Relative surface charge density mapping with the atomic force microscope
Relative surface charge density mapping with the atomic force microscope
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DOI：
10.1016/s0006-3495(99)77221-8
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发表时间：
1999-01-01
影响因子：
3.4
通讯作者：
Hoh, JH
中科院分区：
文献类型：
--
作者：
Heinz, WF;Hoh, JH
提出了一种利用原子力显微镜制作生物表面相对电荷密度图的实验方法。这种方法被称为D-D （D-D）映射，它使用在不同盐浓度下收集的等力表面来去除地形并隔离静电对尖端-样品相互作用力的贡献。这种方法对低于25 mV的表面电位是定量的，并且不需要事先知道悬臂弹簧常数、尖端半径或尖端电荷。此外，D-D映射不需要尖端样品接触。D-D映射的性能在恒定电荷和不同地形的表面（机械粗糙的云母和堆叠的双棕榈酰磷脂酰丝氨酸双层）、变化电荷和不同地形的表面（云母上的双棕榈酰磷脂酰胆碱斑块）和吸附在云母上的细菌hopsin膜上得到了证明。
An experimental approach for producing relative charge density maps of biological surfaces using the atomic force microscope is presented. This approach, called D minus D (D-D) mapping, uses isoforce surfaces collected at different salt concentrations to remove topography and isolate electrostatic contributions to the tip-sample interaction force. This approach is quantitative for surface potentials below 25 mV, and does not require prior knowledge of the cantilever spring constant, tip radius, or tip charge. In addition, D-D mapping does not require tip-sample contact. The performance of D-D mapping is demonstrated on surfaces of constant charge and varying topography (mechanically roughened mica and stacked bilayers of dipalmitolphosphatidylserine), a surface of varying charge and varying topography (patches of dipalmitolphosphatidylcholine on mica), and bacteriorhopsin membranes adsorbed to mica.