Efficient Eu³⁺-Integrated UiO-66 Probe for Ratiometric Fluorescence Sensing of Styrene and Cyclohexanone

Abstract

The development of probes with sensitive and prompt detection of volatile organic compounds (VOCs) is of great importance for protecting human health and public security. Herein, we successfully prepared a series of bimetallic lanthanide metal–organic framework (Eu/Zr-UiO-66) by incorporating Eu3+ for fluorescence sensing of VOCs (especially styrene and cyclohexanone) using a one-pot method. Based on the multiple fluorescence signal responses of Eu/Zr-UiO-66 toward styrene and cyclohexanone, a ratiometric fluorescence probe using (I 617/I 320) and (I 617/I 330) as output signals was developed to recognize styrene and cyclohexanone, respectively. Benefitting from the multiple fluorescence response, the limits of detection (LODs) of Eu/Zr–UiO-66 (1:9) for styrene and cyclohexanone were 1.5 and 2.5 ppm, respectively. These are among the lowest reported levels for MOF-based sensors, and this is the first known material for fluorescence sensing of cyclohexanone. Fluorescence quenching by styrene was mainly owing to the large electronegativity of styrene and fluorescence resonance energy transfer (FRET). However, FRET was accounted for fluorescence quenching by cyclohexanone. Moreover, Eu/Zr–UiO-66 (1:9) exhibited good anti-interference ability and recycling performance for styrene and cyclohexanone. More importantly, the visual recognition of styrene and EB vapor can be directly realized with the naked eyes using Eu/Zr–UiO-66 (1:9) test strips. This strategy provides a sensitive, selective, and reliable method for the visual sensing of styrene and cyclohexanone.

Self-aspiration sampling design for rapid analyses of volatile organic compounds based on atmospheric pressure chemical ionization/photoionization combined ionization source mass spectrometry

“…BTEX and cyclohexanone are ubiquitous gaseous pollutants in the environment and are linked to various diseases. 40,41 Therefore, developing a rapid detection strategy for BTEX and cyclohexanone is needed. Four typical volatile compounds (toluene, cyclohexanone, styrene, and ethylbenzene) were used as research objects.…”

Fabrication of a Terbium-Functionalized Cadmium Organic Framework with Proper Energy Levels as a Ratiometric Probe of an Anthrax Biomarker

“…Currently, most MOF-type fluorescence sensors still operate based on single-band mode and are susceptible to external factors such as environmental and machine interference. In comparison, the ratiometric-type fluorescent probe can effectively eliminate external interference and demonstrate superior repeatability and reliability. − Currently, there are three main types of ratiometric fluorescent sensors . First, heterometallic MOF materials, such as introducing both Eu and Tb simultaneously.…”

Selective and Rapid Detection of 4-Nitrophenol in River and Treated Industrial Wastewater by a Luminescent Lanthanide Metal–Organic Framework Sensor

“…Metal–organic frameworks (MOFs) are crystalline porous materials composed of metal ions/clusters and organic linkers, which have been extensively applied in the detection of cations, − anions, biomarkers, − and small organic molecules. , MOFs have been explored for 4-NP detection via their fluorescence sensing mechanisms and have shown excellent detection capabilities. − For example, Wang et al studied the trace detection of a range of nitrophenol compounds in DMF solution with Tb-MOF, reporting a sensitivity of 2.25 × 10 4 M –1 and a limit of detection (LOD) of 1.12 × 10 –6 M for 4-NP . In addition, Guo et al reported that Eu-MOF emitted bright red luminescence and could function as a luminescent sensor for 4-NP in aqueous media with high sensitivity, selectivity, and a low detection limit .…”