Hyperbranched poly(amidoamine)s with methyl ester terminals (HPAMAM) were synthesized by one-pot approach and subsequently used as nanoreactors to prepare CdS quantum dots (QDs). HPAMAM could bind Cd(2+) through their internal amines, while the external methyl ester groups prevented the aggregation of polymers. After reaction with S(2-), CdS QDs sequestered within individual hyperbranched polymers were obtained. The resulting CdS/HPAMAM nanocomposites were characterized by dynamic light scattering, transmission electron microscopy, ultraviolet-visible spectroscopy, photoluminescence spectroscopy, and Fourier transform infrared spectroscopy, confirming the formation of CdS QDs with small particle size and narrow size-distribution. Furthermore, the effects of Cd(2+)/S(2-) ratio and aging time on the photoluminescence of CdS QDs were also investigated. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 1077-1083, 2011