An Overview of the Design of Metal-Organic Frameworks-Based Fluorescent Chemosensors and Biosensors

Abstract

Taking advantage of high porosity, large surface area, tunable nanostructures and ease of functionalization, metal-organic frameworks (MOFs) have been popularly applied in different fields, including adsorption and separation, heterogeneous catalysis, drug delivery, light harvesting, and chemical/biological sensing. The abundant active sites for specific recognition and adjustable optical and electrical characteristics allow for the design of various sensing platforms with MOFs as promising candidates. In this review, we systematically introduce the recent advancements of MOFs-based fluorescent chemosensors and biosensors, mainly focusing on the sensing mechanisms and analytes, including inorganic ions, small organic molecules and biomarkers (e.g., small biomolecules, nucleic acids, proteins, enzymes, and tumor cells). This review may provide valuable references for the development of novel MOFs-based sensing platforms to meet the requirements of environment monitoring and clinical diagnosis.

Sensitive Current Sensor Based on a Lanthanide Framework with Lewis Basic Bipyridyl Sites for Cu2+ Detection

“…After adding LiOH (0.70 g, 30.0 mmol) and S2 (1.20 g, 3.00 mmol) to a mixed solution of THF (40 mL) and H 2 O (10 mL), the mixture was allowed to vigorously stir at room temperature for 24 h. After the completion of the reaction, the solid was removed via filtration, and the filtrate was concentrated under reduced pressure. The obtained residue was dissolved in water (30 mL) and acidified with 1 mol/L HCl till pH = 3 to obtain the white solid product, (6R,8R)-6,8-dimethyl-7,8-dihydro-6H- [1,5] S7), and the crystal data can be found in Table S1.…”

“…There has been increasing research attention in metal–organic frameworks (MOFs) with nanopores because of their similarity in structure and function to biological nanochannels. − In particular, the application of porous MOFs as sensing materials including pH sensors, ion sensors, gas sensors, volatile organic compound sensors, and biosensors is one of their most important applications. − In the past decade, the development of sensors, such as organic sensors, MOFs, bioengineered sensors, etc., has greatly benefited from the progress of advanced nanomaterials. − Among them, the fabrication of MOF-based sensors is simple, cheap, and easy to operate, and reliable results are always obtained using such sensors. Specific recognition of guest molecules by the porous MOFs acts as the construction standard for building functional porous MOFs to guide their functional properties and applications. , Recently, interest in applying MOFs to detect and remove heavy metals has undergone rapid growth .…”

Microcrystalline Luminescent (Eu1-xLnx)2bdc3·nH2O (Ln = La, Gd, Lu) Antenna MOFs: Effect of Dopant Content on Structure, Particle Morphology, and Luminescent Properties

“…Light-emitting materials based on the metal–organic frameworks (MOFs) of rare earth element (REE) ions have been widely discussed in recent research works because of the wide area of applications, ranging from LEDs and different sensors to bioimaging materials and medicine [ 1 , 2 , 3 , 4 ]. For practical application, the particle size of such compounds is one of the most important factors.…”

“…For practical application, the particle size of such compounds is one of the most important factors. Small-sized particles (nano- and micro-sized) have a large specific surface area, which provides high sorption properties to compounds and allows them to be used as sensor materials for heavy metal ion detection [ 3 , 5 , 6 , 7 , 8 ]. Such highly dispersed MOFs can be obtained via several synthetic approaches, namely coprecipitation [ 9 ], hydrothermal [ 10 ], solvothermal [ 11 ], sol–gel [ 12 ], magnetic-field-induced [ 13 ], and some other synthetic methods.…”

A Coordination Polymer for the Fluorescence Turn-On Sensing of Saccharin, 2-Thiazolidinethione-4-carboxylic Acid, and Periodate

“…The detection of cations, anions, biomarkers, antibiotics, amino acids, temperature, and pH value − was realized. Currently, most CP-based sensing materials have a fluorescent “turn-off” phenomenon, while fluorescent “turn-on” sensing is very rare. − Fluorescent “turn-on” sensing has strong resistance to background interference, is easier to monitor, and has a lower signal-to-noise ratio (SNR), which is more worthy of our exploration. − Based on this situation, in this paper, we have successfully synthesized a CP [Zn 2 L 2 (H 2 O) 4 ]·H 2 O ( 1 ) by selecting 1-(4-carboxyphenyl)-1 H -pyrazole-3-carboxylic acid as a single ligand (Figure S1). The ligand H 2 L has multiple open reaction sites and functional groups, which reduce the difficulty of the coordination process and are conducive to the specific recognition of analytes.…”