Angiotensin Ⅱ is a key regulator of blood pressure and an important biomarker in vascular disease, but meaningful comparison of laboratory results depends on reliable measurement standards. Researchers have now developed a candidate reference material for angiotensin Ⅱ using two independent analytical approaches. The methods produced highly consistent results, while further testing showed good homogeneity, long-term stability, and low measurement uncertainty. Verification against an internationally recognized reference material provided additional support for the assigned value. The new material could provide laboratories with a common benchmark for method validation, quality control, and more comparable angiotensin Ⅱ measurements.

Low-quality brines represent an abundant and valuable resource for sustainable lithium supply, but their high Mg²⁺ concentrations and high Mg²⁺/Li⁺ ratios make the separation of Mg²⁺ and Li⁺ particularly challenging. A research team at Tsinghua University has developed a polyelectrolyte-intercalated graphene oxide membrane with tunable interlayer spacing, in which the effective interlayer gallery width was controlled through counter-ion adsorption, enabling efficient Mg²⁺/Li⁺ separation under high Mg²⁺ concentrations and high Mg²⁺/Li⁺ ratios through practical pressure-driven filtration.

Stable quantum dot (QD) inks are critical yet challenging for advancing the efficiency and scalability of solution-processed optoelectronic devices. PbS-PbI₂ QDs are attractive for their superior passivation and inter-dot coupling, but require strongly-coordinating alkylamine solvents which continuously etch the QDs and lead to rapid ink degradation. Research teams from Northeast Normal University in China and Jeonbuk National University in Korea reported a vapor-assisted pre-solvation strategy, extending the storage-lifetime of PbS-PbI₂ QDs over 60 days, ensuring outstanding thermal robustness and demonstrating scalable manufacturing potential of QDs.

Cu-doped Er₂O₃ catalysts (Cu-Er₂O₃-x) are synthesized to overcome kinetic, selectivity and proton supply issues of CO₂RR to CH₄. Cu doping creates a strong built-in electric field (BIEF) via charge redistribution, shortening *H-catalyst distance, boosting water dissociation and optimizing *CHO adsorption. The best Cu-Er₂O₃-6 reaches 60.79% CH₄ Faradaic efficiency with stable performance over 24 h. Characterizations and DFT verify BIEF accelerates proton transfer and lowers the barrier of the rate-determining *CHO→*CH₂O step. This work proposes a BIEF regulation strategy to design high-selectivity CH₄ electrocatalysts for carbon neutrality.

As electronic devices become increasingly connected, hardware authentication must move beyond stored digital secrets that can be copied or emulated. Researchers developed a graphene-based optical physical unclonable function that uses different combinations of red, green, and blue light as programmable challenges. A transformer-based model converts the resulting diffraction patterns into compact binary response units, demonstrating a route toward spectrally programmable optical authentication for future hardware security in connected devices and edge systems.

Researchers have developed a chip-scale platform for ultrawide-angle, two-dimensional optical beam steering. The system integrates a silicon photonic integrated circuit, freeform micro-optical reflectors, and a metasurface to transform guided light into high-quality free-space beams and direct them across a measured 161° field-of-view while maintaining nearly diffraction-limited beam quality. This compact, scalable architecture offers a pathway toward inter-satellite optical links, airborne LiDAR, point-to-point optical wireless communications, and other applications requiring agile, wide-angle beam control.