Figure 1.

Uptake and accumulation levels of bare BPs and TiL4@BPs by raw 264.7 cells. a) Localization of bare BPs or TiL4@BPs (indicated with red arrow) associated with cells after 6 h exposure to 10 μg mL⁻¹ of bare BPs or TiL4@BPs determined using bright‐field microscopy. Red arrow shows the aggregated BPs within or associated cells. b) Raman mapping based on the intensity at 463.3 cm⁻¹ of the representative J774A.1 cell treated with bare BPs or TiL4@BPs at 10 μg mL⁻¹ for 24 h. The Raman spectra acquired from 4 different sites are also shown. c) Raman spectra of the center site of 25 randomly selected cells treated with bare BPs or TiL4@BPs, and their average Raman signal intensities at 463.3 cm⁻¹ are calculated to determine their cell uptake levels. *p<0.05.