N-isopropylacrylamide and spiropyran copolymer-grafted fluorescent carbon nanoparticles with dual responses to light and temperature stimuli


The fluorescent nanocomposites of carbon nanoparticles grafted with N-isopropylacrylamide and spiropyran copolymers (f-CNP-g-poly(NIPAM-co-SP)) were successfully synthesized via reversible addition-fragmentation chain transfer polymerization. The synthesized f-CNP-g-poly(NIPAM-co-SP) nanocomposites could be well dissolved in water and retain the fluorescence of carbon nanoparticles, which could simultaneously fluoresce blue-green and red. The blue-green and red fluorescence of the f-CNP-g-poly(NIPAM-co-SP) nanocomposites dissolved in water could be reversibly switched under UV and visible light stimuli. When the temperature increased from room temperature (20 °C) to 38 °C, the blue-green fluorescence intensity decreased, the red fluorescence intensity increased, and the average hydrodynamic diameter of the f-CNP-g-poly(NIPAM-co-SP) nanocomposites increased due to aggregation.

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We gratefully acknowledge the financial support from the National Natural Science Foundation of China (project nos. 21776218, 51778266, and 81701837), the Natural Science Foundation of Hunan Province (project no. 2020JJ4303) and the Open Fund of the Beijing Key Laboratory for Optical Materials and Photonic Devices.

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Correspondence to Bo Liao or Benqiao He.

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Liao, B., Liu, X., Liao, S. et al. N-isopropylacrylamide and spiropyran copolymer-grafted fluorescent carbon nanoparticles with dual responses to light and temperature stimuli. Polym J 52, 1289–1298 (2020). https://doi.org/10.1038/s41428-020-0383-0

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