1 A highly pH-sensitive Zn(II) chemosensor Carla Bazzicalupi, Andrea Bencini, Silvia Biagini, Enrico Faggi, Giovanna Farruggia, Giulia Andreani, Paola Gratteri, Luca Prodi, Alessio Spepi, Barbara Valtancoli Electronic Supporting Information Page2____________________ Experimental details for H 2 L Page 3. Figure S1__________ Absorption spectra of 2’,7’-dichlorofluorescein in aqueous solution at different pH values Page 3. Figure S2__________ Fluorescence emission spectra of 2’,7’-dichlorofluorescein in aqueous solution at different pH values Page 4. Figure S3__________ Minimized conformations of [CdL(H 2 O)] complex. Page 5. Figure S4__________ pH dependence of the absorbance at 505 nm (Cd(II), Pb(II)) or 498 nm (Cu(II)) as a function of pH compared to the distribution curves of the complexes for a system containing H 2 L and Cd(II) (a) Pb(II) (b) or Cu(II) (c) in 1:1 molar ratio Page 6. Figure S5__________ ESI mass spectra recorded on a aqueous solution containing H 2 L and Zn(II) in 1:1 (a) and 1:2 (b) molar ratios. Page 7. Figure S6__________ Fluorescence emission intensity at 525 nm as a function of pH compared to the distribution curves of the Cu(II) (a) or Pb(II) (b) complexes for systems containing H 2 L and Cu(II) or Pb(II) in 1:1 molar ratio Page 8. Figure S7__________ Flow cytometric evaluation of the intracellular fluorescence distribution in unstained HL60 cells, H 2 L incubated cells and H 2 L incubated, digitonin permeabilized cells. Supplementary Material (ESI) for Dalton Transactions This journal is © The Royal Society of Chemistry 2010