TY - JOUR
T1 - Hidden Components in Aqueous "gold-144" Fractionated by PAGE
T2 - High-Resolution Orbitrap ESI-MS Identifies the Gold-102 and Higher All-Aromatic Au-pMBA Cluster Compounds
AU - Alvarez, Marcos M.
AU - Chen, Jenny
AU - Plascencia-Villa, Germán
AU - Black, David M.
AU - Griffith, Wendell P.
AU - Garzón, Ignacio L.
AU - José-Yacamán, Miguel
AU - Demeler, Borries
AU - Whetten, Robert L.
N1 - Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/7/7
Y1 - 2016/7/7
N2 - Experimental and theoretical evidence reveals the resilience and stability of the larger aqueous gold clusters protected with p-mercaptobenzoic acid ligands (pMBA) of composition Aun(pMBA)p or (n, p). The Au144(pMBA)60, (144, 60), or gold-144 aqueous gold cluster is considered special because of its high symmetry, abundance, and icosahedral structure as well as its many potential uses in material and biological sciences. Yet, to this date, direct confirmation of its precise composition and total structure remains elusive. Results presented here from characterization via high-resolution electrospray ionization mass spectrometry on an Orbitrap instrument confirm Au102(pMBA)44 at isotopic resolution. Further, what usually appears as a single band for (144, 60) in electrophoresis (PAGE) is shown to also contain the (130, 50), recently determined to have a truncated-decahedral structure, and a (137, 56) component in addition to the dominant (144, 60) compound of chiral-icosahedral structure. This finding is significant in that it reveals the existence of structures never before observed in all-aromatic water-soluble species while pointing out the path toward elucidation of the thermodynamic control of protected gold nanocrystal formation.
AB - Experimental and theoretical evidence reveals the resilience and stability of the larger aqueous gold clusters protected with p-mercaptobenzoic acid ligands (pMBA) of composition Aun(pMBA)p or (n, p). The Au144(pMBA)60, (144, 60), or gold-144 aqueous gold cluster is considered special because of its high symmetry, abundance, and icosahedral structure as well as its many potential uses in material and biological sciences. Yet, to this date, direct confirmation of its precise composition and total structure remains elusive. Results presented here from characterization via high-resolution electrospray ionization mass spectrometry on an Orbitrap instrument confirm Au102(pMBA)44 at isotopic resolution. Further, what usually appears as a single band for (144, 60) in electrophoresis (PAGE) is shown to also contain the (130, 50), recently determined to have a truncated-decahedral structure, and a (137, 56) component in addition to the dominant (144, 60) compound of chiral-icosahedral structure. This finding is significant in that it reveals the existence of structures never before observed in all-aromatic water-soluble species while pointing out the path toward elucidation of the thermodynamic control of protected gold nanocrystal formation.
UR - http://www.scopus.com/inward/record.url?scp=84978154117&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcb.6b04525
DO - 10.1021/acs.jpcb.6b04525
M3 - Article
C2 - 27275518
AN - SCOPUS:84978154117
SN - 1520-6106
VL - 120
SP - 6430
EP - 6438
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 26
ER -