Fluorescent molecular rotor-based polymer materials for local microviscosity mapping in microfluidic channels

Dharshana Nalatamby; Florence Gibouin; Maxime Zitouni; Julien Renaudeau; Gérald Clisson; Pierre Lidon; Simon Harrisson; Yaocihuatl Medina-Gonzalez

arXiv · 2502.13003

Fluorescent molecular rotor-based polymer materials for local microviscosity mapping in microfluidic channels

Dharshana Nalatamby·Florence Gibouin·Maxime Zitouni·Julien Renaudeau·Gérald Clisson·Pierre Lidon·Simon Harrisson·Yaocihuatl Medina-Gonzalez

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Abstract

A viscosity-sensitive monomer consisting of a methacrylate-functionalized julolidone-based molecular rotor (MECVJ) was synthesized and used to obtain viscosity-sensitive polymers (poly(DMA-\textit{s}-MECVJ)). The qualitative properties of the molecular rotor were preserved after its inclusion in the new polymer, in particular the effect of the viscosity of the surrounding medium on the fluorescence lifetime of the rotor. By grafting these polymers onto glass slides, viscosity-sensitive surfaces were obtained, showing good robustness in time after successive use and washing. As proof of concept, these surfaces were used to assemble a microfluidic chip capable of mapping viscosity of fluids flowing inside the channel.

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Dharshana Nalatamby, Florence Gibouin, Maxime Zitouni, Julien Renaudeau, Gérald Clisson, Pierre Lidon, Simon Harrisson, Yaocihuatl Medina-Gonzalez. 2025-02-18. Fluorescent molecular rotor-based polymer materials for local microviscosity mapping in microfluidic channels. https://arxiv.org/abs/2502.13003

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