In vitro investigations of smart drug delivery systems based on redox-sensitive cross-linked micelles.

Redox-sensitive micelles are designed by using block copolymers of different architectures composed of a hydrophilic block of poly(ethylene oxide), and hydrophobic blocks of poly(ϵ-caprolactone) and poly(α-azide-ϵ-caprolactone). Stability of these micelles is insured in diluted media by cross-linking their core via the addition of a bifunctional cross-linker, while redox sensitivity is provided to these micelles by inserting a disulfide bridge in the cross-linker. The potential of these responsive micelles to be used as nanocarriers is studied in terms of cytotoxicity and cellular internalization. The release profiles are also investigated by varying the environment reductive strength.