Linear-dendritic ABA triblock copolymers containing PEG were used for transport the small guest molecules such as 5,7-dibromo-8-hydoxy quinoline, ibuprofen, and Congo red. Nanocarriers containing guest molecules were soluble in water and in some of the organic solvents. Encapsulated guest molecules were soluble in some of the solvents, which they cannot be solved in them solely, for example, chloroform is a very poor solvent for Congo red, but encapsulated Congo red by nanocarriers is soluble in chloroform. The linear-dendritic copolymers/guest molecule complexes were stable at room temperature for about 10 months; during this time, guest molecules did not release from linear-dendritic copolymers/guest molecule complexes. The controlled release of guest molecules from linear-dendritic copolymers/guest molecule complexes in vitro conditions also was investigated. (c) 2007 Wiley Periodicals, Inc.