Spatial Polarization-Induced Fluorescence Fluctuation Imaging (SPIFFI) Enables Single-shot Super-Resolution and Multidimensional Imaging

Fluorescence super-resolution microscopy has advanced optical imaging into the nanoscale regime, transforming biological and interdisciplinary research. However, conventional wide-field super-resolution techniques often compromise temporal resolution, thereby limiting the ability to capture rapid and transient biological events in living systems. Here, we introduce spatial polarization-induced fluorescence fluctuation imaging (SPIFFI), a multi-channel polarimetric method that enables single-shot super-resolution imaging and six-dimensional information extraction. By leveraging the inherently smaller point spread function (PSF) under polarized detection and capturing polarization-dependent spatial fluctuations across multiplexed channels, SPIFFI achieves instant resolution enhancement from a single exposure. This capability substantially enhances the feasibility of volumetric live-cell super-resolution imaging. Moreover, SPIFFI images can be seamlessly integrated with existing fluctuation-based methods for further post-processing and resolution improvement. We demonstrate the versatility of SPIFFI through experiments on both fixed and live cells, capturing rapid subcellular dynamics and enabling high-throughput, multidimensional imaging beyond the diffraction limit. SPIFFI thus offers a practical and robust platform for real-time super-resolution imaging in biological research.