Enzymatically Triggered, Isothermally Responsive Polymers: Reprogramming Poly(oligoethylene glycols) To Respond to Phosphatase

Abstract

(2015) Enzymatically-triggered, isothermally responsive polymers : re-programming poly(oligoethylene glycols) to respond to phosphatase. Biomacromolecules . 71881. http://dx.doi.org/10.1021/acs.biomac.5b00929 Permanent WRAP url: http://wrap.warwick.ac.uk/71881 Copyright and reuse:The Warwick Research Archive Portal (WRAP) makes this work of researchers of the University of Warwick available open access under the following conditions. Copyright © and all moral rights to the version of the paper presented here belong to the individual author(s) and/or other copyright owners. To the extent reasonable and practicable the material made available in WRAP has been checked for eligibility before being made available.Copies of full items can be used for personal research or study, educational, or not-forprofit purposes without prior permission or charge. Provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way. Publisher's statement:"This document is the Accepted Manuscript version of a Published Work that appeared in final form in Biomacromelecules copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/acs.biomac.5b00929 see http://pubs.acs.org/page/policy/articlesonrequest/index.html]." A note on versions:The version presented here may differ from the published version or, version of record, if you wish to cite this item you are advised to consult the publisher's version. Please see the 'permanent WRAP url' above for details on accessing the published version and note that access may require a subscription. By fine-tuning the density of phosphate groups on the backbone, it was possible to induce an isothermal transition: A change in solubility triggered by removal of a small number of phosphate esters from the side chains activating the LCST-type response. As there was no temperature change involved, this serves as a model of a cell-instructed polymer response.Finally, it was found that both polymers were non cytotoxic against MCF-7 cells (at 1 mg.mL -1 ), which confirms promise for biomedical applications.3

The Dependence of the Cloud Point, Clearing Point, and Hysteresis of Poly(N-isopropylacrylamide) on Experimental Conditions: The Need for Standardization of Thermoresponsive Transition Determinations

“…As indicated by the data in Table S1 (Supporting Information), cloud point measurement by UV–vis spectroscopy, available in most of the laboratories worldwide, is by far the most frequently applied method for the determination of the phase transition temperature by measuring mainly the transmittance ( Tr ) as a function of temperature. The absorbance–temperature curves are also used for this purpose in much less cases . Looking at the data and the remarks in Table S1 (Supporting Information) indicates that the selection of the conditions for LCST determination is rather individualistic, independent of which method is used, and it is hard, if not impossible, to make acceptable comparison of not only the CST values but the conclusions based on these data as well.…”

Propagation of Enzyme‐Induced Surface Events inside Polymer Nanoassemblies for a Fast and Tunable Response

“…We observed concentration‐dependent release between ALP concentrations of 2.5 n m and 12.5 n m , and the percent release was invariant above 12.5 n m . Interestingly, the molecular release also saturated at 45 %, which was attributed to the capability of the pHEMA product to bind some of the guest molecules . This was further confirmed through the spectroscopic observation of significant perylene encapsulation in the pHEMA homopolymer (Figure S7).…”

“…We were pleased to observe the presence of pHEMA in both phases after the enzymatic reaction as it is a direct indication of the ALP‐induced supramolecular disassembly of the P1 assemblies. The presumed enzyme‐induced morphological transformation, accompanying the supramolecular disassembly of P1 assemblies, seems to be due to the limited solubility of pHEMA . At the beginning of the enzymatic reaction, the pHEMA concentration is low enough for the polymer to be soluble (observed as a size decrease in the first 30 min), while it starts to form large structures as its concentration builds up in the reaction mixture (Figure S8).…”

“…The susceptibility of the crosslinked assemblies towards ALP was monitored by 31 P NMR analysis as well as by DLS (Figures S11 and S12). The degree of dephosphorylation was further quantified by directly following the production of phosphate ions using a chromogenic assay (Figure C). We were pleased to find that the dephosphorylation rates were independent of whether the assemblies were crosslinked or not.…”

Bio-responsive smart polymers and biomedical applications

“…Kinases catalyze the transfer of phosphate groups to the substrate (phosphorylation), and phosphatases, which complementary to the kinase functions to remove phosphate groups from the substrate (dephosphorylation). This antagonistic interplay benefits the construction of reversible or dynamic responsible systems [29]. In addition, there are also some enzymes that act to catalyze the formation of covalent bonding (e.g.…”