Ratiometric Fluorescent Probe for Non-enzymatic Detection of Uric Acid and Anthrax Biomarker and Visualisation of Uric Acid

Abstract

Detection of uric acid and dipicolinic acid biomarkers are of utmost importance for early diagnosis of several critical illnesses. Lanthanide functionalised carbon dots are considered to be newly developing class of fluorescent probes with excellent potential for sensing and bioimaging of several biologically and environmentally important analytes. In this study, a novel fluorescent probe Zn-CD@Eu is synthesized using Zn-doped carbon quantum dot (Zn-CD) and ethylenediaminetetraacetate-Eu(III) (EDTA-Eu) complex. The fluorescent probe shows ratiometric fluorescence response towards dipicolinic acid (DPA) and uric acid (UA) on the basis of formation of Eu-DPA complex and charge transfer respectively. It shows relatively low limit of detections of 0.5 µM for DPA and 0.3 µM for UA. Furthermore, the fluorescent probe was successfully implemented for determining concentration of DPA and UA in human blood serum with considerable recovery rate. It is also found to have excellent stability under a variety of environmental conditions. Thus, this fluorescent probe can be employed as a tool for detection useful biomarkers in human body and considered to be suitable for real-life clinical applications.