A Metal–Organic Framework as Selectivity Regulator for Fe³⁺ and Ascorbic Acid Detection

Abstract

Ferric ion (Fe3+) plays a vital role in cellular homeostasis. However, the detection of Fe3+ with rhodamine B (RhB) has potential problems, such as poor selectivity and low photostability. To address these problems, we rationally designed an RhB@MOF nanocomposite-based “on–off–on” fluorescent switching nanoprobe for highly sensitive and selective detection of Fe3+ and ascorbic acid. This RhB@MOF nanoprobe was prepared through a facile one-pot synthesis. Here MOF served as a selectivity regulator for the detection of Fe3+. By embedding RhB into the porous crystalline MOF, enhanced photostability and fluorescence lifetime of RhB to Fe3+ were achieved. The as-prepared RhB@MOF was demonstrated to be an ultrasensitive and selective nanoprobe for the detection of Fe3+ in human serum and ascorbic acid in rat brain microdialysate. Furthermore, inner filter effect (IFE) and photoinduced electron transfer (PET) were proposed and discussed to explain the selectivity and sensitivity of RhB to Fe3+ against other interfering substances. Our novel “on–off–on” nanoprobe provides insight into the rational design of MOF-based biosensors for selective and sensitive detection of analytes.

Nanoscale Metal-Organic Frameworks as Fluorescence Sensors for Food Safety

“…Over the past few years, lots of research groups tried to rapidly detect kinds of cations by the usage of NMOFs-based fluorescence sensors and have borne fruit [4]. In addition, many of them shared a similar sensing mechanism, in which NMOFs-based fluorescence sensors were selectively quenched by certain metal cations through the PET [93][94][95][96]. In this part, the latest and novel NMOFs sensors for cation detection will be introduced.…”

Hollow terbium metal–organic-framework spheres: preparation and their performance in Fe3+ detection

“…But excessive Fe 3+ will cause serious environmental issues. 14–16 Therefore, the simple, rapid and selective detection of Fe 3+ ions is meaningful to research. Due to the advantages of high sensitivity, good stability, simple operation and real-time detection, a luminescent quenching-type sensor is often considered to be an ideal choice for high-sensitivity and high-precision Fe 3+ ion detection.…”

Three Novel Zn-Based Coordination Polymers: Synthesis, Structure, and Effective Detection of Al3+ and S2− Ions

“…In recent years, coordination polymers (CPs) used as fluorescent sensors have been successfully applied in the determination of various analytes such as metal ions (Fe 3+ , Cr 2 O 4 2− , etc.) [18][19][20], small molecules (acetylacetone, water, etc.) [21,22], and explosives (TNT, PA, etc.)…”