2.2. Cytotoxicity of PEG-PTX NPs in microwells
PTX is a clinical anticancer drug and it can be used to treat a variety of tumors including nasopharyngeal carcinoma.[51-53] The chemotherapy effect of PTX and PEG-PTX NPs towards NPC43 cells was tested by thiazolyl blue tetrazolium bromide (MTT) assays. The cytotoxicity of PTX and PEG-PTX NPs was time- and concentration-dependent as shown in Figure. 2d. As time and concentration increased, the cell viability decreased after the NPC43 cells were treated with PTX or PEG-PTX NPs, which indicated that PEG-PTX NPs could be effective to treat NPC43 cells. When the treatment incubation time was 16 h, small molecule PTX was more toxic to NPC43 cells compared with PEG-PTX NPs because PTX possessed direct drug effect but PEG-PTX NPs required time to release PTX to cells. However, as incubation time was extended to 64 h, both PEG-PTX NPs and PTX possessed similar chemotherapy effect towards NPC43 cells, which meant PEG-PTX NPs was an effective anticancer nanomedicine.