Bioactive NAD⁺ Regeneration Promoted by Multimetallic Nanoparticles Based on Graphene–Polymer Nanolayers

The concentration of nicotinamide adenine dinucleotide oxidized form (NAD⁺) changes during aging, and the production of NAD⁺ can significantly affect both health span and life span. However, it is still of great challenge to regenerate NAD⁺ from its precursors. Herein, we introduce a method to prepare multimetallic nanoparticles (including Au, Pt, Cu, and MgO) that can efficiently promote the conversion of NADH to NAD⁺. The nanoparticles are made by mixing reduced graphene oxide–polyethyleneimine–polyacrylic acid nano-films with metallic salts, where four different metal ions are reduced and grow at the surface of the nanolayers. The morphology, size, and growth rate of nanoparticles can be controlled by adding surfactants, applying an electric field, and so forth. Our multimetallic nanoparticles exhibit excellent catalytic performance that a complete conversion of NADH to NAD⁺ can be finished in 3 min without introducing additional oxygen. This work presents a way for the preparation of multimetallic nanoparticles to promote NAD⁺ regeneration, which shows great promise for the future design of high-performance materials for antiaging.