A novel procedure for immobilization of liposomes inside fused-silica capillaries is demonstrated. First, the inner wall of the capillaries was coated with a positively charged polymer, composed of derivatized agarose. Subsequently, negatively charged liposomes were immobilized by electrostatic interaction on the polymer coating. The developed liposome coated capillaries were used as a nanoseparation tool for studying interactions between small drug compounds and liposomes. Part of this work was presented at the 15th International Symposium on Microscale Separations and Analysis, HPCE 2002, Stockholm, Sweden, April 2002.