Reduction-Responsive Sheddable Carbon Nanotubes Dispersed in Aqueous Solution.

A new approach to stabilize carbon nanotubes (CNTs) in aqueous solution with a reduction-responsive water-soluble polymer is reported. The novel polymer synthesized by a controlled radical polymerization is functionalized with pendant pyrene groups capable of adhering to the surface of CNTs through π-π noncovalent interactions, and labeled with disulfide linkages to exhibit reduction-responsive cleavage. Upon the cleavage of junction disulfide linkages in a reducing environment, water-soluble polymers are shed, retaining clean CNT surfaces for electrochemical catalytic reactions.

Reductively-sheddable cationic nanocarriers for dual chemotherapy and gene therapy with enhanced release.

The development of a versatile strategy to synthesize cationic nanocarriers capable of co-delivery and enhanced release of drugs and oligonucleotides is promising for synergic dual chemotherapy and gene therapy. Herein, we report a novel cationic amphiphilic diblock copolymer having a single reduction-responsive disulfide linkage at a junction between a FDA-approved polylactide (PLA) block and a cationic methacrylate block (C-ssABP). The amphiphilic design of the C-ssABP enables the formation of cationic micellar aggregates possessing hydrophobic PLA cores, encapsulating anticancer drugs; cationic coronas, ensuring complementary complexation with negatively-charged oligonucleotides through electrostatic interactions; and disulfides at interfaces, leading to enhanced release of both encapsulated drugs and complexed oligonucleotides. The reduction-responsive intracellular trafficking results from flow cytometry, confocal laser scanning microscopy, and cell viability, as well as in vitro gene transfection assay suggest that C-ssABP offers versatility as an effective nanocarrier platform for dual chemotherapy and gene therapy.