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We described here two plasmonic-based nanoprobes with purpose of imaging dynamic biologic process of single tumor cells. At first, we proposed a multi-modified core-shell gold@silver nanorods 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. The plasmon resonance scattering spectra of the nanoprobes was superoxide radicals (O2•-)-dependent, a major indicator of cell autophagy, and suitable for real-time monitoring at single-cell level. More importantly, with the introduction of ‘relay probe’ operation, two types of O2•--regulating autophagy processes were successfully traced from the beginning to the end, and the possible mechanism was also proposed. According to our results, intracellular O2•- level controlled the autophagy process by mediating the autolysosome generation. Different starvation approaches can induce different autophagy processes, such as diverse steady state time-consuming. In addition, a plasmonic-based nanothermometer was prepared via dense thermosensitive polymer (pNIPAAm) capping on gold nanorods, of which the plasmon resonance spectra was linearly dependent on adjacent temperature. In this work, the white light transmitted dark-field illuminator was replaced by a laser total internal reflection dark-field microscope (LTIR-DFM) system in order to overcome the low-throughput and inexorable biological scattering background of DFM, as well as interference from mechanic noise, nanoprobe direction, optical system drift, etc. With this nanothermometer, we have successfully captured temporal biological thermal process (thermogenesis) occurred in single tumor cells, providing a new potential strategy for in-situ cellular analysis.
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