Angewandte Chemie Biosensors DOI: 10.1002/ange.200902090 Immediate Detection of Living Bacteria at Ultralow Concentrations Using a Carbon Nanotube Based Potentiometric Aptasensor** Gustavo A. Zelada-GuillØn, Jordi Riu,* Ali Düzgün, and F. Xavier Rius* Zuschriften 7470 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Angew. Chem. 2009, 121, 7470 –7473