Biological Atomic Force Microscopy for Imaging Gold-Labeled Liposomes on Human Coronary Artery Endothelial Cells
Figure 4
AFM images ((a), (c), and (e)) and corresponding fluorescence images ((b), (d), and (f)) of HCAECs incubated for 15 ((a) and (b)), 60 ((c) and (d)), and 120 min ((e) and (f)) with FITC-labeled liposomes conjugated with 90 nm gold particles. The cells with positive signaling in the bright field images (squares in the right-hand panels) were selected for AFM scanning. (a) Typical AFM image of an HCAEC incubated for 15 min, showing a gold liposome cluster attached to the cell membrane. (c) AFM image demonstrating the internalization process occurring in an HCAEC incubated for 60 min with “gold liposomes.” (e) The AFM micrograph of an HCAEC incubated for 120 min corroborated that the “gold liposomes” internalized almost completely at this time point. Cells fixed in formalin 10% and scanned in contact mode in liquid (DNP-S = 12–24 kHz, N/m).
