Comparative Study of Nitro‐ and Azide‐Functionalized Zn^II‐Based Coordination Polymers (CPs) as Fluorescent Turn‐On Probes for Rapid and Selective Detection of H₂S in Living Cells

Abstract

Selective detection of H2S in the cellular systems using fluorescent CPs/MOFs is of great scientific interest due to their outstanding aqueous stability, biocompatibility and real‐time detection ability. Fabrication of such materials using complete biologically essential elements and applying them as an efficient biosensor is still quite challenging. In this context, two newly synthesized CPs containing biologically essential metal ion (Zn) and nitro/azido functional groups into the framework to sense extracellular and intracellular H2S by reducing into respective amines are presented. The CP‐1 containing the azide group acted as an efficient fluorescent turn‐on probe with the lowest detection limit (7.2 μM) and shortest response time (30 s) among the Zn‐based probes reported till date. Moreover, CP‐1 exhibited green luminescence in live cells after imaging a very low concentration of H2S, whereas the nitro analogue CP‐2 could not detect the target analyte due to its framework disruption.

Enhancing the sensitivity of a water stable MOF as a H2S gas sensor by the fabrication of a mixed-matrix membrane

“…47,48 Recently, we have shown the importance of nitro and azide groups containing Zn-CPs for the detection of H 2 S by following the reductive reaction strategy. 49 Among all the three mentioned methodologies, the synthesis of a fluorescent H 2 S probe based on nucleophilic addition reaction to the olefinic double bond of MOFs is very scarce. For the realistic sensing application of MOFs as a device, it is essential to fabricate their powder forms into thin-film membranes, which is not well explored to date.…”

A turn-off–on fluorescence probe for rapid, selective and real-time detection of H2S in living cells

“…4 In this contrast, one of the evolving application of Metal Organic Frameworks (MOFs) be associated with selective and sensitive sensing of various analytes such as anions, cations, , nitro-aromatics, biological signalling molecule like H 2 S etc. 5 due to their high thermal, chemical and physicochemical stability, large porosity, tunable surface area and ability for post synthetic modification. For the first time, we adopted a smart strategy, for the synthesis of 2D Zn-MOF based fluorescence probe containing olefinic double bond conjugated with carbonyl group, which introduced us as a turn-off-on fluorescence probe for H 2 S sensing (Fig.…”