based metabolomics analysis suggests an interconnection between gut bacteria and the patients’ molecular clock – affecting CLOCK gene expression, their resulting metabolites, and eventually circadian rhythm. The PROVIT-CLOCK study is the first to showcase such findings, and the authors conclude that “probiotics might be a well-tolerated add-on therapy option in individuals with MDD.”