Giulia Moro

The escalating demand for sustainable environmental monitoring necessitates the development of field-deployable electrochemical sensors that harmonize marked analytical performances, mainly related to efficient charge transport, and good mechanical stability with eco-friendliness. Achieving this balance requires functional interfaces in which renewable materials, hierarchical organization, and interfacial electron-transfer properties are rationally coupled. Here, surface-deacetylated chitin nanocrystals (CsNCs) derived from seafood waste are approved to be versatile interfacial material for the realization of electrochemical sensing elements. We demonstrate that the surface degree of deacetylation, optimized through a systematic kinetic study, dictates the CsNCs' self-assembly ability, ultimately resulting in a suppression of chiral nematic ordering.The close interplay between surface chemistry and morphology serves as a precise chemical lever to modulate electrochemical performance, as revealed by electron-transfer kinetics and resistivity analysis. Increasing surface deacetylation generates chitosan-rich nanocrystal interfaces that preserve the crystalline rod-like core while lowering charge-transfer resistance and improving redox accessibility compared with conventional chitosan films. Exploiting these design rules, a CsNCs-based platform is developed for the indirect detection of glyphosate in water via Cu2+-mediated complexation. Notably, the biobased sensing film enables a "peel-and-reuse" cycle, facilitating rapid electrode regeneration and fulfilling the requirements of circular economy. Overall, this work establishes deacetylation-controlled CsNCs films as waste-biomass-derived electrochemical interfaces and provides transferable design rules linking surface chemistry, supramolecular organization, and charge transport in sustainable applied materials.

The escalating demand for sustainable environmental monitoring necessitates the development of field-deployable electrochemical sensors that harmonize marked analytical performances, mainly related to efficient charge transport, and good mechanical stability with eco-friendliness. Achieving this balance requires functional interfaces in which renewable materials, hierarchical organization, and interfacial electron-transfer properties are rationally coupled. Here, surface-deacetylated chitin nanocrystals (CsNCs) derived from seafood waste are approved to be versatile interfacial material for the realization of electrochemical sensing elements. We demonstrate that the surface degree of deacetylation, optimized through a systematic kinetic study, dictates the CsNCs' self-assembly ability, ultimately resulting in a suppression of chiral nematic ordering.The close interplay between surface chemistry and morphology serves as a precise chemical lever to modulate electrochemical performance, as revealed by electron-transfer kinetics and resistivity analysis. Increasing surface deacetylation generates chitosan-rich nanocrystal interfaces that preserve the crystalline rod-like core while lowering charge-transfer resistance and improving redox accessibility compared with conventional chitosan films. Exploiting these design rules, a CsNCs-based platform is developed for the indirect detection of glyphosate in water via Cu2+-mediated complexation. Notably, the biobased sensing film enables a "peel-and-reuse" cycle, facilitating rapid electrode regeneration and fulfilling the requirements of circular economy. Overall, this work establishes deacetylation-controlled CsNCs films as waste-biomass-derived electrochemical interfaces and provides transferable design rules linking surface chemistry, supramolecular organization, and charge transport in sustainable applied materials.

Bimetallic complexes are rapidly emerging as a valid and attractive class of emitters. In this presentation, we will describe a recent work concerning the yet unexplored electrochemiluminescence (ECL) properties of a series of heterobimetallic complexes of general structure Ir^III-M^I belonging to the class of ionic transition metal complexes (iTMCs). In the Ir^III-M^I series, the formally neutral cyclometalated iridium complex provides efficient photo- and electro-active properties to the molecular emitters. Whereas bulky M^I(gold or copper) metalloligand increases structural rigidity and chemical stability of the architecture, while enabling larger values for the radiative rate constant. A highly efficient ECL in the red region of the visible spectrum ( = 600 nm) can be achieved, which is stable in a wider range of applied potential. Moreover, the potential required to trigger ECL is much lower (~0.3-0.5 V) than that of the benchmark tris(2,2’-bipyridine)rutheniu(II), [Ru(bpy)₃]²⁺. Remarkably, the ECL quantum yield relative to [Ru(bpy)₃]²⁺ is up to six-fold higher, thus positioning this new heterobimetallic complexes amongst the brightest ECL-active emitters to date and possibly offering a platform onto which developing novel and even more efficient ECL probes for biosensing and bioimaging applications.

Ionic transition metal complexes (iTMCs) often suffer from low photoluminescence quantum yield, especially in the red to near‐infrared spectral region. Rational molecular design strategies unlock recovering the emission features efficiently. A potential solution is offered by bimetallic complexes, which are rapidly emerging as a valid and attractive class of emitters. In this work, the yet unexplored electrochemiluminescence (ECL) properties of a series of heterobimetallic complexes of general structure Ir ^III ‐M ^I are investigated, where the formally neutral cyclometalated iridium complex provides efficient photo‐ and electro‐active properties to the molecular emitters. Whereas bulky M ^I (gold or copper) metalloligand increases structural rigidity and chemical stability of the architecture while enabling larger values for the radiative rate constant. The Ir ^III ‐M ^I shows highly efficient red ECL at λ _{em , max} = 600 nm, which is stable in a wider range of applied potential. The activation is triggered at 0.45–0.65 V, ca. 0.3–0.5 V lower than that of tris ‐(2,2′‐bipyridyl) ruthenium(II) complex, [Ru(bpy) ₃ ] ²⁺ . Remarkably, the ECL quantum yield relative to [Ru(bpy) ₃ ] ²⁺ is up to six‐fold higher, thus positioning this new series of iTMCs amongst the brightest ECL‐active emitters to date and possibly offering a platform to develop novel and even more efficient ECL probes for biosensing and bioimaging applications.

The dissemination of sensors is key to realizing a sustainable, ‘intelligent’ world, where everyday objects and environments are equipped with sensing capabilities to advance the sustainability and quality of our lives—e.g. via smart homes, smart cities, smart healthcare, smart logistics, Industry 4.0, and precision agriculture. The realization of the full potential of these applications critically depends on the availability of easy-to-make, low-cost sensor technologies. Sensors based on printable electronic materials offer the ideal platform: they can be fabricated through simple methods (e.g. printing and coating) and are compatible with high-throughput roll-to-roll processing. Moreover, printable electronic materials often allow the fabrication of sensors on flexible/stretchable/biodegradable substrates, thereby enabling the deployment of sensors in unconventional settings. Fulfilling the promise of printable electronic materials for sensing will require materials and device innovations to enhance their ability to transduce external stimuli—light, ionizing radiation, pressure, strain, force, temperature, gas, vapours, humidity, and other chemical and biological analytes. This Roadmap brings together the viewpoints of experts in various printable sensing materials—and devices thereof—to provide insights into the status and outlook of the field. Alongside recent materials and device innovations, the roadmap discusses the key outstanding challenges pertaining to each printable sensing technology. Finally, the Roadmap points to promising directions to overcome these challenges and thus enable ubiquitous sensing for a sustainable, ‘intelligent’ world.

In the era of liquid biopsies, the reliable and cost-effective detection and screening of cancer biomarkers has become of fundamental importance, thus paving the way for the advancement of research in the field of point-of-care testing and the development of new methodologies and technologies. Indeed, the latter ones can help designing advanced diagnostic tools that can offer portability, ease of use with affordable production and operating costs. In this respect, impedance-based biosensing platforms might represent an attractive alternative. In this work, we describe a proof-of-concept study aimed at designing portable impedimetric biosensors for the monitoring of human urokinase-type plasminogen activator (h-uPA) cancer biomarker by employing small synthetic receptors. Aberrant levels of h-uPA were correlated with different types of cancers. Herein, we report the use of two bicyclic peptides (P₂ and P₃) which have been engineered to bind h-uPA with high affinity and exquisite specificity. The synthetic receptors were immobilized via biotin-streptavidin chemistry on the surface of commercial screen-printed electrodes. The impedimetric changes in the electrode/solution interface upon incubation of spiked h-uPA samples in the presence of a redox probe were followed via electrochemical impedance spectroscopy. The P₃-based impedimetric assay showed the best outcomes in terms of dynamic range and linearity (0.01–1 μg mL⁻¹) and sensitivity (LOD = 9 ng mL⁻¹). To fully assess the performances of P₃ over P₂, and to compare the label-free architecture vs. labelled architecture, a voltammetric assay was also developed.