A Novel Method for Generating H2 by Activation of the μAl-Water System Using Aluminum Nanoparticles

Biodegradable Monometallic Aluminum as a Biotuner for Tumor Pyroptosis

Pyroptosis is an effective anti-tumor strategy. However, monometallic pyroptosis biotuners have not been explored until now. Here, we discover for the first time that biodegradable monometallic Al can act as a pyroptosis biotuner for tumor therapy. pH-sensitive Al nanoparticles (Al@P) are obtained by equipping polyethylene glycol-b-(poly(methyl methacrylate)-co-poly(4-vinylpyridine), which can exert their effect at the tumor site without affecting normal cells. The H2 and Al3+ release by Al@P in the acidic environment of tumors disrupts the redox balance and ionic homeostasis in tumor cells, thus generating large amounts of reactive oxygen species (ROS), leading to caspase-1 activation, gasdermin D cleavage, and IL-1β/LDH release, which induces canonical pyroptotic death. Meanwhile, the prodrug Doxorubicin (Pro-DOX) is successfully loaded onto Al@P (Al@P-P) and can be activated by ROS to release DOX in the tumor cells, thus further improving the tumor-killing efficiency. Ultimately, Al@P-P is degradable and exhibits efficient tumor inhibition.

Silver-Assisted Hydrogen Evolution from Aluminum Oxidation in Saline Media

A swarf of aluminum alloy with high corrosion resistance and ductility was successfully converted into fine hydro reactive powders via ball milling with silver powder and either lithium chloride or gallium. The latter substances significantly intensified particle size reduction, while silver formed 'cathodic' sites (Ag, Ag2Al), promoting Al corrosion in aqueous saline solutions with hydrogen generation. The diffraction patterns, microphotographs, and elemental analysis results demonstrated partial aluminum oxidation in the samples and their contamination with tungsten carbide from milling balls. Those factors were responsible for obtaining lower hydrogen yields than expected. For AlCl3 solution at 60 °C, Al-LiCl-Ag, Al-LiCl, Al-Ga-Ag, and Al-Ga composites delivered (84.6 ± 0.2), (86.8 ± 1.4), (80.2 ± 0.5), and (76.7 ± 0.7)% of the expected hydrogen, respectively. Modification with Ag promoted Al oxidation, thus providing higher hydrogen evolution rates. The samples with Ag were tested in a CaCl2 solution as well, for which the reaction proceeded much more slowly. At a higher temperature (80 °C) after 3 h of experiment, the corresponding hydrogen yields for Al-LiCl-Ag and Al-Ga-Ag powders were (46.7 ± 2.1) and (31.8 ± 1.9)%. The tested Ag-modified composite powders were considered promising for hydrogen generation and had the potential for further improvement to deliver higher hydrogen yields.