ChemComm
DOI: 10.1039/C5CC01P53a2gDe 4 of 4
The enantioselective uptake by the polymer could also be
operation of enantioselective separation and sensing with wide
confirmed by analyzing dry polymer containing adsorbed
substrate that was filtered from the separation process. The
absorption spectra (in DMSO) had peaks of the substrate along
with the polymer (supporting figure S11) indicating the uptake of
the substrates. The 1H NMR spectra (in DMSO-d6) of the
PFGAP+phenylalanine showed the broadening of the entire
applicability.
60
TS thanks financial support by the Science & Engineering
Research Board funded project SB/S1/OC-66/2013. The authors
would like to thank Dr. H. N. Gopi, IISER Pune for circular
dichroism spectrometer facility. TSK thanks Raja Ambal for the
useful discussions during the progress of the work. The authors
5
aromatic region confirming interaction between the polymer and 65 also thank Dr. Paresh Dhepe, Dr. C. V. V Satyanarayana and Dr.
substrate, unlike a simple physical mixture where the peak shape
Shubhangi B Umbarkar for HPLC measurements.
10 would not be affected. Thermogravimetric analysis (TGA) of PF-
GAP+Phenylalanine showed a higher (> 5 wt %) weight loss than
pristine polymer indicating loss of adsorbed material. The DSC
Notes and references
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thermogram exhibited
a lowering of the glass transition
temperature upon uptake of substrate (see detailed description
15 and respective figures in supporting information S11-14). All
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25 dissolves-like’ rule. Unlike a membrane based separation where
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35 the substrate and the appendage unit. The degree of enhancement
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the extent of non-covalent interactions with the homochiral
polymer channels. The amplification of chirality demonstrated
here proved the potential of PF-GAP polymer as an effective
40 enantioselective separation media for racemic mixtures.
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50 and aromatic drug in water was successfully accomplished using
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Enantioselectively adsorbed substrates lead to an amplification of
55 chirality with the highest value of 11-fold enhancement based on
the ‘Sergeant Soldier principle’. This work demonstrates a very
efficient design of a biomimetic polymer probe for the combined
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