resumo
Two simple probes, derived by condensation of ethylenediamine with 3-ethoxysalicylaldehyde (L) and salicylaldehyde (L1) have been exploited for selective recognition of Zn2+. The interaction between probes and Zn2+ has been established by spectroscopic techniques and confirmed by single crystal X-ray structures of the resulting Zn2+ complexes. It is proposed that Zn2+ inhibits the PET process, originally responsible for non-emissive nature of free ligand and turns the fluorescence ON through CHEF process. The L and L1 probes respectively detect as low as 1.8 nM and 1.16 nM Zn2+, while corresponding binding constants are 2.9 x 10(6) M-1 and 4.57 x 10(5) M-1. L1 is very effective for intra-celullar imaging of Zn2+ in HeLa and MDA-MB-468 cells. The density functional theoretical studies unveil the energy parameters involved in the probe-Zn2+ interaction process.
palavras-chave
PHOTOINDUCED ELECTRON-TRANSFER; TURN-ON; FLUORESCENT SENSOR; SCHIFF-BASE; SELECTIVE DETECTION; ZINC SENSOR; IONS; CHEMOSENSOR; PET; RELEASE
categoria
Chemistry
autores
Mahiuddin, M; Banerjee, M; Shaikh, A; Shyam, T; Taniya, S; Ghosh, A; Adhikary, A; Brandao, P; Felix, V; Das, D
nossos autores
Paula Cristina Ferreira da Silva Brandão
Investigador Auxiliar
Vítor Félix
Professor Associado com Agregaçãoagradecimentos
We are grateful to UGC (New Delhi, India) for financial support. We acknowledge Dr. S. Karmakar, USIC, BU for extending the facility of single crystal X-ray diffractometer. The crystal data of M1 and M2 were obtained using the X-ray diffraction facility of CICECO - Aveiro Institute of Materials (project UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement.