From cantilever dynamics to cell mechanics: advancing multimodal AFM for high-resolution biophysical investigations

Abstract

Atomic force microscopy (AFM) has emerged as a uniquely versatile platform for probing nanoscale forces, mechanical properties, and interfacial interactions across materials and biological systems1–10. However, fully exploiting its potential for quantitative biophysical and translational research requires a rigorous understanding of cantilever dynamics, optimised instrumentation, and advanced multimodal measurement strategies capable of operating under physiologically relevant conditions.

This thesis advances AFM as a multimodal, quantitative framework that bridges nanomechanical resonator physics with high-resolution cellular biomechanics and cancer-relevant mechanophenotyping. Through the integration of analytical modelling, numerical simulations, and experimental validation, new methodologies are developed to decouple mass, stiffness, and material properties in nanomechanical resonators, enabling accurate mass spectrometry and biosensing in native biological environments. The incorporation of two-dimensional material coatings and digitally guided cantilever design further enhances sensitivity, responsivity, and measurement fidelity. Building on these instrumental advances, the thesis establishes optimised strategies for dynamic and multifrequency AFM, including tailored cantilever modification, harmonic eigenmode alignment, and laser spot positioning. These developments significantly improve spatial resolution and mechanical contrast in both solid-state and biological samples.

The optimised AFM framework is then applied to quantitative studies of cellular mechanics, viscoelasticity, and adhesion across corneal epithelial, pancreatic, and prostate cell models. Multimodal AFM measurements reveal cell-type- and context-dependent mechanical phenotypes governed by cytoskeletal organization, cell-cycle state, receptor engagement, and mechanical adaptability. In particular, AFM-based microrheology exposes frequency-dependent viscoelastic signatures that differentiate normal and cancerous pancreatic cells, while receptor-targeted AFM mechanophenotyping directly links CXCR1/CXCR2 engagement to enhanced adhesion, energy dissipation, and mechanical remodelling in metastatic prostatecancer cells.

Collectively, this work positions AFM as a critical bridge between cantilever-scale physics and cellular-scale biology, providing quantitative tools for mechanobiology, nanotechnology-enabled biosensing, and cancer research. The findings establish AFM not as a single technique, but as an integrated platform capable of informing next-generation diagnostic and therapeutic strategies.

Thesis is embargoed until 30th September 2028

Date of Award	Sept 2026
Original language	English
Sponsors	Vice Chancellor's Research Scholarship (VCRS)
Supervisor	Amir Farokh Payam (Supervisor), Patrick Lemoine (Supervisor) & Patrick Lemoine (Supervisor)