Innovative advancements in the development of high-performance, eco-friendly adhesives are critical for meeting the demands of diverse applications in various industries. This study reports a significant leap in adhesive technology by enhancing the interfacial toughness and versatility of polyvinyl alcohol (PVA) through complexation with 1-nm Keggin-type polyoxotungstate clusters (POTs) carrying specific negative charges. The POT-PVA nanocomposites exhibit superior adhesion to hydrophilic surfaces, attributed to their high crosslinking densities and exceptional fracture energies surpassing 6.23 kJ·m⁻². These adhesives, endowed with high flexibility and a wealth of surface hydroxyl groups, are uniquely suited for application on a wide array of substrates including glass, steel, aluminum, and beyond, demonstrating their broad applicability. Specifically, the reduction in PVA crystallinity due to the chaotropic effect of POTs, which significantly enhances polymer chain dynamics. This enhancement confers robust adhesive properties at extreme temperatures, from the cryogenic −196 °C to the high-temperature threshold of 100 °C. By capitalizing on the chaotropic effects of charged POTs, the study achieves a notable enhancement in the adhesive capabilities of the POT-PVA nanocomposites, paving the way for the development of for eco-friendly and cost-effective adhesives engineered to withstand extreme conditions.

Obesity is closely related with insulin resistance and chronic inflammation. Here, we report that unsaturated lipid-modified polyoxovanadates (ULPOVs) can restrict weight gain of diet-induced obese mice and improve their glycemic control and obesity-associated inflammation. Oral administration of the sub-nanosized ULPOVs at a low dosage for 7 weeks reduces the body weight and almost normalizes the blood glucose levels of obese mice fed on a high-fat diet. ULPOV treatment increases the activity of the nuclear receptor peroxisome proliferator-activated receptor γ (PPARγ) and reduces intestinal caloric intake, which may be the main reason for blood sugar and body weight control. In addition to insulin-sensitizing, PPARγ activation induced by ULPOV treatment in obese mice with atopic dermatitis (AD) promotes the type 2 T helper (T_H2) cell selective responses and therapeutic effects on immune dysregulation caused by obesity. These data suggest sub-nanosized polyoxovanadate clusters as a class of potential candidates to relieve symptoms accompanied by diet-induced obesity.

Long-lasting protective immune responses are expected following vaccination. However, most vaccines alone are inability to evoke an efficient protection. The combinatory administration of adjuvants with vaccines is critical for generating the enhanced immune responses. Herein, with biocompatible poly(4-vinylpyridine) (P4VP) as template, 2.5 nm iron/molybdenum oxide cluster, {Mo₇₂Fe₃₀}, is applied as an adjuvant to co-assemble with antigens of Mycobacterium bovis via hydrogen bonding at molecular scale. Molecular scale integration of the antigens and {Mo₇₂Fe₃₀} and their full exposure to body fluid media contribute to the augmentation of both humoral and cellular immune responses of the vaccines after inoculation in mice. Anti-inflammatory factor IL-10 gradually increases after 2 weeks followed by a final back to normal level by the 5th week. The balance between proinflammatory cytokines and anti-inflammatory factors suggests that immune system can be activated in the early stage of infection by the antigens carried by the supra-particles and secrete acute inflammatory factors for host defense and anti-inflammatory factors for immune protection.