NM syntheses are sensitive to various parameters and batch to batch variations are common . The present synthesis is relatively stable regarding the ethanol grade . To assess further the robustness of the present synthesis we compared three different HAuCl4 precursors (i, ii and iii, detailed in SI) from different suppliers. The results are detailed in SI. Batch to batch variations were observed and HAuCl4-i and HAuCl4-ii were selected for the present study. This leads to an additional sample C with a size of ca.