Table 1
pH values of the different mixtures
Entry	1	2	3	4	5	6	7
NaOH (μL)	35	70	105	140	175	210	245
pH	7.73	8.45	9.01	9.28	9.57	9.69	9.75

Each assay contained 4 mL of sodium citrate (10⁻³M), 0.35 mL of AgNO₃ (5.10⁻³M), 0.15 mL of NaBH₄ (10⁻²M) and, from 1 to 7, increasing volumes of freshly made 1 M NaOH

Drogat et al. Nanoscale Research Letters 2009 5:566   doi:10.1186/1556-276X-5-566