Highly Luminescent MOF and Its In Situ Fabricated Sustainable Corn Starch Gel Composite as a Fluoro-Switchable Reversible Sensor Triggered by Antibiotics and Oxo-Anions

Abstract

Frequent use of antibiotics and the growth of industry lead to the pollution of several natural resources which is one of the major consequences for fatality to human health. Exploration of smart sensing materials is highly anticipated for ultrasensitive detection of those hazardous organics. The robust porous hydrogen bonded network encompassing a free-NH2 moiety, Zn(II)-based metal–organic framework (MOF) (1), is used for the selective detection of antibiotics and toxic oxo-anions at the ppb level. The framework is able to detect the electronically dissimilar antibiotic sulfadiazine and nitrofurazone via fluorescence “turn-on” and “turn-off” processes, respectively. The antibiotic-triggered reversible fluoro-switching phenomena (fluorescence “on–off–on”) are also observed by using the fluorimetric method. An extensive theoretical investigation was performed to establish the fluoro-switching response of 1, triggered by a class of antibiotics and also the sensing of oxo-anions. This investigation reveals that the interchange of the HOMO–LUMO energy levels of fluorophore and analytes is responsible for such a fluoro-switchable sensing activity. Sensor 1 showed the versatile detection ability which is reflected by the detection of a carcinogenic nitro-group-containing drug “roxarsone”. In view of the sustainable environment along with quick-responsive merit of 1, an in situ MOF gel composite (1@CS; CS = corn starch) is prepared using 1 and CS due to its useful potential features such as biocompatibility, toxicologically innocuous, good flexibility, and low commercial price. The MOF composite exhibited visual detection of the above analytes as well as antibiotic-triggered reversible fluoro-switchable colorimetric “on–off–on” response. Therefore, 1@CS represents a promising smart sensing material for monitoring of the antibiotics and oxo-anions, particularly appropriate for the real-field analysis of carcinogenic drug molecule “roxarsone” in food specimens.

Metal–organic framework (MOF)-based fluorescence “turn-on” sensors

“…MOFs have also been used for the detection of antibiotic molecules. [121][122][123] With the increase in the population globally, the intake of antibiotics has significantly increased, which has a negative effect on the environment. 124 Also, the side effects associated with antibiotics negatively impact human health and cause several diseases.…”

Engineering of metal–organic frameworks (MOFs) for thermometry

“…MOFs possess several crucial structural features, such as a regular organic-inorganic network, 16,17 high crystallinity, 18 porosity, 19,20 flexibility, 21,22 stability, 23 hostguest interaction capability 24 and easy functionalization 25 with tuneable pore size. 26 These features make them amenable to numerous potential applications, including sensing, [27][28][29][30] catalysis, 31,32 gas adsorption and sequestration, [33][34][35] separation, 36 and bio-application. 37 Such structural features and potential applications can be finely modulated by judicial selection of the organic linker and metal ion.…”

Tactile Sensors: Hydroxyl Decorated Silver Metal–Organic Frameworks for Detecting Cr2O72–, MnO4–, Humic Acid, and Fe3+ Ions

“…It cannot be denied that carbon composites, nanomaterials, molecular probes, etc., have recently been used for contaminates determination in water using spectroscopic, electrochemical, spectrophotometric, and magnetic resonance-based techniques. − Despite these, metal–organic frameworks (MOFs) are well-established, and advanced bottom-up tools are used for detecting contaminants from water directly. In addition, cutting-edge methodologies have been explored to design new forms of periodic solids with diverse building blocks and edge-transitive nets. , Over the past few decades, the study of MOFs has attracted interest due to widespread applications in catalysis, magnetism, sensing, drug delivery, light emitting materials, water harvesting, and disease diagnostics and therapeutics. − MOFs are coordination compounds designed by metal ions and organic ligands.…”