Smart intercalation and coordination strategy to construct stable ratiometric fluorescence nanoprobes for the detection of anthrax biomarker

Abstract

In this work, two novel fluorescent nanoprobes for detecting the anthrax biomarker 2, 6-dipicolinic acid (DPA) has been developed based on well-designed anionic sulphonated naphthalene derivative (L) intercalating and coordinating...

Two Octa-Nuclear {Ln8} (Ln = Tb, Dy) Complexes with “4 + 4” Covalent Organic Macrocycles: Structure, Solution Behavior, Luminescence, and Magnetic Properties

“…To further explore the detection selectivity of Tb 8 L 4+4 to DPA, we investigated its sensing behavior in response to potential interferents, such as aromatic carboxylates (PA, DF, BTC, INA, BA, NA, IPA, and TPA), amino acids (Gly, Phe, and Asp), and ions (Na + , K + , Mg 2+ , Ca 2+ , Cl – , NO 3 – , and CO 3 2– ) (Figure S6), which were abundant in numerous bacterial spores. ,− When the above substances with different concentrations (0–50 μM) were added to Tb 8 L 4+4 (10 μM), only DPA significantly enhanced the fluorescence intensity. Meanwhile, when interfering substances were mixed with DPA in Tb 8 L 4+4 aqueous solution, only DPA could significantly enhance the fluorescence intensity of it, even in a higher concentration of potentially interfering substances (Figures b inset and S7).…”

Polyarylether-based COFs coordinated by Tb3+ for the fluorescent detection of anthrax-biomarker dipicolinic acid

“…Scheme 2 describes a typical process of sensitizing the characteristic luminescence of lanthanide ions by coordination. [39][40][41] The excited DPA of the completed coordination is transformed into the excited triplet state by intersystem crossing, and then the energy is transferred to Tb 3+ , Tb 3+ is excited quickly from the ground state to the excited state and then emits strong characteristic fluorescence. 42,43 To corroborate the above mechanism, density functional theory (DFT) calculations were performed for JUC-505 and DPA as shown in Scheme 2b and c. Compared to other atoms, the carboxyl oxygen atom exhibits significant negative charge distribution, indicating its ability to adsorb and coordinate with Tb 3+ .…”

Dual emission and its λ-ratiometric detection in analytical fluorimetry Pt. II. Exploration in sensing and imaging

“…Among them are the λ-ratiometric sensors for viscosity [139], temperature [140] and pressure [141] on a molecular scale. Detection of pathogenic bacteria [142], checking their drug resistance [143] and identifying the spores [144] benefit from using ratiometric fluorescence sensing. Viruses, including SARS-CoV-2, can be detected by λ-ratiometric visualization [145] or by two-color immunoassays [146].…”