“…For instance, Wang et al prepared gold nanoparticles capped by thiolates containing pyrrole units by the above way [8] since pyrrole unites would be oxidized by AuCl − 4 if they coexisted in the solution [9]. Other improved synthetic techniques include heating [10] and vapor treatments [11,12], etching [13,14] and annealing procedures [15] and solubility fractionation [16]. The separation and purity technologies constitute another important aspect of MPCs [17][18][19].…”