A Programmable Nanovesicle Platform for Megapascal Pressure Sensing

Abstract

Hydrostatic pressure (HP) is a subtle yet pervasive force that shapes chemistry and biology from the ocean floor to living cells─yet real-time HP sensing at the microscale remains elusive. Here, we report pyrene-modified polyionic complex vesicles (Pyr-PICsomes) as a class of programmable smart materials that translate HP changes into ratiometric and lifetime-modulated fluorescence. By engineering the mechanical stiffness of the vesicular membrane, we demonstrate a unique platform where material mechanics directly dictate photophysical outcomes. Specifically, we show that tuning the membrane’s elastic modulus allows for the precise control of pressure-sensitive excimer emission within the 0.1–50 MPa range. While softer membranes enhance excimer formation and signal responsiveness, stiffer architectures offer distinct lifetime modulation─enabling dual-mode sensing for both intensity-based and fluorescence lifetime imaging microscopy (FLIM) applications. This modular platform uniquely bridges mechanical design and photophysical control, unlocking a robust paradigm for probing pressure dynamics in biological, marine, and space-relevant environments.