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arXiv · 2403.15117

Two-photon polymerization of optical microresonators for precise pH sensing

Anton V. Saetchnikov·Elina A. Tcherniavskaia·Vladimir A. Saetchnikov·Andreas Ostendorf
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Abstract

In water monitoring, environmental analysis, cell culture stability, and biomedical applications, precise pH control is demanded. Traditional methods like pH strips and meters have limitations: pH strips lack precision, while electrochemical meters, though more accurate, are fragile, prone to drift, and unsuitable for small volumes. In this paper, we propose a method for optical detection of the pH value based on the multiplexed sensor with 4D microcavities fabricated with two-photon polymerization. This approach employs pH-triggered reversible variations in microresonator geometry and integrates hundreds of dual optically coupled 4D microcavities to achieve the detection limit of 0.003 pH units. The proposed solution is a clear instance for the use-case oriented application of the two-photon polymerized structures of high optical quality. With benefits of the multiplexed imaging platform, dual 4D microresonators can be integrated alongside other microresonator types for pH-corrected biochemical studies.

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Anton V. Saetchnikov, Elina A. Tcherniavskaia, Vladimir A. Saetchnikov, Andreas Ostendorf. 2024-06-06. Two-photon polymerization of optical microresonators for precise pH sensing. https://doi.org/10.37188/lam.2024.054

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