Fig. 4.

Influence of different factors on EE of GNPs. Different quantities of polyelectrolyte (PSS/PAH) used for GNP preparation and different quantities of GNPs (with two polyelectrolyte layers) incubated at pH 4 for four h (A), GNPs (25 mg) with different number of layers and incubation time at pH 4 (B) and GNPs (25 mg) with six polyelectrolyte layers incubated for four h at different pH (C). Means followed by the same latter in each GNP type are not significantly different at P ≤ 0. 05 according to DMRT