Single Gold@Silver Nanoprobes for Real-Time Tracing the Entire Autophagy Process at Single-Cell Level

This article describes a multimodified coreshell gold@silver nanoprobe for real-time monitoring the entire autophagy process at single-cell level. Autophagy is vital for understanding the mechanisms of human pathologies, developing novel drugs, and exploring approaches for autophagy controlling. A major challenge for autophagy study lies in real-time monitoring. One solution might come from real-time detection of in situ superoxide radicals (O-2(center dot-)), because it is the main regulator of autophagy. In this work, our proposed nanoprobes were etched by O-2(center dot-) and gave a notable wavelength change in the plasmon resonance scattering spectra. Both the experimental and simulated results suggested the wavelength change rate correlated well with O-2(center dot-) level. This response enabled its application in real-time in situ quantification of O-2(center dot-) during autophagy course. More importantly, with the introduction of relay probe operation, two types of O-2(center dot-) regulating autophagy processes were successfully traced from the beginning to the end, and the possible mechanism was also proposed.