Estimation of sodium ions using easily engineered organic nanoparticles-based turn-on fluorescent sensor: Application in biological and environmental samples

Sodium balance in human body is crucial for sustaining normal physiological functions. Engineering a selective and sensitive probe for Na (I) determination is a challenging task due to the obvious interference from other alkali metal ions, particularly K (I) ions. The current study is based on the development of fluorescent organic nanoparticles (ONP) from a Biginelli-based receptor. The ONP are capable of measuring sodium concentration in the physiological range. The sensor shows adequate stability towards high ionic strength and in the pH range of 3-11. The competitive experiment reveals that the proposed sensor can selectively detect Na (I) even in the presence of possibly interfering K (I) ions. The projected sensor offers a detection limit of 22 nM which is quite impressive in comparison to other Na (I) sensors available in literature. Further, the practical applicability of the probe has been assessed through monitoring Na (I) concentration in biological (urine and sweat samples) as well as environmental (lake and tap water) samples. (C) 2018 Elsevier B.V. All rights reserved.