Nature-based Solutions (NbS) offer a promising, sustainable framework for addressing urban environmental challenges by harnessing the intrinsic functions of natural ecosystems. Defined as economically viable strategies inspired by nature, NbS aim to protect, manage, and restore ecosystems for mutual benefits to both people and nature. In urban and peri-urban contexts, NbS, such as green infrastructure and bioremediation, provide effective approaches to mitigating climate change, enhancing soil, air and water quality, reducing urban heat, and restoring ecological balance. Green infrastructure, comprising parks, urban forests, green roofs, and wetlands, has been shown to improve soil quality by enhancing organic carbon, nitrogen, and phosphorus accumulation, as well as fostering biodiversity. Complementarily, bioremediation strategies, including microbial remediation and phytoremediation, have proven effective in decontaminating soils laden with heavy metals, petroleum hydrocarbons, microplastics, and other pollutants, while promoting soil fertility and ecosystem services. Despite their demonstrated benefits, the efficacy of NbS is influenced by environmental factors such as soil pH, temperature, oxygen availability, and pollutant diversity. In addition, while NbS continue to evolve and their integration into urban planning represents a vital step toward creating resilient, healthy, and sustainable cities, their application in urban environments remains fragmented. Therefore, further research is required to optimize NbS interventions, scale up their implementation, and evaluate long-term impacts under urban conditions characterized by anthropogenic stressors. This review examines green infrastructure and bioremediation strategies, highlighting key case studies and evaluating their effects on soil quality and overall remediation outcomes.

A ratiometric electrochemical sensor featuring a benzoquinone-modified vertically aligned mesoporous silica film (BQ/VMSF) has been developed for the accurate detection of diclofenac (DCF), a widely utilized non-steroidal anti-inflammatory drug. The design process employed the Electrochemical assisted self-assembly (EASA) technique to grow a thiol-functionalized mesoporous silica film on a carbon screen-printed electrode, which was further modified with benzoquinone via click chemistry. Characterization using Transmission Electron Microscopy (TEM), Fourier-Transform Infrared Spectroscopy (FTIR), Cyclic Voltammetry (CV), and Electrochemical Impedance Spectroscopy (EIS) confirmed the successful synthesis and optimal functionality of the mesoporous structure. In this configuration, benzoquinone serves as an internal redox reference, generating one redox signal, while the electrochemical oxidation of diclofenac produces a second redox signal. The sensor's output is derived from the ratio of these two signals, I_DCF/I_BQ, enhancing its sensitivity and selectivity for diclofenac detection. The sensor, tested through Differential Pulse Voltammetry (DPV), exhibited a linear response range from 1 to 10 μM for diclofenac and a remarkably low limit of detection (LOD) of 0.73 μM. Application of the sensor for diclofenac analysis in pharmaceutical formulations demonstrated recovery rates ranging from 97.68 % to 101.79 % and relative errors below 2.32 %, affirming its practical utility.

Invited for this issue's Front Cover is the group of Electroanalytical Chemistry of Prof. Luigi Falciola. The Cover Feature shows the photoelectrochemical sensor prepared by covering AuNPs with a thin layer of TiO₂. The obtained hybrid material, which exploits synergistically the properties of its components, was used to monitor ciprofloxacin, exhibiting a response only once irradiated. Good performances were obtained using a low‐power LED. Such discovery may pave the way for future in situ applications in environmental monitoring. Read the full text of the Research Article at 10.1002/celc.202201136.

A photoelectrochemical sensor composed of a heterojunction between titanium dioxide and gold nanoparticles was fabricated and used for the determination of ciprofloxacin, a widely used, but environmentally toxic third‐generation antibiotic. This material has been extensively characterized from the morphological, electrochemical and photoelectrochemical points of view, comparing it with the respective counterparts. It has been demonstrated that only the presence of the heterojunction allows the detection of ciprofloxacin, thanks to the properties of gold nanoparticles combined with those of titanium dioxide. These increased performances have allowed the detection of the analyte even with low power sources and wavelengths in the visible region, obtaining good detection limits and excellent resistance to possible interferents. Thanks to this, the future implementation of these sensors in integrated circuits for online and onsite analysis is foreseen.

The toxicity of atmospheric particulate matter (PM) depends not only on its burden in air, but also on its chemical composition, which affects its ability to induce oxidative stress at the cellular level through reactive oxygen species (ROS) formation. The oxidative potential (OP) of PM has been proposed as an integrative metric for PM toxicity; however, standardized analytical protocols are still lacking. In this study, the performance of the ascorbic acid (AA) assay was evaluated for the determination of PM oxidative potential. A total of 32 filters were analysed, corresponding to 16 filters per site (urban traffic and rural background) and eight filters per year (2020 and 2021). For each selected month (January, May, August, and November), the daily filters corresponding to the minimum and maximum PM₁₀ mass concentrations within that month were chosen. Ascorbic acid depletion was monitored spectrophotometrically at 265 nm under physiological conditions (phosphate buffer, PB, 37 °C). The method was tested using aqueous solutions containing individual metals considered to play a major role in the oxidative behaviours of PM (Cu, Cr, Fe, Mn, Ni and Zn) and four standard reference materials (SRMs). This acellular test was then applied to atmospheric PM₁₀ collected in 2020–2021 at the two monitoring sites in the Turin metropolitan area (Italy). Among the individual metals, Cu showed the highest oxidative activity, consistent with the literature data; BCR 176 showed the highest oxidative activity. Urban PM₁₀ samples exhibited higher oxidative potential (0.12–0.60 nmol AA min⁻¹ m⁻³) than suburban samples (0.10–0.38 nmol AA min⁻¹ m⁻³). Metal concentrations in the PM₁₀ samples were determined by ICP-OES and ICP-MS in both acid-digested samples and PB extracts used for OP determination, allowing for comparison between the total and bioaccessible metal fractions. To the best of our knowledge, this is the first study to investigate the relationship between PM₁₀ oxidative potential and its total and bioaccessible elemental composition in the Turin metropolitan area. Site characterization was expanded by quantifying PM₁₀ carbon fractions (EC/OC and brown carbon) through multiwavelength thermal/optical carbon analysis following the EUSAAR_2 protocol. Because of the sampling strategy adopted and the limited number of processed samples, the seasonal and between-site comparisons reported in this study refer specifically to the analysed samples. The combined evaluation of OP and ICP-based elemental composition provides insights into the role of transition metals in PM-induced oxidative stress and supports the integration of OP measurements into air quality assessment frameworks.