Multi-action of a Fluorophore in the Sight of Light: Release of NO, Emergence of FONs, and Organelle Switching

• Published in: ACS applied materials & interfaces Vol. 14; no. 50; pp. 55957 - 55970
• Main Authors: Chakraborty, Barsha, Biswas, Suprakash, Pramanik, Anup, Koner, Apurba Lal
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 21-12-2022
• Subjects: Fluorescent Dyes; Functional Nanostructured Materials (including low-D carbon); Lipid Droplets; Nanoparticles; Nitric Oxide; Nitrogen Dioxide; fluorescent organic nanoparticles; red-edge excitation shift; naphthalimide dyes; cellular imaging; organelle switching; nitric oxide release
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.2c16693

Light, as an external stimulus, has begun to engage a phenomenal role in the diverse field of science. Encouraged by recent progress from biology to materials chemistry, various light-responsive fluorescent probes have been developed. Herein, we present a 1,8-naphthalimide-based probe NIT-NO 2 capable of releasing nitric oxide (NO) along with the formation of fluorescent organic nanoparticles (FONs) upon exposure to near-visible UV light. By synthesizing the photoproduct NIT-OH, we unveiled that initially NIT-NO 2 released NO and converted to NIT-OH, while prolonged irradiation led to the formation of FONs that is corroborated by the red-edge excitation shift as well as microscopic investigation. Finally, we have successfully applied NIT-NO 2 and NIT-OH for specific labeling of lipid droplets and plasma membranes, respectively, and demonstrated the switching from lipid droplets to plasma membranes by using light as a stimulus. These two probes show unique imaging applications inside the cells depending on the polarity and hydrophobicity of the environment. This work paves a fascinating way for the generation of excitation-dependent FONs from a small organic fluorophore and highlights its potency as an exclusive imaging tool.