Abstract: Objective · To investigate the modification of live cell membranes with cholesterol linked deoxyribonucleic acid (cholesterol-DNA). Methods · The suspension L1210 cells and adherent PC-12 cells were included. L1210 cells and PC-12 cells were divided into the experimental group (incubated with cholesterol-DNA) and the control group (treated with phosphate buffer saline), respectively. The fluorescence intensity of the cells in the two groups was obtained and the experimental group cells were three-dimensional reconstructedconfocal microscopy. The morphology of the cells in the experimental group was observedscanning electron microscopy (SEM). The effect of cholesterol-DNA modification on cell membrane fluidity was detectedfluorescence recovery after photobleaching. Results · The results of suspension cells and adherent cells were consistent. Compared with the control group, the fluorescence intensity of cell surface in the experimental group was increased (both P0.000). Three-dimensional reconstruction of confocal microscopy showed that the fluorescence of the cells in the experimental group was distributed across the surface of the global cell. SEM showed that the morphology of the cells in the experimental group did not change with cholesterol-DNA modification. After fluorescence photobleaching, the relative fluorescence intensity of the L1210 cells in the experimental group was decreased to 0.090, and then recovered to 0.860 within 110 s. Conclusion · Cholesterol-DNA can modify the whole live cell membranes, and the modified cell membranes still have fluidity. This method can modify not only the suspension cells, but also the adherent cells.

Key words: cholesterol, deoxyribonucleic acid (DNA), cell membrane, modification