The use of nanopolymers in anti-aging and regenerative skincare has emerged as a transformative advancement in dermatological science. Specific nanopolymeric systems such as chitosan nanoparticles, hyaluronic acid nanogels, poly(lactic-co-glycolic acid) (PLGA) nanospheres, dendrimers, and polymeric micelles have demonstrated significant potential in enhancing topical delivery and skin regeneration. These nanoscale polymers (1–100 nm) offer tunable physicochemical properties that enable efficient encapsulation, targeted delivery, and controlled release of active ingredients, including retinoids, peptides, antioxidants, and growth factors. Their small size and surface modifiability improve penetration across the stratum corneum and facilitate interaction with dermal fibroblasts, promoting collagen synthesis, enhanced hydration, and cellular renewal. In anti-aging applications, nanopolymers reduce wrinkles, fine lines, and hyperpigmentation by improving bioavailability and stability of sensitive compounds such as vitamins and retinoids. In regenerative dermatology, nanopolymeric scaffolds and nanocarriers support wound healing, angiogenesis, and extracellular matrix remodeling. Despite their promising benefits, concerns regarding long-term safety, regulatory frameworks, and production scalability remain. Continued research into biodegradable and biocompatible nanopolymers is expected to further advance personalized and precision skincare strategies. This review highlights the mechanistic roles and therapeutic potential of nanopolymers in reshaping modern anti-aging and regenerative skincare.

Hybrid aluminum matrix composites (HAMCs) reinforced with graphene nanoplatelets (GNPs) and secondary reinforcements have emerged as promising lightweight structural materials due to their superior strength, wear resistance, and multifunctional performance. This review critically evaluates recent developments in GNPs-reinforced HAMCs, categorizing them into carbide-assisted, oxide-assisted, carbonaceous, and emerging sustainable hybrid systems. The influence of processing routes including semi-solid stir casting (compocasting), ultrasonic-assisted stir casting (UASC), powder metallurgy (PM), friction stir processing (FSP), accumulative roll bonding (ARB), and laser powder bed fusion (L-PBF) on reinforcement dispersion, interfacial bonding, and resultant properties (grain refinement, load-transfer mechanisms, etc.) is systematically discussed. Further, particular emphasis is placed on the role of the hybrid reinforcements in improving the mechanical and tribological performances of the HAMCs in reference to their processing techniques. Comparative analysis reveals that carbide-assisted systems provide the highest strengthening response, where Al/(GNPs+SiC) composites achieve tensile strengths up to 589 MPa through severe grain refinement, while GNPs+WC systems exhibit nearly 350% relative strength enhancement. Among oxide-assisted systems, L-PBF fabricated AA2024/(0.2GNPs+1ZrO₂) (wt.%) composites attain a peak tensile strength of 624 MPa after T6 treatment due to the formation of a crack-free bimodal microstructure. Carbonaceous hybrids such as reduced graphene oxide (rGO)+CNTs systems demonstrate an excellent balance between strength (460 MPa) and ductility (31.6%) through interconnected carbon networks that suppress crack propagation. Tribologically, graphene-based tribo-films significantly reduce friction and wear, with GO+CNTs hybrids achieving a minimum coefficient of friction of 0.295, whereas GNPs+B₄C and GNPs+waste-derived Al hybrid systems exhibit excellent wear resistance with wear rates as low as 1.9 × 10⁻³ mm³ m^-1. The review further highlights key challenges including reinforcement agglomeration, porosity, and interfacial instability at higher GNPs loadings (>1–2 wt.%). Overall, the study provides a comparative and data-driven framework for designing next-generation HAMCs for aerospace, automotive, defense, and thermal-management applications.