High Resolution DNA Imaging by Dynamic Atomic Force Microscopy: The Effect of the Substrate and Sample Preparation

2014 ◽  
Vol 1652 ◽  
Author(s):  
Tzu-Chieh Tang ◽  
Carlo A. Amadei ◽  
Matteo Chiesa
Keyword(s):  
Atomic Force Microscopy ◽  
Metal Ions ◽  
Physicochemical Characteristics ◽  
Temporal Variations ◽  
Point Of View ◽  
Ion Distribution ◽  
Nickel Ion ◽  
Force Microscopy ◽  
Atomic Force ◽  
Force Profile

ABSTRACTAdsorption of charged biomolecules onto atomically flat mica substrates is facilitated by the deposition of metal ions. Despite successfully acting as preferential anchoring sites, the presence of ions on the mica surface also changes its physicochemical characteristics something that is rarely quantified from a nanoscale point of view. In this study the nanoscale physicochemical properties of nickel-functionalized Muscovite mica are investigated by reconstructing the conservative force profile between an atomic force microscopy (AFM) tip and the surface. Various nickel ion concentrations (i.e. 1.0 mM to 20.0 mM) along with different incubation times (30 seconds and 5 minutes) are directly analyzed. Details in the spatial and temporal variations in surface properties due to the ion mediated adsorption of water are presented in details and in light of the binding efficiency of the metal ions. This insight benefits our understanding in the behavior of ion distribution that plays a crucial role in biomolecule imaging using AFM.

scholarly journals Observing Effects of Calcium/Magnesium Ions and pH Value on the Self-Assembly of Extracted Swine Tendon Collagen by Atomic Force Microscopy

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Xuan Song ◽  
Zhiwei Wang ◽  
Shiyu Tao ◽  
Guixia Li ◽  
Jie Zhu
Keyword(s):  
Atomic Force Microscopy ◽  
Metal Ions ◽  
Self Assembly ◽  
Food Packaging ◽  
Ph Value ◽  
The Self ◽  
Solution Ph ◽  
Collagen Concentration ◽  
Force Microscopy ◽  
Atomic Force

Self-assembly of extracted collagen from swine trotter tendon under different conditions was firstly observed using atomic force microscopy; then the effects of collagen concentration, pH value, and metal ions to the topography of the collagen assembly were analyzed with the height images and section analysis data. Collagen assembly under 0.1 M, 0.2 M, 0.3 M CaCl2, and MgCl2 solutions in different pH values showed significant differences (P < 0.05) in the topographical properties including height, width, and roughness. With the concentration being increased, the width of collagen decreased significantly (P < 0.05). The width of collagen fibers was first increased significantly (P < 0.05) and then decreased with the increasing of pH. The collagen was assembled with network structure on the mica in solution with Ca2+ ions. However, it had shown uniformed fibrous structure with Mg2+ ions on the new cleaved mica sheet. In addition, the width of collagen fibrous was 31~58 nm in solution with Mg2+ but 21~50 nm in Ca2+ solution. The self-assembly collagen displayed various potential abilities to construct fibers or membrane on mica surfaces with Ca2+ ions and Mg2+ irons. Besides, the result of collagen self-assembly had shown more relations among solution pH value, metal ions, and collagen molecular concentration, which will provide useful information on the control of collagen self-assembly in tissue engineering and food packaging engineering.

scholarly journals Polymer Inclusion Membranes (PIMs) Doped with Alkylimidazole and their Application in the Separation of Non-Ferrous Metal Ions

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1780 ◽  
Author(s):  
Radzyminska-Lenarcik ◽  
Ulewicz
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Metal Ions ◽  
Diffusion Rate ◽  
Ferrous Metal ◽  
Cellulose Triacetate ◽  
Force Microscopy ◽  
Atomic Force ◽  
Scanning Electron

The study involved the transport of zinc(II), cadmium(II), and nickel(II) ions from acidic aqueous solutions using polymer inclusion membranes (PIMs). PIMs consisted of cellulose triacetate (CTA) as a support; o-nitrophenyl pentyl ether (o-NPPE) as a plasticizer; and 1-octylimidazole (1), 1-octyl-2-methylimidazole (2), 1-octyl-4-methylimidazole (3), or 1-octyl-2,4-dimethylimidazole (4) as ion carriers. The membranes were characterized by means of atomic force microscopy (AFM) and scanning electron microscopy (SEM). The results show that Zn(II) and Cd(II) are effectively transported across PIMs, while Ni(II) transport is not effective. The rate of transport of metal ions across PIMs is determined by the diffusion rate of the M(II)–carrier complex across the membrane. The best result achieved for Zn(II) removal after 24 h was 95.5% for the ternary Zn(II)–Cd(II)–Ni(II) solution for PIM doped (4). For this membrane, the separation coefficients for Zn(II)/Cd(II), Zn(II)/Ni(II), and Cd(II)/Ni(II) were 2.8, 104.5, and 23.5, respectively. Additionally, the influence of basicity and structure of carrier molecules on transport kinetics was discussed.

scholarly journals Effects of metal ions on the self-assembly of chitosan molecules investigated with atomic force microscopy

2018 ◽  
Vol 21 (1) ◽  
pp. 1986-1994
Author(s):  
Zhiwei Wang ◽  
Shengying Fei ◽  
Weisha Kong ◽  
Qi Xiao ◽  
Jie Zhu
Keyword(s):  
Atomic Force Microscopy ◽  
Metal Ions ◽  
Self Assembly ◽  
The Self ◽  
Force Microscopy ◽  
Atomic Force

Force-Strain Curves Of Microcapsules With Atomic Force Microscopy

2004 ◽  
Vol 838 ◽  
Author(s):  
Eli Lansey ◽  
Fredy R. Zypman
Keyword(s):  
Atomic Force Microscopy ◽  
Indentation Depth ◽  
Point Of View ◽  
Classical Elasticity ◽  
Force Microscopy ◽  
Afm Indentation ◽  
Atomic Force ◽  
Atomic Interactions ◽  
Linear Effects ◽  
Classical Elasticity Theory

ABSTRACTWe develop an algorithm to measure elastic properties of microcapsules with Atomic Force Microscopy (AFM). The AFM is used as an indenter and presses down on a spherical microcapsule. We study the system from an atomic point of view (considering interactions between the atoms in the system via Equivalent Crystal Theory) and calculate the force produced by the system to balance the external AFM force. We plot this force as a function of the indentation depth, and from that curve we extract the interatomic parameters of ECT that are related with elastic constants. Our calculations model measurements of force-strain curves including non-linear effects. This is relevant as classical elasticity theory breaks down in the AFM indentation regime, when atomic interactions must be considered explicitly.

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