Luminescence最新文献

A novel fluorescent “turn-on” probe, N′-((2-hydroxynaphthalen-1-yl) methylene)-5-methyl-2-phenyl-2H-1,2,3-triazole-4-carbohydrazide (G₃), was designed and synthesized. The structure was fully characterized by ¹H NMR, ¹³C NMR, and MS. G₃ exhibits highly selective and sensitive fluorescence enhancement toward aluminum ions in aqueous solution. Job's plot analysis, ¹H NMR titration, and mass spectrometric studies confirm a 1:1 binding stoichiometry between G₃ and Al³⁺, which is further supported by density functional theory (DFT) and quantum chemical calculations elucidating the sensing mechanism. Notably, the probe achieves an exceptionally low detection limit of 1.162 nM, outperforming most previously reported Al³⁺ sensors. Practical applicability was demonstrated through Al³⁺ detection in environmental water samples and the development of a portable swab test kit. Cytotoxicity assays reveal low cellular toxicity, while fluorescence imaging in HeLa cells and zebrafish confirms its biocompatibility and bioimaging capability. These results highlight G₃ as a promising probe with high sensitivity, excellent selectivity, and significant potential for applications in environmental monitoring and biological sensing.

Tirzepatide, a first-class dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist, has emerged as a breakthrough in the management of type 2 diabetes and obesity. Given its recent approval and expanding clinical applications, the development of accurate, sensitive, and efficient analytical methods for its determination in pharmaceutical formulations and biological matrices is critically important. In this study, a novel and efficient analytical probe was developed for the selective and sensitive determination of tirzepatide in pharmaceutical dosage form and spiked plasma. Acriflavine was employed as a fluorescent probe due to its strong native fluorescence, excellent stability, and high sensitivity to molecular interactions. The method was based on the formation of a stable 1:1 acriflavine–tirzepatide complex at pH 8.0, resulting in static fluorescence quenching measured at 505 nm following excitation at 451 nm. Validation in accordance with ICH guidelines confirmed the method's excellent linearity over 0.1–20 μg/mL (r = 0.9999), with a detection limit of 0.012 μg/mL and a quantitation limit of 0.036 μg/mL, alongside outstanding precision (RSD < 1%) and accuracy. Furthermore, greenness assessment using multiple evaluation tools confirmed the environmentally friendly nature of the method, highlighting its suitability for routine quality control, pharmacokinetic studies, and potential application to future GIP/GLP-1-based therapies.

A quick, eco-friendly, and economical approach for the synthesis of self-nitrogen doped carbon quantum dots (N-CQDs) utilizing onion extract was created in the current study. This method used a microwave to heat an onion for 4 min, providing a sustainable source of carbon and nitrogen. The provided N-CQDs exhibited great stability and a fluorescence quantum yield of 12.1% at λex/λem of 340/430 nm, respectively. The produced N-CQDs served as a successful nanoprobe for fluoride measurement, within a concentration range of 20–300 ng/mL with a detection limit of 4.557 ng/mL. In the presence of several potentially conflicting medications, the N-CQDs showed remarkable fluoride selectivity. For the assessment of water's fluoride content, a mean percentage recovery of 100.955 ± 0.416 was obtained. The N-CQDs were employed to measure fluoride in human saliva within the 50–1000 ng/mL concentration range, with a limit of detection of 15.693 ng/mL. Making use of AGREE and complexGABI and complexMoGABI approach, the suggested probe's greenness was assessed. Its good greenness was ascribed to the use of a low-cost plant, low-energy consumption through microwave-assisted synthesis, and avoiding dangerous chemicals and organic solvents. The blueness of the developed approach was assessed using the Blue Applicability Grade Index (BAGI).

Blue fluorescent carbon dots (CDs) were synthesized in this study from poly (butylene adipateco-terephthalate) (PBAT) and poly (ethylene terephthalate) (PET) waste through a sequential carbonization and hydrothermal treatment. The nanoparticles exhibited a spherical morphology with a narrow size distribution of 1.3–2.5 nm, abundant hydrophilic surface groups, and excellent dispersibility in aqueous solution. The CDs exhibited strong blue fluorescence with a quantum yield (QY) of 7.4% and remarkable stability. The fluorescence was selectively quenched by gefitinib primarily via a Förster resonance energy transfer (FRET) mechanism. The developed sensor showed a linear detection range of 0–30 μM, a low detection limit of 0.8433 μM, and outstanding anti-interference capability against common biomolecules and structurally similar drugs. The spiked recovery rates in real samples ranged from 96.7% to 103.0%, with the relative standard deviations (RSDs) less than 3.0%, demonstrating the probe's capability for detecting gefitinib in complex practical matrices. The proposed sensor shows great potential for applications in therapeutic drug monitoring and clinical diagnostics, offering a promising solution for both environmental sustainability and analytical science.

Stimuli-responsive luminescent materials that transduce environmental signals into optical outputs are of great interest for smart sensing and information materials. Metal halide perovskite nanocrystals (PNCs) have recently emerged as an appealing platform for smart luminescent materials, owing to their exceptional sensitivity to a wide range of external stimuli. These stimuli can be broadly classified into physical stimuli (e.g., temperature, mechanical stress, and light), chemical stimuli (including humidity, chemical vapors, and halide ions), and structural or chiral stimuli associated with phase transitions, lattice distortion, or coupling with chiral environments. This mini review summarizes recent advances in stimuli-responsive luminescence systems based on PNCs, with an emphasis on the underlying relationships between structure and property. We first outline the structural features and photophysical fundamentals of PNCs. Representative examples of hydrochromic, thermochromic, mechanochromic, chemical- and halide-responsive luminescence behaviors, as well as stimuli-switchable circularly polarized luminescence (CPL) and smart surface-ligand engineering of PNCs, are discussed. Finally, current challenges and future opportunities for designing robust, programmable, and multifunctional perovskite-based stimuli-responsive luminescent materials are briefly addressed.

A green, sustainable, and highly sensitive fluorimetric method was developed for the quantitative determination of the antidiabetic agents alogliptin, saxagliptin, and vildagliptin in bulk powders and commercial formulations. The assay relies on charge–transfer complexation with fluorescein in acetate buffer at drug-specific pH values, producing enhanced fluorescence at 513 nm (λ_ex = 470 nm). Under optimized conditions, linear responses were obtained within 2.00–50.00 μg/mL for saxagliptin, 1.00–30.00 μg/mL for vildagliptin, and 1.00–31.25 μg/mL for alogliptin, with detection limits of 0.54, 0.27, and 0.23 μg/mL, respectively. The corresponding quantification limits were 1.63, 0.81, and 0.70 μg/mL. The method exhibited excellent correlation coefficients across all ranges and was validated in accordance with ICH guidelines. Application to pharmaceutical tablets yielded results consistent with reported reference methods, confirming accuracy and precision without significant statistical differences. Greenness and sustainability were evaluated using multiple assessment tools (AGSA, GAPI, AGREE, MoGAPI, Eco-scale, CACI, BAGI, CaFRI, and MA tool), confirming the eco-friendly profile of the assay. The proposed method provides a reliable, green alternative for routine quality control of gliptins in pharmaceutical preparations.

This study introduces the first eco-friendly micellar method for the determination of roflumilast (ROL) in its pure form, pharmaceutical dosage form, and milk. A micellar solution of beta-cyclodextrin (ꞵCD) containing ROL showed high native fluorescence emission at 388 nm following excitation at 253 nm. Molecular docking confirmed the stable host–guest inclusion of ROL into the ꞵCD cavity, providing a molecular explanation for the observed fluorescence enhancement. The method was validated according to the requirements outlined in ICH Q2 R2 guidelines for method validation. The technique exhibited satisfactory linearity in the range of 400–1200 ng/mL with a high correlation coefficient value of 0.9996, showing high sensitivity with low detection and quantification limits of 161.0 and 185.0 ng/mL, respectively, with excellent accuracy and precision. The method's sustainability was evaluated using the green analytical procedure index, Eco-Scale, and whiteness assessment, indicating that the proposed method is eco-friendly.

Hydrogen sulfide (H₂S), classified as a Class III gaseous signaling molecule, plays a critical role in regulating a range of physiological and pathological processes, including vasodilation, oxidative stress balance, synaptic plasticity, and tumor metastasis. In recent years, the development of high-efficiency, high-sensitivity fluorescent probes has garnered significant attention due to their advantages in spatial and temporal resolution, minimal background interference, and capacity for deep tissue imaging. These characteristics have positioned fluorescent probes as essential tools for elucidating the dynamic distribution and underlying mechanisms of H₂S activity. This review systematically examines recent progress in near-infrared fluorescent probes, particularly those based on nucleophilic substitution, reduction reactions, and copper sulfide precipitation. The discussion emphasizes innovations in detection mechanisms, performance enhancements, and applications in biological systems. These advancements provide a theoretical foundation for a deeper understanding of H₂S biology and support the development of integrated diagnosis and treatment tools, thereby advancing the application of H₂S probes in life sciences, environmental monitoring, and clinical translation.

This study reports a facile hydrothermal synthesis of fluorescent sulfur- and nitrogen-doped carbon quantum dots (S-N-CQDs) using cost-effective solid precursors such as L-methionine, malonic acid, and ethylenediamine. The S-N-CQDs exhibited a high quantum yield of 43%, measured with quinine sulfate as the reference standard. Various characterizations using HRTEM, XRD, XPS, zeta potential analysis, UV–Vis spectroscopy, and fluorescence lifetime measurements. The S-N-CQD particles have a size range of 2–3.5 nm and a zeta potential of −24.4 mV. The fluorescence of S-N-CQDs remained stable across a broad range of pH and under continuous UV irradiation (365 nm). Further S-N-CQDs were successfully employed as a fluorescent probe for hydroquinone (HQ) detection, showing concentration-dependent fluorescence quenching. The probe demonstrated a detection limit of 75 nM, with a linear response in the range 10–40 μM (R² = 0.998), and exhibited excellent selectivity toward HQ. The application and reliability associated with fluorescent probes were demonstrated for the examination of HQ in real water samples. The results found that the one-pot hydrothermal synthesis method shows high sensitivity, selectivity, and accuracy for the detection of HQ, highlighting its potential for environmental monitoring and practical applications.

An off-type fluorescent Schiff base sensor S1, 6,6′-(1Z,1′Z)-hydrazine-1,2-diylidenebis(methaneylylidene)bis(3-(diethylamino)phenol), was synthesized and characterized for the selective sensing of Al(III) metal ion in aqueous medium. Sensor S1 exhibits distinct naked-eye colorimetric changes from yellow to bright orange with a bathochromic shift from 415 to 486 nm upon the addition of Al(III), corresponding to a 71 nm red shift in UV-Vis spectra. Moreover, fluorescence titration experiments in CH₃CN:H₂O (9:1, v/v) demonstrated that S1 functions as a selective and sensitive “off”-type probe for Al(III) ions under near-neutral aqueous conditions (pH 7–8) with a quenching efficiency of 82.5%. The sensor can detect Al(III) in water with the limit of detection (LOD) of 3.26 × 10⁻⁷ M with binding stoichiometry 1:1, supported by Job's plot, Benesi–Hildebrand, Stern–Volmer plot, and HRMS data, and binding constant (K_a) of 6.10 × 10⁴ M⁻¹ and a Stern–Volmer constant (K_SV) of 4.82 × 10⁶ M⁻¹, further indicating its strong affinity. This approach also exhibit significant implementation of Al(III) sensing in real samples including the ground water and tap water.