The regeneration of enzymatic cofactors by cell-free synthetic modulesi sak ey step towards producing ap urely synthetic cell. Herein, we demonstrate the regeneration of the enzyme cofactor NAD + by photo-oxidation of NADH under visible-light irradiation by using metal-free conjugated polymer nanoparticles. Encapsulation of the light-activen anoparticles in the lumen of polymeric vesicles produced af ully organic module able to regenerate NAD + in an enzyme-free system.T he polymer compartment conferred physical and chemicala utonomy to the module, allowing the regenerationo fN AD + to occur efficiently,e ven in harshc hemical environments. Moreover,w e show that regeneration of NAD + by the photocatalyst nanoparticles can oxidize am odel substrate, in conjunction with the enzymeg lycerol dehydrogenase. To ensure the longevity of the enzyme, we immobilizedi tw ithin ap rotectives ilica matrix;t his yieldede nzymatic silican anoparticles with enhanced long-term performance and compatibility with the NAD + -regeneration system.The immobilizationo re ncapsulationo ff unctional parts in artificial compartmentsi sapowerful way to create responsive autonomous objects, or functional modules, that displaylocalized input-output properties. [1] Synthetic biology uses artificially designed modules as systems that can reproduce simple cell-like activity and even mimic rudimentary cellular behavior. [2] Some examples include the cell-free synthesis of ATP, [3] cytoskeleton and microtubule reconstitution, [4] self-replication of giant vesicles, [5] and av ariety of compartmentalized biochemical reactions. [6] The cell-free regulation of nicotinamide adenine nucleotide (NAD) coenzymes has been an important target in photocatalysis and functional module design. [7] In cells, NAD coenzymes controlt he flow of electrons in numerous redox transformations involvingo xidoreductases and are key components for the conversion and storageo fe nergy during photosynthesis. Therefore, the ability to control the redox state of NAD in a functional module offers aw ay to simplify and optimize the use of numerous enzymatic redox transformations,m any of them with relevant synthetic applications. [8] Previous work in this area has focused mainly on creating NAD modules containing inorganic photocatalysts, such as TiO 2 and other metal-based nanoparticles, encapsulatedi nt he lumen of lipid vesicles or embedded in solid matrices. [9] To date, most developmentsi nt his area has focusedo nr egenerating NADH through the photocatalytic reduction of NAD + . These metal-based catalysts show high versatility,s electivity, and excellent photocatalytic properties, but they can also suffer from the need for mediators or excitation wavelengths in the UV region, whichc an be harmful to other components in the system.Herein, we report the designo fametal-free, polymer-based NAD module that regenerates NAD + through the nonenzymatic photocatalytic oxidation of NADH by using visiblel ight. Our photocatalyst consisted of conjugated microporous polymer nano...