Robust Construction of Supersmall Zwitterionic Micelles Based on Hyperbranched Polycarbonates Mediates High Tumor Accumulation.

Despite the numerous advantages of nanomedicines, their therapeutic efficacy is hampered by biological barriers, including fast clearance, poor tumor accumulation, inefficient penetration, and cellular uptake. Herein, cross-linked supersmall micelles based on zwitterionic hyperbranched polycarbonates can overcome these challenges for efficiently targeted drug delivery. Biodegradable acryloyl/zwitterion-functionalized hyperbranched polycarbonates are synthesized by a one-pot sequential reaction of Michael-type addition and ring-opening polymerization, followed by controlled modification with carboxybetaine thiol.

Theoretical investigation of the tunable behavior of p-n copolymers based on oligothiophenes and 1,4-bis(oxadiazolyl)-benzene.

Semiempirical calculations were carried out on several model oligomers to investigate the tunable behavior of p-n copolymers with the repeating units constructed by oligothiophenes as the pi-excessive type blocks and 1,4-bis(oxadiazolyl) benzene as the pi-deficient type block. The calculated evolutions of the HOMO and LUMO of the model oligomers were in good agreement with the experimental oxidation and reduction potentials of the corresponding polymers. The effect of the length of the oligothiophene on the electronic structures and optical properties was elucidated by analyzing the HOMO and LUMO spatial distribution patterns of the model oligomers.