To avoid the critical problems of effective drugs not being carried to their targeted cancers and their quantity and location not being sensed in situ, this work presents a completely new innovative strategy to achieve both smart cancer targeting (SCT) and super-sensitive sensing (SSS), where one drug carrier works for effective drug loading and release. Herein, malignant melanoma treatment is used as an example of reliable detection and effective therapy. We report two characteristic dumbbell-like nano-micelles and spherical-like nano-micelles of hyaluronan induced by the Eu3+/Tb3+ complexes for effective drug loading and release, respectively. These special Eu3+/Tb3+-loaded nano-micelles (marked as ENM and TNM) have strong and sharp red/green luminescence that can sensitively detect the malignant melanoma drug dacarbazine through changes in fluorescence intensity. Cytotoxicity experiments confirmed that both ENM and TNM are not toxic to normal cells at very high concentrations of 4 mM. However, when loaded with cancer drugs (D-ENM and D-ENM), they both killed cancer cells with more than 40% efficacy at this concentration. The in vivo experiments confirmed that D-ENM and D-TNM can effectively target cancer cells in tissue and effectively impede cancer growth. The detection limits of ENM and TNM in sensing cancer drugs can reach 0.456 μg/mL and 0.139 μg/mL, respectively. Therefore, the reported Eu3+/Tb3+-induced hyaluronan nano-micelles (ENM and TNM) are distinguished carriers of this cancer drug and excellent in situ sensors, and they have highly therapeutic effects with extremely low toxicity to normal cells.
Keywords: detection; drug carriers; malignant melanoma; rare earth complexes.