A facile and efficient synthesis method is essential for developing practical fluorescent probes capable of real-time detection of toxic metal ions in complex biological environments. In this work, we report a one-pot strategy for the rapid fabrication of red-emissive bimetallic gold/silver nanoclusters (DG-Au/AgNCs) with exceptional performance in detecting mercury(II) ions (Hg²⁺) within living systems. The synthesis involves mixing chloroauric acid and silver nitrate at optimized molar ratios (1:2), followed by addition of glutathione (GSH) and dithiothreitol (DTT) as reductants and surface ligands. The reaction proceeds under mild conditions—55 °C for 36 hours—with stirring, resulting in the formation of stable, monodisperse nanoclusters with an average diameter of approximately 3 nm, as confirmed by transmission electron microscopy (TEM). The resulting DG-Au/AgNCs exhibit intense red fluorescence centered at 665 nm when excited at 340 nm, attributed to the synergistic electronic interaction between Au and Ag atoms in the alloy core. This emission wavelength is particularly advantageous for in vivo applications, as it avoids overlap with the autofluorescence spectra of most biological tissues. Fourier-transform infrared spectroscopy (FTIR) analysis confirms the successful attachment of GSH and DTT ligands via Au–S bonds, with free -NH₂, -COOH, and -SH groups remaining available on the surface. The presence of these functional groups enhances water solubility and enables selective recognition of Hg²⁺ through strong coordination with thiol groups. Upon exposure to Hg²⁺, the fluorescence intensity decreases rapidly and proportionally, with a limit of detection as low as 1.01 nM. The response time is less than 1 minute, allowing for immediate assessment of ion levels. Notably, the probe shows negligible interference from common cations such as Na⁺, K⁺, Ca²⁺, Mg²⁺, Zn²⁺, and Cu²⁺, even at concentrations up to 100 µM. The entire synthesis process is simple, scalable, and does not require post-functionalization steps, making it highly suitable for practical deployment. These features collectively position DG-Au/AgNCs as a robust, user-friendly platform for sensitive and selective Hg²⁺ sensing in both environmental and biomedical contexts.
The development of reliable, on-demand sensing tools for heavy metals demands a balance between simplicity, sensitivity, and biological compatibility. Conventional analytical methods often rely on expensive instrumentation and skilled personnel, limiting their accessibility in field settings. Fluorescent nanosensors offer a promising alternative due to their ease of use, fast response, and potential for integration into portable devices. However, many existing probes suffer from poor stability, low quantum yield, or non-specific binding. To overcome these limitations, we engineered a bimetallic nanocluster system that combines the optical advantages of Au/Ag alloys with the functional versatility of dual organic ligands. By using GSH and DTT simultaneously during synthesis, we achieve simultaneous reduction, stabilization, and functionalization—eliminating the need for additional modification steps. This one-pot approach ensures high reproducibility and simplifies manufacturing. The resulting DG-Au/AgNCs demonstrate excellent photostability, maintaining over 90% of their initial fluorescence intensity after 24 hours under continuous irradiation. They are also resistant to bleaching and remain stable across a broad pH range (4–10), which is critical for application in diverse physiological environments.Dotriacontane Autophagy X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDS) confirm the presence of Au, Ag, S, C, N, and O elements, with a calculated atomic ratio of Au:Ag:S = 1:0.4-Methylquinaldine Drug Intermediate 43:1.PMID:35196483 58, indicating effective ligand coverage and alloy formation. The strong chemical stability of the Au–S and Ag–S bonds further enhances the probe’s durability. These characteristics make DG-Au/AgNCs ideal candidates for long-term monitoring in live cells and whole organisms. The ability to synthesize high-performance sensors in a single step represents a significant advancement toward point-of-care diagnostics and real-time environmental surveillance. This approach paves the way for the next generation of smart nanomaterials designed for dynamic, in situ detection of hazardous pollutants.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com