For efficient tandem catalysis, both catalysts -in this case, nanoparticles and the enzyme -must operate effectively under similar conditions. Based on a previous study, we selected our recently developed Au/CaO catalyst due to its demonstrated ability to oxidize a wide range of aliphatic alcohols into the corresponding carboxylic acids with yields exceeding 95 % within 24 h (10 mM scale) in several enzyme-compatible buffers, including the MOPS, which was used for the ACL screening. However, the compatibility of this catalyst with ACL operating conditions, particularly its ability to function in the presence of the cofactors such as Mg or Mn, had not yet been fully established. Therefore, we investigated the influence of buffer type and pH on the activity of the Au/CaO catalyst in the presence of 5 mM cofactor at 60 °C. Although if we previously observed complete inhibition of the catalyst in TRIS-HCl, we decided to retain this buffer in the study because the metal cofactor might provide a protective effect. We varied the pH of each buffer according to its capacity, to resolve a range from 8 to 11 (MOPS pH 8-9, TRIS-HCl pH 9-10, CAPS pH 10-11). It should be noted that the screening of different buffers was carried out only with the addition of Mg, at the exception of MOPS pH 8, which was also tested in the presence of 5 mM Mn and a Mg/Mn mixture, both at a concentration of 5 mM, to test the influence of the nature of the metal cation. Finally, butanol (1a) was chosen as model substrate for this screening thank to its high solubility in buffers. The results are shown in Table .