Size‐Controlled Formation of a Calcium Phosphate‐Based Organic–Inorganic Hybrid Vector for Gene Delivery Using Poly(ethylene glycol)‐block‐poly(aspartic acid)

Abstract
Poly(ethylene glycol) (PEG)‐covered hybrid particles (see Figure) of calcium phosphate (CaP), and plasmid DNA (pDNA) have been prepared in a size‐controllable manner in the presence of a block copolymer. The particles show a substantial colloidal stability as well as tolerance of entrapped pDNA against nuclease attack in the medium, and achieve a significantly higher gene expression compared to conventional precipitates.