• • Yb3+/Ho3+ co-doped UCNPs exhibit spontaneous blinking with negligible photodegradation under 976 nm CW excitation, enabling prolonged SMLM without photobleaching—critical for long-term dynamic studies.
• • Kinetic analysis shows single-exponential bright-state dwell times and biexponential dark-state dwell times, indicating one decay pathway into a non-emissive state and two recovery pathways—essential for optimizing blinking kinetics.
• • In fixed cells, FRC resolution reached 30 nm, confirming sub-50 nm performance in biological specimens—meeting the resolution requirements for super-resolution imaging.
• • Live-cell imaging demonstrated synchronized transport of UCNPs with near-unity positional correlation and minimal relative velocities—enabling precise tracking of intercellular dynamics.