Elucidating the underlying mechanisms of cell physiology is currently an important research topic in life sciences. Atomic force microscopy methods can be used to investigate these molecular mechanisms. In this study, single-molecule force spectroscopy was used to explore the specific recognition between the CD20 antigen and anti-CD20 antibody Rituximab on B lymphoma cells under near-physiological conditions. The CD20-Rituximab specific binding force was measured through tip functionalization. Distribution of CD20 on the B lymphoma cells was visualized three-dimensionally. In addition, the relationship between the intramolecular force and the molecular extension of the CD20-Rituximab complex was analyzed under an external force. These results facilitate further investigation of the mechanism of Rituximab’s anti-cancer effect.
LI MiLIU LianQingXI NingWANG YueChaoDONG ZaiLiLI GuangYongXIAO XiuBinZHANG WeiJing
The observation of friction anisotropy on graphene by friction measurement at atomic scale has been reported in this paper.Atomic-scale friction measurement revealed friction anisotropy with a periodicity of 60°,which is consistent with the hexagonal periodicity of the graphene.Both experiments and theory show that the value of the friction force is related to the graphene lattice orientation,and the friction force along armchair orientation is also larger than the one along zigzag orientation.These results will play a critical role in the use of graphene to manufacture nanoscale devices.
ZHANG YuLIU LianQingXI NingWANG YueChaoDONG ZaiLiWEJINYA Uchechukwu C
