Long-circulation zwitterionic dendrimer nanodrugs for phototherapy of tumors.

The development of stealth and effective antitumor nanodrugs has been drawing great attention. Herein, generation five poly(amide amine) dendrimer (G5 PAMAM) was modified by zwitterionic material carboxybetaine methacrylamide (CBMAA) on its surface to prepare zwitterionic dendrimer (G5-CBMAA). The results showed that G5-CBMAA had the longest blood circulation time due to its thickest zwitterionic layer, and its residual rate after injection into mice at 2 and 12 h was as high as 47.22 % and 14.37 %, respectively. Nanodrug G5-CBMAA-ICG was prepared by containing indocyanine green (ICG) in the cavity of G5-CBMAA. G5-CBMAA-ICG had better tumor targeting ability and antitumor effect than free ICG in mice after laser irradiation, and the tumor inhibition rate was 96.6 % after 14 days' treatment. The prepared G5-CBMAA-ICG has great potential applications in the field of antitumor by phototherapy.