Electrospray ionization mass spectrometry of intrinsically cationized nanoparticles, [Au(144/146)(SC(11)H(22)N(CH(2)CH(3))(3)(+))(x)(S(CH(2))(5)CH(3))(y)](x+).
Electrospray ionization triple-quadrupole mass spectrometry of ca. 1.6 nm diameter thiolate-protected gold nanoparticles has been achieved at higher resolution than in previous reports. The results reveal the presence of nanoparticles with formulas Au(144)L(60) and Au(146)L(59), present in the sample as a mixture. The improved resolution is based on lowering m/z by exchanging multiple [-SC(11)H(22)N(CH(2)CH(3))(3)(+)] ligands into the original [-S(CH(2))(5)CH(3)] ligand shell. The nanoparticles are thus intrinsically cationized and appear as a series of 10+ to 15+ mass spectral peaks. The assigned state of charge was confirmed by a collision-induced dissociation measurement.
Kenan Laboratories of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
Christina A
CA
Fields-Zinna
Rajesh
R
Sardar
Christopher A
CA
Beasley
Royce W
RW
Murray
D002412:Cations; D006046:Gold; D053768:Metal Nanoparticles / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D002412:Cations; D006046:Gold