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Title: Chiral Separation of rac-Propylene Oxide on Penicillamine Coated Gold NPs
The surfaces of chemically synthesized spherical gold NPs (Au-NPs) have been modified using chiral L- or D-penicillamine (Pen) in order to impart enantioselective adsorption properties. These chiral Au-NPs have been used to demonstrate enantioselective adsorption of racemic propylene oxide (PO) from aqueous solution. In the past we have studied enantioselective adsorption of racemic PO on L- or D-cysteine (Cys)-coated Au-NPs. This prior work suggested that adsorption of PO on Cys-coated Au-NPs equilibrates within an hour. In this work, we have studied the effect of time on the enantioselective adsorption of racemic PO from solution onto chiral Pen/Au-NPs. Enantioselective adsorption of PO on chiral Pen/Au-NPs is time-dependent but reaches a steady state after ~18 h at room temperature. More importantly, L- or D-Pen/Au-NPs are shown to adsorb R- or S-PO enantiospecifically and to separate the two PO enantiomers from racemic mixtures of RS-PO.  more » « less
Award ID(s):
1764252
PAR ID:
10224449
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Nanomaterials
Volume:
10
Issue:
9
ISSN:
2079-4991
Page Range / eLocation ID:
1716
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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