02128nas a2200181   4500008004100000022001400041245014000055210006900195260011000264300001200374490000600386520134500392100002101737700002001758700002501778700001701803856012601820       2016                        eng d  a2050-750X00aOrientation effect induced selective chelation of Fe2+ to a glutamic acid appended conjugated polymer for sensing and live cell imaging0 aOrientation effect induced selective chelation of Fe2 to a gluta  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcDEC  a299-3080 v43 a<p>Intracellular detection and imaging of labile iron(II) pools is very important in tracking physiological processes that demand new and rapid sensing probes. In this report, we present a water soluble polymer based probe for the fluorescence sensing and live cell imaging of labile Fe2+ ions with high selectivity for the first time. The polymer probe was based on conjugated polyfluorene which was appended with amino acid (L-glutamic acid). The biocompatibility of the polymer was confirmed from an MTT assay which demonstrated &gt;90% cell viability even at 300 mu g ml(-1) loading of polymers. Simple glutamic acid did not show selectivity towards any of the divalent ions. However, glutamic acid appended polyfluorene exhibited selective chelation to Fe2+ ions resulting in immediate sensing activity for Fe2+ ions in water and living cells with fluorescence turn-off response. The limit of detection of the PF-Ph-GA polymer probe was 46 (+/- 2) nM which indicated high sensitivity for Fe2+ over other ions reported in the literature. The polymer also exhibited improved sensing activity in the range of intracellular pH (5-9) which is advantageous in differentiating endogenous changes. The probe was successfully applied for the fluorescence imaging of intracellular and supplemented labile iron(II) pools in living HeLa cells.</p>1 aSenthilkumar, T.1 aParekh, Nimisha1 aNikama, Shrikant, B.1 aAsha, S., K.  uhttps://library.ncl.res.in/content/orientation-effect-induced-selective-chelation-fe2-glutamic-acid-appended-conjugated-0