Preparing high photoluminescent carbon nanodots (CNDs) by facile and low-cost processes have received considerable research interest. In this paper, high photoluminescent nitrogen-containing CNDs have been synthesized by one-step hydrothermal treatment of the pipe tobacco. The dispersion of these CNDs shows a strong blue luminescent emission with a max peak at 450 nm when it is excited at 369 nm. The as-made CNDs can sensitively and selectively detect Cu2+ ions compared with Ca2+, Mn2+, Zn2+, Cd2+, Pb2+ ions, which offers a novel sensing platform for the detection of Cu2+ ions. (C) 2012 Elsevier Ltd. All rights reserved.