This paper studies self-assembly of p-cyclodextrin (3-CD) and tri-block pluronic (PEG-PPG-PEG) in aqueous solution. It was found that they could form hollow spheres due to the formation of coil-rod beta-CD/PEG-PPG-PEG inclusion complexes. In these beta-CD/PEG-PPG-PEG complexes, the beta-CDs are preferentially stacked along the PPG block of pluronic to form rod block and PEG segments act as coil block. The assemblies of beta-CD/PEG-PPG-PEG complexes show dependence of beta-CDs concentration and temperature. Furthermore, the aggregates will disrupt upon dilution below the critical micelle concentration. (C) 2010 Elsevier Inc. All rights reserved.