ACS Nano最新文献

Aqueous zinc-iodine (Zn-I₂) batteries, owing to their compelling combination of environmental friendliness, cost-effectiveness, and enhanced safety features, are regarded as promising candidates for large-scale energy storage systems. Nevertheless, the limited I₂/2I^- two-electron redox chemistry and nonuniform Zn deposition critically impair the energy density and cycling stability of aqueous Zn-I₂ batteries, hindering their practical deployment. Herein, multifunctional cyclohexylamine hydrochloride (CHAH) additive is introduced into the ZnSO₄ electrolyte, which synergistically enables a dendrite-free Zn anode for extended cyclability and simultaneously activates a stable four-electron 2I⁺/I₂/2I^- redox chemistry at the I₂ cathode. Combined experimental characterization and theoretical calculations reveal that the cyclohexylamine (CHA) reconstructs the Zn²⁺ solvation structure by displacing active H₂O, while fostering a nitrogen-rich solid electrolyte interphase on the Zn anode at the same time. It suppresses parasitic reactions and enables excellent Zn plating/stripping cycling for 2150 h at 1 mA cm^-2/1 mAh cm^-2. Furthermore, nucleophilic amine groups in CHA act synergistically with Cl^- to coordinate I⁺ by forming (2CHA)ICl, which improves four-electron 2I⁺/I₂/2I^- redox kinetics and achieves exceptional Zn-I₂ battery performances (256.3 mAh g^-1 at 10 A g^-1). This bilateral nitrogen interface chemistry mechanism offers key insights into the development of high-performance Zn-I₂ batteries.

Exosome (EXO) membrane proteins are attractive biomarkers for liquid biopsy, yet their heterogeneity makes it difficult to develop reliable antibody-based recognition reagents. Aptamers provide high-affinity and highly specific alternatives through the systematic evolution of ligands by exponential enrichment (SELEX), but the nanosized EXOs introduce substantial separation challenges that complicate SELEX workflows. Here, we present DeteRministic Evolution of Aptamers via a Microfluidic-integrated robotic platform (DREAMbot), an automated system engineered to execute multiround EXO-targeted aptamer selection with minimal human intervention. DREAMbot integrates a programmable pipetting robot with deterministic lateral displacement sorting and lipid-assisted magnetic isolation, enabling the automated purification and recovery of EXO-binding aptamers from cell-derived vesicles and molecular contaminants. This robotic-microfluidic workflow faithfully reproduces aptamer enrichment while substantially reducing hands-on burden compared to manual SELEX. Using cell-derived EXOs as targets, DREAMbot identified aptamers with nanomolar dissociation constants and high specificity toward GPC3-positive EXOs from both cultured cells and human serum. With its modular robotic-microfluidic architecture, DREAMbot provides a practical and accessible framework for automated aptamer discovery relevant to liquid biopsy applications.

Sodium-ion batteries (SIBs) are promising next-generation batteries as a sustainable alternative to lithium-ion systems, yet an understanding of the solid electrolyte interphase (SEI) is far from sufficient. Here, we develop a probing approach using redox mediator molecules to characterize subnanometric SEI pores, revealing that Na⁺ transport occurs through diffusion channels. By electrochemical analysis, differential electrochemical mass spectrometry, and theoretical calculations, the influences of solvent salts on SEI architecture have been studied. These findings offer fundamental knowledge beyond classical SEI models and provide both a powerful characterization tool and principles for electrolyte choice for SIBs.

The transition from right-handed B-DNA to left-handed Z-DNA represents one of the most dramatic structural changes in biology and plays a crucial role in gene expression and transcription. Monitoring this transition is essential for understanding fundamental biological processes, elucidating disease mechanisms, and developing more effective therapeutic strategies. Here, we present a label-free approach to distinguish between Z-DNA and B-DNA by detecting changes in the electrical current modulations as they translocate through a nanopore. This method enables real-time monitoring of B-to-Z and Z-to-B transitions and studying reaction kinetics at the single-molecule level. By directly capturing dynamic structural changes in DNA, our nanopore platform offers a powerful way to investigate DNA structural mechanics and study its interactions with small molecules or therapeutics, thereby advancing the development of versatile tools for studying biologically relevant DNA conformational switches with potential biotechnological applications.