Previous studies show that mixing ethanol and methanol lead to a certain degree of size control in the range 10-30 nm (larger NPs are obtained when the methanol content increases) . Tuning the concentration of NaOH and/or the wavelength of the light used during synthesis can also lead to size control . Larger NPs are obtained when the NaOH/Au molar ratio deviates from 4 (higher and smaller molar ratios lead to larger NPs). Smaller NPs are obtained with lights of lower wavelengths. None of these strategies are ideal since they use relatively toxic chemicals (methanol) or do not lead to a fine size control and/or required specific equipment (e.g. lights with specific wavelengths).