Stable Cd Metal–Organic Framework as a Multiresponsive Luminescent Biosensor for Rapid, Accurate, and Recyclable Detection of Hippuric Acid, Nucleoside Phosphates, and Fe³⁺ in Urine and Serum

Abstract

Detecting biomarkers associated with diseases has significant meaning for early prevention, diagnosis, and treatment of diseases. The development of luminescent biosensors for rapid and accurate detection in real urine and serum is urgently desired for human health monitoring. Herein, a luminescent cadmium metal−organic framework, {[Cd(L)(bpbix)]•x(solv)} n (1), was successfully prepared by using a urea-functionalized dicarboxylate ligand, 5-(3-(pyridin-4-yl)ureido)isophthalic acid (H 2 L), 4,4′bis((1H-imidazol-1-yl)methyl)biphenyl (bpbix), and the Cd 2+ ion. The structure of 1 presents a 2-fold interpenetrating threedimensional pillared-layer framework. The complex 1 exhibits good stability in different-pH aqueous solutions and physiological fluids. Strikingly, the complex 1 shows quick response, high sensitivity, good anti-interference performance, and a recyclable ability for simultaneous sensing of hippuric acid (HA), nucleoside phosphates, and Fe 3+ in water. More significantly, this sensor can realize the sensitive and accurate detection of HA, nucleoside phosphates, and Fe 3+ in real urine and serum and meet the practical detection needs in clinical diagnosis. These results indicate that the complex 1 as a multiresponsive luminescent biosensor possesses great potential for practical detection of HA, nucleoside phosphates, and Fe 3+ in biological samples.

Eu(III)-Functionalized MOF-Based Dual-Emission Ratiometric Sensor Integrated with Logic Gate Operation for Efficient Detection of Hippuric Acid in Urine and Serum

“…The results show that with the introduction of Eu 3+ ions, the prepared Eu 3+ @NiMOF present higher accuracy, as well as the visible concentration-dependent discoloration trend can be observed by the naked eye under UV light. As far as we know, the LOD of Eu 3+ @NiMOF is comparable to or even superior to the already reported MOF-based HA sensors (Table ), − which illustrates it is feasible and meaningful to construct dual-emission ratiometric sensors for HA detection by encapsulating Eu 3+ ions into the confined space of MOFs through coordination interactions. It should be pointed out that the strong coordination interactions between Eu 3+ active sites and HA make the sensing recyclability worse.…”

A stable Cd-MOF as a dual-responsive luminescent biosensor for the determination of urinary diphenyl phosphate and hippuric acid as biomarkers for human triphenyl phosphate and toluene poisoning

“…S14†), according to the previous literatures. 38–40 As shown in Fig. S16,† the LUMO energy levels of DPP and HA are lower than that of 1 , which suggests that the electrons are transferred from the LUMO of 1 to the LUMOs of DPP and HA, thus leading to luminescence quenching.…”

Metal–organic frameworks (MOFs) as fluorescence sensors: principles, development and prospects

“…This sensor can serve as a powerful tool for monitoring the toluene levels in a working environment, avoiding damage to the human brain and central nervous system due to long-term exposure. 114 1-Hydroxypyrene (1-HP) is a biomarker of polycyclic aromatic hydro carbon (PAH) carcinogens. Yan et al reported a turn-off type sensor for 1-HP that can assess the concentration of PAHs in the human body by detecting the concentration of 1-HP in the urine.…”