Morphological analysis
The samples (μL) were drop-casted on a clean silicon wafer (10 mm × 10 mm) for the analysis of their morphology. The samples were first concentrated using a centricon filter and then diluted about 100 folds using Milli-Q water. The casted samples were then left inside the laminar air flow for about 2-3 hrs for removing the moisture. These dried samples were scanned in non-contact mode using an Oxford Asylum Atomic force microscope (Oxford, Asylum) equipped with a silicon nitride tip (Elofsson et al. 1997)
All the experiments were performed in triplicates and their mean ± standard deviation data are presented.