abstract
A new phenolate-thiazole derivative (L) has been synthesized and structurally characterized. The chemo-sensing activity of L is detected by the naked eye for the aqueous carbonate anion in the pH range of 4 to 8. The selective 'turn -on' fluorescence occurs through the formation of a stable intermediate L center dot CO 3 2- (1) following the PET mechanism. The limit of detection (LOD) is found 0.18 mu M based on the absorbance -based assay. The quinonoid form of bromophenol unit binds strongly with CO 3 2- through thiazole nitrogen and hydrazinic nitrogen. Further, the selective holding of CO 3 2- anion over other planar tetranuclear anions (e.g., SO 3 2- , NO 3 - ) happens with several intra and intermolecular hydrogen bonds as envisaged by the DFT/TDFT study. The formation mechanism of L center dot CO 3 2- is proposed based on experimental and theoretical studies. The biological experiments (MTT and cell imaging) reveal the non-cytotoxicity nature of L and the biocompatible uptake of L mostly in the cytoplasm at physiological pH.
keywords
FLUORESCENT SENSORS; SOIL SAMPLES; SCHIFF-BASE; IONS; BIOMINERALIZATION; RECOGNITION; CARRIERS; DESIGN; PROBE; RED
subject category
Spectroscopy
authors
Pramanik, C; Jana, A; Brandao, P; Aher, A; Bera, P; Khatua, S; Majumdar, S; Mandal, B; Manna, SK; Bera, P
our authors
Paula Cristina Ferreira da Silva Brandão
Assistant ResearcherProjects
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
acknowledgements
We gratefully acknowledge Anirban Karak, Research Scholar, Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Howrah, West Bengal, India -711103 for the NMR and mass experiments. Paula Brandao gratefully acknowledges the financial support of this work by the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MCTES (PIDDAC) .