Highly selective and sensitive fluorescence sensing of nanomolar Zn2+ ions in aqueous medium using Calix[4]arene passivated Carbon Quantum Dots based on fluorescence enhancement: Real-time monitoring and intracellular investigation.

Highly selective and sensitive fluorescence sensing of nanomolar Zn2+ ions in aqueous medium using Calix[4]arene passivated Carbon Quantum Dots based on fluorescence enhancement: Real-time monitoring and intracellular investigation. Anal Chim Acta. 2018 Jun 07;1009:1-11 Authors: Kaur H, Raj P, Sharma H, Verma M, Singh N, Kaur N Abstract Carbon Quantum Dots (CDs) owing to its unique photophysical properties have attracted immense consideration of the researchers in last decade to explore its applications in the fields of bio-imaging and sensing. In the present work, we have developed a novel CDs functionalized with Calix[4]arene derivative by hydrothermal route to detect biologically pertinent Zn2+ ions. Surface modification of CDs enhances fluorescence efficiency apart from introducing active surface sites broadening its sensor capabilities. The obtained surface-functionalized CDs exhibits a strong blue fluorescence under UV light (365 nm) with a quantum yield (Φ) of 56% which is appreciably good. Zn2+ ions get apprehended in the cavity formed due to passivation by Calix[4]arene moeity on the exterior of CDs having profuse -NH2 groups. Addition of Zn2+ ions into the solution of CDs results in remarkable enhancement in the fluorescence intensity attributed to Photo-induced Electron Transfer (PET) "OFF" phenomenon. The CDs based nanosensor exhibited a wide linear response with a detection limit of 7.34 nM. Significantly, CDs were ...
Source: Analytica Chimica Acta - Category: Chemistry Authors: Tags: Anal Chim Acta Source Type: research