S-1 Water Soluble Cruciforms: Response to Protons and Selected Metal Ions Supporting Information Juan Tolosa, Anthony J. Zucchero, and Uwe H. F. Bunz* School of Chemistry and Biochemistry, Georgia Institute of Technology, 770 State Street, Atlanta, GA 30332. Fax: 404-385-1795; Tel: 404-510-2443; E-mail: uwe.bunz@chemistry.gatech.edu Materials and Methods All chemicals were purchased from Aldrich Chemical, Acros, TCI America, or Fischer Scientific and used without purification unless otherwise specified. Column chromatography was performed using Standard Grade silica gel 60 Å, 32-63 μm (230 x 450 mesh) from Sorbent Technologies and the indicated eluent. Elution of cruciforms was readily monitored using a handheld UV lamp (365 nm). Melting points were obtained using a Mel-Temp apparatus fitted with a Fluke 51 K/J digital thermometer. All pH measurements were made using a calibrated VWR sympHony SP20 digital pH meter. All IR spectra were obtained using a Simadzu FTIR-8400s spectrometer. Unless otherwise specified, NMR spectra were recorded at 298 K on a Varian Mercury spectrometer (300 MHz). Chemical shifts are reported in parts per million (ppm), using residual solvent (chloroform-d) as an internal standard. Data Reported as follows: chemical shift, multiplicity (s = singlet, d = doublet, t = triplet, q = quartet, m = multiplet), coupling constant, and integration. Mass spectral analyses were provided by the Georgia Institute of Technology Mass Spectrometry Facility. All absorption spectra were collected using a Shimadzu UV-2401PC spectraphotometer. All emission spectra were acquired using a Shimadzu RF-5301PC spectrofluorophotometer. Lifetime data were collected using a Lifespec-ps (Edinburgh Instruments), pulsed diode laser (PicoQuant, 372 nm excitation), and PMT detector (Hamamatsu). Data were fit to single exponential decay so as to optimize chi-squared values. Quantum yields for cruciforms were measured using standard procedures 1 . In all cases, quinine sulfate was used as a standard and all solutions were purged with nitrogen prior to measurement.