Nanomechanical resonators as probes for living cells.

Nanomechanical resonators, including suspended microchannel resonators (SMRs), microcantilevers, doubly clamped beams, membranes, and optomechanical disk resonators, provide label-free measurements of the physical properties of single cells through changes in the sensor resonance frequency or mechanical fluctuations. These properties include cell mass, density, stiffness, viscoelasticity, refractive index, intrinsic vibrational modes, and active fluctuations. Here, we review recent advances in nanomechanical sensing of living cells, highlighting how these technologies have evolved from mass measurements toward multidimensional physical cell phenotyping. We discuss emerging capabilities such as vibrational spectroscopy, nanomotion-based functional assays, and integration with single-cell transcriptomics. Finally, we discuss current challenges and future applications for translating nanomechanical measurements into broadly practical tools for cell biology, precision medicine, anticancer drug response prediction, and antimicrobial drug susceptibility testing.