A surface chemical analysis of 12 nm diameter gold nanoparticles (AuNPs) coated with polyethylene glycol (PEG)-11-mercaptoundecanoic acid (MUA) is performed by means X-ray photoelectron spectroscopy (XPS). For this purpose, the PEGMUA-coated AuNPs are deposited using two different deposition techniques, drop-casting or spin-coating, on a thin-film carbon substrate. The measurements show that pr...