16 Interactions Between Carbon-Based Nanostructures and Biomembranes. . .
283
Fig. 16.6 The average force required to insert graphene sheet into bilayer
16.3.4 Indentation with Graphene Sheet
The results shown in Fig. 16.6 were obtained for 56 Å width and 32 Å height
graphene sheet which pierced the bilayer with speed equal to 2 m/s. Note that in
case of this part of our studies, the springs were added to the carbon atoms closest
to the membrane. The shape of force plot is similar to the curves obtained for other
discussed systems. At the first part of diagram, the force required for the indentation
process grows. The maximum force is about 2.5 nN, and it is connected with the
region where graphene sheet presses apart the glycerol backbones or hydrocarbon
tails of phospholipids (between 12 and 16 Å). Next, the force starts to diminish.
16.3.5 Extraction and Self-Sealing Processes
The last part of our studies was performed for open-ended (10, 10) CNT. The
pulling speed was equal to 1.5 m/s. Figure 16.7 shows the average force required
for extraction process. This chart should be analyzed from right to left.
The average force required to pull CNT out of the membrane is significantly
lower comparing to the nanoindentation process (see Fig. 16.3). After the initial
part of extraction, where the force grows to, approximately, 0.5 nN, the maximum
width can be observed. It is wider compared to the indentation example, because the
opposite to deflection process occurs and, firstly, CNT overcomes the deflection and,
next, it “raises” whole membrane up. At the last part of extraction process, where
the membrane is not able to accommodate changes caused by nanotube, CNT starts
to leave the membrane definitely, and the force starts to diminish.
283
Fig. 16.6 The average force required to insert graphene sheet into bilayer
16.3.4 Indentation with Graphene Sheet
The results shown in Fig. 16.6 were obtained for 56 Å width and 32 Å height
graphene sheet which pierced the bilayer with speed equal to 2 m/s. Note that in
case of this part of our studies, the springs were added to the carbon atoms closest
to the membrane. The shape of force plot is similar to the curves obtained for other
discussed systems. At the first part of diagram, the force required for the indentation
process grows. The maximum force is about 2.5 nN, and it is connected with the
region where graphene sheet presses apart the glycerol backbones or hydrocarbon
tails of phospholipids (between 12 and 16 Å). Next, the force starts to diminish.
16.3.5 Extraction and Self-Sealing Processes
The last part of our studies was performed for open-ended (10, 10) CNT. The
pulling speed was equal to 1.5 m/s. Figure 16.7 shows the average force required
for extraction process. This chart should be analyzed from right to left.
The average force required to pull CNT out of the membrane is significantly
lower comparing to the nanoindentation process (see Fig. 16.3). After the initial
part of extraction, where the force grows to, approximately, 0.5 nN, the maximum
width can be observed. It is wider compared to the indentation example, because the
opposite to deflection process occurs and, firstly, CNT overcomes the deflection and,
next, it “raises” whole membrane up. At the last part of extraction process, where
the membrane is not able to accommodate changes caused by nanotube, CNT starts
to leave the membrane definitely, and the force starts to diminish.