Jump to main content
Jump to site search

Issue 75, 2016, Issue in Progress
Previous Article Next Article

pH responsive highly branched poly(N-isopropylacrylamide) with trihistidine or acid chain ends

Author affiliations

Abstract

Thermally responsive highly branched poly(N-isopropyl acrylamide)s (HB-PNIPAM) were prepared and end-functionalised to give polymers with acid or trihistidine end groups. These polymers exhibit a broad coil-to-globule transition across a wide temperature range which can be measured using covalently attached fluorescent tags. The acid chain ends provided a material with a distinct change in solution behaviour at pH close to the pKa of the carboxylate group. At pH 11 this polymer did not show a cloud point up to 50 °C but fluorescence measurements on the labelled polymers showed that a coil to globule transition did take place. The globular state, above the LCST, appeared to be more swollen if the end group carried charge then when it was uncharged. A polymer with trihistidine and free carboxylate chain ends, which contained multiple charges at various pH, did show LCSTs at all pH and the polymer globule was shown to be swollen at each pH.

Graphical abstract: pH responsive highly branched poly(N-isopropylacrylamide) with trihistidine or acid chain ends

Back to tab navigation

Supplementary files

Publication details

The article was received on 20 May 2016, accepted on 06 Jul 2016 and first published on 19 Jul 2016


Article type: Paper
DOI: 10.1039/C6RA13139E
Author version
available:
Download author version (PDF)
Citation: RSC Adv., 2016,6, 71345-71350
  •   Request permissions

    pH responsive highly branched poly(N-isopropylacrylamide) with trihistidine or acid chain ends

    T. Swift, J. Lapworth, K. Swindells, L. Swanson and S. Rimmer, RSC Adv., 2016, 6, 71345
    DOI: 10.1039/C6RA13139E

Search articles by author

Spotlight

Advertisements