Lysosome-targeted carbon dots for colorimetric and fluorescent dual mode detection of iron ion, in vitro and in vivo imaging

In this work, a colorimetric and fluorescent dual mode sensor based on lysosome-targeted CDs has been desirably implemented to identify Fe3+ fluctuations in vitro and in vivo. By simple one-pot hydrothermal carbonization of dried field mint, yellow-fluorescent CDs were directly fabricated without the assistance of other reagents and hold exceptional stability, superior biocompatibility as well as ultra-low cytotoxicity. Results indicated that as-prepared CDs can provide a rapid, reliable, and highly selective recognition of Fe3+ with a linear range of 0 μM–400 μM and a detection limit of 0.037 μM. Impressively, it was found that as-developed CDs can successfully target lysosome with high colocalization coefficient (0.85) and responds to fluctuations of Fe3+ in living cells. Further, acquired CDs was ingeniously devoted to Escherichia coli imaging. Besides, obtained CDs was eventually utilized to track the variation of Fe3+ in vivo system. A preliminary research expresses that as-synthesized CDs can function as an effective tool to detect Fe3+ in vitro and in vivo and thus indicates the promising applicability for disease detection in physiology and pathology in the future.