Synthesis of Degradable Organic Nanotubes by Bottlebrush Molecular Templating

Degradable organic nanotubes were synthesized by a single-molecule templating of core-shell bottlebrush copolymers composed of an etchable inner block (polylactide) and a functional outer block (poly(styrene-co-maleic anhydride)). The pendant mercapto groups generated along the outer block chains by reacting the anhydride groups with cysteamine were oxidized to disulfide groups acting as degradable cross-linking units in the shell layer. Subsequent hydrolytic removal of the polyester inner core provided hollow organic nanotubes held together by disulfide groups as cross-linkers. The cleavage of disulfide linkers by reaction with dithiothreitol resulted in a complete disintegration of nanotube structures into small fragments.