Speaker
Description
Microfluidics focuses on the manipulation of fluids at the micrometer scale, enabling precise flow control, transport, and reaction conditions. This technology has gained increasing importance in biomedical and bioanalytical research, leading to microfluidic systems capable of reproducing physiologically relevant flow and transport phenomena in cellular microenvironments [1] or efficient cell and microparticle separation [2]. In chemical research, diffusion‑dominated mixing in microfluidic reactors enables highly controlled reactions, improving yields, selectivity, and safety, particularly for hazardous processes [3].
In catalytic chemistry, an emerging and rapidly evolving field is polariton chemistry, which introduces new opportunities for controlling chemical reactivity through light-matter interactions [4].
Polariton chemistry relies on the strong coupling between molecular vibrational or electronic transitions and the electromagnetic modes of an optical cavity, leading to the formation of hybrid light-matter states known as polaritons, which can alter potential energy surfaces and modify reaction pathways [5].
Recent studies have demonstrated that energetic coupling between vibrational levels of reactants and an optical cavity, known as vibrational strong coupling (VSC), can accelerate reaction rates, suppress competing pathways, or enhance selectivity toward specific products in ways considered unconventional within the framework of classical catalysis. These effects are particularly attractive when combined with microfluidic environments, where confinement, precise flow control, and efficient heat and mass transfer already play a critical role. The integration of polariton chemistry with microfluidic systems thus opens new avenues for reaction control, enabling non‑thermal and non‑chemical strategies to steer catalytic processes toward desired outcomes [6].
In this context, we present the potential and challenges of this research field by investigating ester deprotection reactions under VSC in Fabry–Pérot microfluidic cavities, monitored via product absorption in the UV–Vis spectral range. We introduce an analytically sound method for extracting reliable kinetic information from absorption spectra, specifically designed to mitigate errors caused by cavity interference fringes. The method allows for tracking and correcting kinetic data for cavity relaxation processes during the reaction and provides rigorous guidelines for VSC characterization, including extraction of the true, loss-corrected Rabi splitting, confirming its expected dependence on the square root of the concentration. By applying rigorous data processing based on pseudo-first- or second-order kinetic equations, a marked improvement in the rate constant was observed. This established methodology provides a reliable analytical tool essential for future spectroscopic investigations of VSC, adaptable to other reactions and operating conditions.
References
[1]. S.N. Bhatia et al. Nature Biotechnology 2014, 32, 760–772.
[2]. M.S. Khan et al. Lab on a Chip 2025/26, https://doi.org/10.1039/D5LC00826C.
[3]. R.L. Hartman et al. Angew. Chem. Int. Ed. 2011, 50, 7502–7519.
[4]. J. George et al. ACS Catal. 2023, 13, 2631-2636.
[5]. A. D. Dunkelberger et al. Annu. Rev. Phys. Chem. 2022, 73, 429-51.
[6]. B. Xiang et al. Chemical Reviews, 2024, 124, 2512–2552.