Figure 5.

A) In vitro cellular uptake study of the UCNP-based theranostic micelles in NET (TT) cells. Cells were treated with pure medium (i.e., control), nontargeted (i.e., lacking KE108) micelles, and targeted (i.e., KE108-conjugated) micelles (166 μg mL⁻¹), as well as the combination of free KE108 peptide (2 × 10⁻⁶ M) and targeted micelles (i.e., blocking) for 2 h at 37 °C. Images were taken under a multiphoton microscope based on the 650 nm luminescence emission of the NIR-activated UCNPs (Ex/Em: 980/650 nm). B) In vitro evaluation of cell viabilities. Abbreviation for all treatment groups was summarized in Table 1. For all laser-related treatments, the cells were first incubated with micelles for 3 h, followed by irradiation by the 980 nm laser at a power density of 0.5 W cm⁻² for 10 min. The cells were then incubated at 37 °C for another 45 h. *: p < 0.05; **: p < 0.01; ***: p < 0.001.