Related Experiment Video
Updated: Jan 11, 2026
![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
2-Hydroxy-5-ethylphenylphosphonic acid and its application in carbon dot modification: synthesis, protonation,
Jiaxin Dong1, Galina S Tsebrikova2, Yuliana I Rogacheva3
1Institute for Advanced Ceramics, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150001, PR China. libq@hit.edu.cn.
Abstract:
In this work, we optimized the synthesis of 2-hydroxy-5-ethylphenylphosphonic acid (HEPPA) and synthesized carbon dots (CDs) modified with HEPPA (CDsHEPPA) for the recognition of metal ions. HEPPA was synthesized by 1,3-phosphate-phosphonate rearrangement of diethylphenylphosphates with subsequent hydrolysis of trimethylsilyl esters. The functional groups of CDsHEPPA were characterized using protonation constants and 31P NMR and IR spectra, which were compared with the spectra of HEPPA. The stability constants of HEPPA complexes with metal ions in water were determined and compared with the fluorescence properties of CDsHEPPA in the presence of metal ions. The specific recognition of copper(II) ions by CDsHEPPA was achieved using fluorescence quenching. Biological properties such as cytotoxicity and accumulation in HeLa cells were studied for both HEPPA and CDsHEPPA. CDsHEPPA showed lower cytotoxicity compared to HEPPA and the Cu2+-HEPPA complex. CDsHEPPA penetrated into cells and then diffusely distributed in the cytoplasm and perinuclear space. Incubation with copper(II) ions led to a decrease in the fluorescence intensity of CDsHEPPA in HeLa cells.
More Related Videos
Related Concept Videos
Extraction: Advanced Methods
Photoluminescence: Applications
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...

