ERBB2 and breast carcinoma: Click functionalization of the maleimide groups with anti-HER2 affibody (for 14 and 15 based CPNPs) or human immunodeficiency virus type 1 (HIV-1) trans-activating transcriptional activator (Tat, for 16 based CPNPs) was performed to increase the HER2-overexpressed SKBR-3 breast cancer cell (CPNP14 and CPNP15) or HepG2 liver cancer cell (for CPNP16) internalization efficiency compared to the non-functionalized CPNPs.