A dual-reactivity-based surface-enhanced Raman spectroscopy nanosensor for the simultaneous imaging of hypochlorite and nitric oxide in living cells

A surface-enhanced Raman spectroscopy (SERS) nanosensor with dual-reactivity is developed for the simultaneous imaging of hypochlorite (ClO⁻) and nitric oxide (NO) in living cells. Utilizing the specific reactions between functional molecules and ClO⁻ and NO, respectively, the 2-mercapto-4-methoxy-phenol (2-MP) and o-phenylenediamine (OPD) molecules are synchronously assembled on the surface of gold nanoparticles to fabricate the dual-function nanosensors. The advantages of SERS technology, narrow peaks for spectral multiplexing and fingerprint information, further facilitate the simultaneous detection of ClO⁻ and NO. The prepared nanosensors achieve a highly sensitive and selective measurement of ClO⁻ and NO with a limit of detection of 0.054 μM and 0.46 μM, respectively. Furthermore, the SERS nanosensors enable the simultaneous visualization of ClO⁻ and NO in the single living cell, which opens up the prospects to investigate the ClO⁻- and NO-involved physiological and pathological events.