The invention discloses the nanoparticles composed of chitosan, poly-γ-glutamic acid, and at least one bioactive agent characterized with a positive surface charge and their enhanced permeability for paracellular drug delivery.由甲殼素、聚-γ-GA、至少一種以上之生物活性藥物所組成之正電奈米顆粒,可促進特殊藥物群之遞送效率。