20.500.12556/RUL-180874 Nanometer-precision tracking of adipocyte dynamics via single lipid droplet whispering-gallery optical resonances Biophotonics─and more recently, biointegrated photonics─offer transformative tools for probing cellular processes with unprecedented precision. Among these, whispering-gallery-mode (WGM) resonators (optical microcavities formed in spherical structures) have emerged as powerful biosensors and intracellular barcodes. Lipid droplets (LDs), with their high refractive index and intrinsic spherical geometry, are ideal candidates for supporting intracellular lasing. Although lasing in LDs has been previously demonstrated, it has not yet been harnessed to study live-cell biology. Here, we report the first use of WGM resonances in LDs of live primary adipocytes, employing a continuous-wave (CW) laser at powers below the biological damage threshold. By measuring these resonances, we achieved nanometer-scale precision in size estimation, enabling real-time observation of rapid LD dynamics and deformations on the minute scale─far beyond the spatiotemporal resolution of conventional microscopy. We systematically characterized this photonic sensing approach, demonstrating its ability to resolve adipocyte heterogeneity, monitor lipolytic responses to forskolin and isoproterenol, and detect early signs of cell viability loss─well before conventional assays. This proof-of-concept establishes intracellular LD WGM resonances as a robust platform for investigating live single-cell metabolism. The technique enables rapid, cost-effective assessment of adipocyte function, reveals cell-to-cell variability obscured by bulk assays, and lays the foundation for high-throughput analysis of metabolism- and obesity-related diseases at both the cellular and tissue levels. adipocyte dynamics lipid droplets whispering gallery modes optical resonances lipolysis lasers lipids liquids physical and chemical properties dinamika adipocitov lipidi kapljice true false true Angleški jezik Slovenski jezik Članek v reviji 2026-03-18 14:11:24 2026-03-18 14:11:34 2026-03-21 04:01:51 0000-00-00 00:00:00 2026 0 0 Str. 511-521 iss. 1 Vol. 11 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 577 2379-3694 10.1021/acssensors.5c03272 271613187 nanometer-precision-tracking-of-adipocyte-dynamics-via-single-lipid-droplet-whispering-gallery-optical-resonances.pdf nanometer-precision-tracking-of-adipocyte-dynamics-via-single-lipid-droplet-whispering-gallery-optical-resonances.pdf 1 BBBD1BBD8826D1CA20FB51DBE363A038 f74f822af16f4e1d8b79f8ba6e85b76006b5de1cd7c79c2b94c3d1e58d8ca5b8 8dd4b668-22cc-11f1-b0ab-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=230810 https://pubs.acs.org/doi/10.1021/acssensors.5c03272 1 ea242bea-22cb-11f1-b0ab-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=230809 Fakulteta za matematiko in fiziko 0 0 0