Aatika Nizam

A multifunctional supramolecular host–guest system based on an ESIPT-active Schiff base ligand (E)-N′-(5-bromo-2-hydroxybenzylidene)-2-fluorobenzohydrazide monohydrate (FHMB) has been designed and confirmed through single-crystal X-ray diffraction analysis for multichannel heavy-metal ion sensing and explored as a potential angiotensin-converting enzyme (AnCE) inhibitor. FHMB exhibits excitation-dependent dual emission arising from keto–enol tautomerism, enabling sensitive modulation of fluorescence through excited-state intramolecular proton transfer regulation. Complexation with Zn2+, Cd2+, and Pb2+ ions induces distinct turn-on fluorescence responses, characterized by distinct color outputs, allowing for simultaneous and differential detection in aqueous media. In contrast, FHMB exhibits exceptional selectivity toward Zr4+, producing a pronounced ratiometric fluorescence response under different sensing conditions. Binding stoichiometry and thermodynamics were elucidated using Job’s plot, Benesi–Hildebrand, and BindFit analyses, while 1H NMR, SEM–EDX, and elemental mapping confirmed metal-induced coordination and supramolecular reorganization. Practical applicability is validated through solid-state test kits, real-water sample analysis, plant-based Zn2+ imaging, and pharmaceutical zinc tablet detection. Furthermore, molecular docking studies against Drosophila and human AnCE reveal favorable binding interactions, particularly for the FHMB_Cd complex, indicating promising inhibitory potential. Collectively, this work presents a dual-functional supramolecular platform integrating environmental heavy-metal sensing with prospective biochemical modulation, highlighting its relevance for analytical, environmental, and biomedical applications.

This study demonstrates the efficient synthesis of diarylthioethers via C–S cross-coupling between diverse aryl halides and arylthiols utilizing a magnetically retractable Fe ₃ O ₄ @SiO ₂ –PrNH ₂ –SA–Cu( ii ) nanocatalyst using K ₂ CO ₃ as a base in DMF.

A novel green synthesis approach was developed for the fabrication of a g-C ₃ N ₄ /ZrTiO ₄ /V ₂ O ₅ nanocomposite using a hormone-treated plant extract for photocatalytic remediation of organic pollutants.

The development of dual-state emissive (DSE) organic luminogens has elevated the ease of recognition of various biological analytes, which demonstrates the multifaceted potential of dual-state emitters. Therefore, in this study, we synthesised a dual-state emissive excited-state intramolecular proton transfer (ESIPT)-based organic luminogen, (E)-4-(5-bromo-2-hydroxybenzylideneamino)-2,3-dimethyl-1-phenyl-1,2-dihydropyrazol-5-one (ANMB), exhibiting excitation-dependent phototunability with large Stokes shifts of 109 nm and 155 nm in both the solution and solid states, respectively, underscoring its potential as a biosensor. The metal-chelating ability of ANMB was investigated, revealing significant fluorescence quenching upon coordination with Cu²⁺ ions, leading to 96% reduction in emission intensity. The introduction of biological analytes, such as amino alcohols, enabled fluorescence recovery, where ANMB demonstrated enantioselective recognition: a single emission peak for the S-enantiomer and dual emission peaks for the R-enantiomer. Furthermore, ANMB demonstrated high selectivity for hydrazine detection in both the solution and solid states, with new emission bands observed at 411 nm and 432 nm, respectively, indicating a fluorescence shift from green to blue. Complementarily, ANMB was successfully applied for real-time imaging of hydrazine in food and plant samples, showcasing its practical adaptability. Additionally, in silico molecular docking studies were performed, revealing the potential therapeutic activity of ANMB against diarrheal targets. Overall, this work highlights the multifunctionality and tunability of DSE–ESIPT-based organic luminogens, positioning ANMB as a promising candidate for the selective recognition of biologically significant analytes in analytical and real-world contexts.

α-MnMoO ₄ nanocubes serve as a bifunctional material, acting as a light-driven photocatalyst for the degradation of organic pollutants and as a heterogeneous catalyst for conversion of o -phenylenediamine into 2-substituted benzimidazole derivatives.

Optical biosensors are transformative tools in point-of-care diagnostics, revolutionising biosensing and offering sensitive, selective, rapid, and often relevant and label-free clinical diagnosis.

A thiophene-based fluorescent probe system integrating electron donor, fluorophore, and recognition units enables effective ICT and PET mechanisms, demonstrating high sensitivity, selectivity, and specificity for chemical and biological sensing.

This work demonstrates a novel, green synthesis route for ZnMn ₂ O ₄ nanoparticles that uniquely integrates environmental remediation and forensic applications.