Ultra-high resolution imaging of DNA and nucleosomes using non-contact atomic force microscopy.

Atomic force microscopy of chromatin arrays reveal non-monotonic salt dependence of array compaction in solution

Compaction of DNA in chromatin is a hallmark of the eukaryotic cell and unravelling its structure is required for an understanding of DNA involving processes. Despite strong experimental efforts, many questions concerning the DNA packing are open. In particular, it is heavily debated whether an ordered structure referred to as the "30 nm fibre" exist in vivo. Scanning probe microscopy has becom...

Breaking the speed limit with atomic force microscopy

High-speed atomic force microscopy (AFM) is important for following processes that occur on sub-second timescales for studies both in biology and materials science, and also for the ability to examine large areas of a specimen at high resolution in a practical length of time. Further developments of the previously reported high-speed contact-mode AFM are described. Two instruments are presented...

Dynamics of nucleosomes assessed with time-lapse high-speed atomic force microscopy.

A fundamental challenge of gene regulation is the accessibility of DNA within nucleosomes. Recent studies performed by various techniques, including single-molecule approaches, led to the realization that nucleosomes are quite dynamic rather than static systems, as they were once considered. Direct data are needed to characterize the dynamics of nucleosomes. Specifically, if nucleosomes are dyn...

High Resolution Image with Multi-wall Carbon Nanotube Atomic Force Microscopy Tip (RESEARCH NOTE)

In this paper, a simple and reproducible approach for attaching the multi-wall carbon nanotubes (MWNTs) to the apex of the atomic force microscope probe has been proposed. For this purpose, the dielectrophoresis method was applied due to its simple performance, cheapness and reliability. In this method, various parameters such as voltage, frequency, concentration of carbon nanotubes solution an...

Stability, resolution, and ultra-low wear amplitude modulation atomic force microscopy of DNA: Small amplitude small set-point imaging