A Water-Stable Luminescent Metal–Organic Framework for Rapid and Visible Sensing of Organophosphorus Pesticides

Abstract

Metal–organic frameworks (MOFs) have shown considerable prospects for sensing pesticide residues. However, the low stability of MOFs in water hinders them from testing food and environmental samples. Herein, we report an easy and cost-efficient synthesis of a water-stable zirconium luminescent MOF (Zr-LMOF) and its application for rapid, sensitive, and in situ detection of organophosphorous pesticides (OPPs). The Zr-MOF is prepared using Zr­(IV) and 1,2,4,5-tetrakis­(4-carboxyphenyl)­benzene. The synthesized Zr-LMOF rapidly absorbs trace amounts of OPP parathion-methyl and indicates its presence. A low limit of detection of 0.115 μg kg–1 (0.438 nM) with a wide linear range from 70 μg kg–1 to 5.0 mg kg–1 was achieved. Satisfactory recoveries ranging from 78% to 107% were obtained for spiked food and environmental samples. Further, the Zr-LMOF was applied to imitate rapid and in situ imaging detection of pesticide residue on fresh produce nondestructively; visual signals appeared under ultraviolet light within 5 min. These results suggest that the Zr-LMOF has the potential for low-cost, rapid, and in situ imaging detection of OPPs contamination via easy-to-read visual signal.

RhB‐Embedded Zirconium–Naphthalene‐Based Metal–Organic Framework Composite as a Luminescent Self‐Calibrating Platform for the Selective Detection of Inorganic Ions

“…In addition, the red emission of the composites from R@D1 to R@D3 occurred with ap artial redshift (from 595 to 607 nm), which may be due to the enhanced interactions between RhB molecules with the increasing loading quantity.A ss hown in Figure 2b,a significant spectralo verlap between thea bsorption of RhB and emission of DUT-52 is observed, which illustrates the occurrence of resonance energy transfer from DUT-52 to RhB. [35][36][37] To further confirm this case, the fluorescence lifetime of the RhB@DUT-52 composites and RhB was measured by monitoring their individual red emission peaks ( Figure 2c). The lifetime is 11.60, 5.16, and 2.01 ns for the R@D1, R@D2, and R@D3 composites, respectively,w hereas this value is 1.43 ns for RhB in aqueous solution.T he longerl ifetimef or the RhB@DUT-52 composites further demonstratest he existence of resonance energy transfer from DUT-52 to RhB.…”

“…Notably,R hB in the solid state is nearly nonfluorescent due to an aggregation-induced quenching effect, and its solution shows concentration-dependent fluorescence( FiguresS6a nd S7, Supporting Information). [35][36][37] To further confirm this case, the fluorescence lifetime of the RhB@DUT-52 composites and RhB was measured by monitoring their individual red emission peaks (Figure 2c). With increasing encapsulation quantity of RhB, the peak-to-heightr atio of the two emissions changed continuously,i nw hich the intensity of the blue emission is weakeneda nd the red emission is strengthened.…”

“…In addition, the red emission of the composites from R@D1 to R@D3 occurred with a partial redshift (from 595 to 607 nm), which may be due to the enhanced interactions between RhB molecules with the increasing loading quantity. As shown in Figure b, a significant spectral overlap between the absorption of RhB and emission of DUT‐52 is observed, which illustrates the occurrence of resonance energy transfer from DUT‐52 to RhB . To further confirm this case, the fluorescence lifetime of the RhB@DUT‐52 composites and RhB was measured by monitoring their individual red emission peaks (Figure c).…”

Metal–Organic Frameworks Based on Group 3 and 4 Metals

“…Zhou and co-workers also reported a series of tetratopic ligands with different symmetries and Zr-MOFs with flu (PCN-605 or UMCM-312), scu (PCN-606), and csq (PCN-608) topologies were formed. [206][207][208] In past two years, lots of Zr-MOFs with the abovementioned topologies have been documented, including ftw (Zr-bptc, [209] Zr-IAM-4, [210] and Zr-PdX [211] ), csq (BUT-17, [212] MIP-200, [213] and NU-100x, x = 3, 4, 5, 6, 7, [214] 8 [215] ), scu (Zr-TTFTB, [216] PCN-901-SO 2 , [217,218] LIFM-114, [219] BUT-62, [220] BUT-63, [220] BUT-74, [221] Zr-abtc, [209] Zr-LMOF [222] and UU-100 [223] ), she (Zr-Me-TTFTB [216] ), sqc (MFM-601 [224] or BUT-15, [225] BUT-72, [221] and BUT-73 [221] ), and flu (PCN-902-O [217] ). The spirobifluorenelinkerbased ftw MOF Zr-IAM-4 is a twofold interpenetrated s tructure, which is different from PCN-221.…”

“…[212] The robust 2D Zr-MOF built on the V-shaped dicarboxylate linkers reported by Li and co-workers exhibits remarkably high sensitivity toward acetone vapors. [188] The scu Zr-LMOF also shows rapid, sensitive and in situ detection of organophosphorous pesticides (OPPs) with a low detection limit of 0.438 × 10 −9 m. [222] A "turn-on" fluorescent sensor has been recently assembled by combining an anthracene-based fluorophore and a hemicyanine-containing cyanide responsive recognition moiety within a complex cavity of PCN-700, reported by Zhou and co-workers. [251] The optimized MOF sensor exhibits very good performance for the detection of CN − with a low detection limit of 0.5 × 10 −6 m. Similarly, multicomponent UiO-68-An/Ma also shows good fluorescent turn-on sensing properties for biothiols at a low concentration of 50 μmol L −1 within 5 min.…”