Zinc ions (Zn²⁺) and reactive oxygen species (ROS) are critical regulators of cellular signaling, redox homeostasis, and physiological function. Dysregulation of either species is implicated in numerous diseases, including neurodegeneration, diabetes, and cancer. However, their dynamic interplay in living systems remains poorly understood due to the lack of probes capable of monitoring both analytes simultaneously with high specificity and spatial resolution.

Herein, we present the design and application of a dual-modal fluorescent probe, ZnROS-1, engineered for real-time, co-imaging of intracellular Zn²⁺ and ROS in live cells. The probe features a BODIPY-based fluorophore linked to a zinc-chelating moiety—2,6-pyridinedicarboxylic acid (DPA)—and a ROS-responsive boronate ester group positioned at the 4-position of the BODIPY core. This architecture enables distinct and sequential responses: upon binding Zn²⁺, the DPA ligand induces fluorescence enhancement via suppression of non-radiative decay pathways; concurrent exposure to ROS triggers hydrolysis of the boronate ester, leading to further emission increase and spectral shift toward longer wavelengths.

The probe exhibits excellent selectivity for Zn²⁺ over other metal ions, including Na⁺, K⁺, Ca²⁺, Mg²⁺, Fe²⁺, Cu²⁺, and Mn²⁺, with minimal interference from biological anions or amino acids.3483-12-3 custom synthesis Similarly, its response to ROS is highly specific, showing no significant signal change in the presence of thiols, nitric oxide, or common metabolites.107-35-7 site The two signals can be independently quantified: Zn²⁺ detection is achieved by measuring fluorescence intensity at 515 nm, while ROS levels are monitored via the ratio of intensities at 515 nm and 580 nm.

In live HeLa and SH-SY5Y cells, ZnROS-1 rapidly diffused across membranes and accumulated in the cytoplasm within 10 minutes. Confocal imaging revealed bright, uniform fluorescence that colocalized with mitochondrial markers, suggesting potential involvement in organelle-specific redox regulation. Upon addition of exogenous Zn²⁺ (10 μM), a sharp increase in green fluorescence was observed, confirming its responsiveness. Subsequent treatment with H₂O₂ (50 μM) induced a second wave of fluorescence increase and a visible color shift from green to yellow-red, enabling simultaneous visualization of both analytes.PMID:29262085

Time-lapse experiments demonstrated that ZnROS-1 could track dynamic changes during oxidative stress induction. In cells treated with hydrogen peroxide, the probe first detected elevated ROS levels, followed by Zn²⁺ release from intracellular stores—a phenomenon linked to metal ion dysregulation under oxidative conditions. This temporal sequence provides valuable insight into the crosstalk between redox imbalance and metal ion homeostasis.

Cytotoxicity assessments using MTT assays showed no significant cell death after 24 hours of incubation with up to 10 μM probe. The probe also exhibited good photostability and negligible degradation in serum-containing media over 6 hours, ensuring reliable performance in long-term imaging experiments.

Furthermore, the probe was applied in a model of neuronal degeneration, where Zn²⁺ dyshomeostasis and ROS overproduction are key pathogenic factors. In SH-SY5Y cells exposed to amyloid-beta peptides, ZnROS-1 clearly revealed a coordinated rise in both Zn²⁺ and ROS, supporting its utility in studying neurodegenerative mechanisms.

In conclusion, ZnROS-1 is a powerful dual-modal probe that enables precise, real-time, and simultaneous detection of Zn²⁺ and ROS in living cells. Its high selectivity, ratiometric output, and compatibility with standard microscopy platforms make it an ideal tool for investigating metal–redox interactions in health and disease. This work paves the way for advanced studies on cellular signaling networks and offers new opportunities for early diagnosis and targeted intervention in neurodegenerative and metabolic disorders.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