According to the present invention, a composite material having a combination of a carrier and a physiologically active substance, which can be obtained conveniently and excellent in the integrated efficiency of the bioactive substance, and has a good membrane breaking function promoting effect, is provided. In the complex according to the present invention, a bioactive substance is carried on an aggregates of a pH sensitive carrier agglomerated under acidic conditions.本発明によれば、簡便に得られ、生理活性物質の一体化効率に優れ、かつ良好な膜破壊機能促進効果を有する、キャリアと生理活性物質とが一体化した複合体が提供される。本発明に係る複合体は、酸性下で凝集してなるｐＨ感受性担体の凝集体に、生理活性物質が担持されてなる。
