To obtain AuNPs with a diameter of 43 nm, 80 ml of an aqueous solution of 0.1 M CTAC are added to 4.8 ml of 0.01M AA together with 798 µl of the 10 nm AuNP seed solution in a roundbottom flask and kept at 27 °C. Subsequently, 80 ml of 0.5 mM HAuCl4 are added drop-wise while stirring with a syringe pump at a rate of 80 ml/h. After the HAuCl4 addition, the solution is left to stir for another 15 minutes. The solution is then centrifuged at 5000 rpm for 15 minutes and the final product was redispersed in water and diluted to an OD of 13, as confirmed using extinction spectroscopy. For AuNPs with a diameter of 43 nm, an OD of 13 corresponds to a density of ~6.31×10 11 AuNPs/ml. To synthesize 25 nm, 69 nm and 79 nm AuNPs the same procedure is being following with 4000 µl, 40 µl and 27 µl of the 10 nm AuNP seed solution, respectively.