A novel conjugated cationic polyfluorene containing aminated tetraphenylethene (ATPE) unit is developed as a sensitive and selective fluorescence probe for heparin detection based on the combination of aggregation-induced emissive property of the ATPE units and the FRET process from the blue-emissive polyfluorene segments to the yellow-emissive AWE units. The addition of anionic heparin will lead to the formation of heparin/polymer complexes, and turn on the aggregation-induced yellow emission of the ATPE units. A good linear relationship is found between the yellow emission intensity of the AWE units and the heparin concentrations with a limit of detection of 30 nM in aqueous buffer. (C) 2011 Elsevier Ltd. All rights reserved.