Unusually high bending flexibility has been recently reported for DNA on short length scales. We use atomic force microscopy (AFM) in solution to obtain a direct estimate of DNA bending statistics for scales down to one helical turn. It appears that DNA behaves as a Gaussian chain and is well described by the wormlike chain model at length scales beyond 3 helical turns (10.5 nm). Below this thr...

References 1. Soltani Bozchalooi, I., Youcef-Toumi, K., Burns, D. J. & Fantner, G. E. Compensator design for improved counterbalancing in high speed atomic force microscopy. The Review of scientific instruments 82(11), 113712 (2011). 2. Soltani Bozchalooi, I. & Youcef-Toumi, K. Multi-actuation and PI control: a simple recipe for high-speed and large-range atomic force microscopy. Ultramicroscop...

Biological processes rely on molecular interactions that can be directly measured using force spectroscopy techniques. Here we review how atomic force microscopy can be applied to force probe surfaces of living cells to single-molecule resolution. Such probing of individual interactions can be used to map cell surface receptors, and to assay the receptors' functional states, binding kinetics an...

Dielectrophoretic force microscopy is shown to allow for facile noncontact imaging of systems in aqueous media. Electrokinetic tip-sample forces were predicted from topography measurements of an interface and compared with experimental images. Correlation function and power spectral density analyses indicated that image feedback was maintained without mechanical contact using moderate potential...

Structured illumination microscopy (SIM) breaks the optical diffraction limit by illuminating a sample with a series of line-patterned light. Recently, in order to alleviate the requirement of precise knowledge of illumination patterns, structured illumination microscopy techniques using speckle patterns have been proposed. However, these methods require stringent assumptions of the speckle sta...

The monitoring of the deflection of a micro-cantilever, as the end of a sharp probe mounted at its end, i.e. the tip, interacts with a surface, forms the foundation of atomic force microscopy AFM. In a nutshell, developments in the field are driven by the requirement of obtaining ever increasing throughput and sensitivity, and enhancing the versatility of the instrument to simultaneously map th...

Conventional dynamic atomic force microscopy (AFM) can be extended to bimodal and multimodal AFM in which the cantilever is simultaneously excited at two or more resonance frequencies. Such excitation schemes result in one additional amplitude and phase images for each driven resonance, and potentially convey more information about the surface under investigation. Here we present a theoretical ...

We present an overview of the bimodal amplitude-frequency-modulation (AM-FM) imaging mode of atomic force microscopy (AFM), whereby the fundamental eigenmode is driven by using the amplitude-modulation technique (AM-AFM) while a higher eigenmode is driven by using either the constant-excitation or the constant-amplitude variant of the frequency-modulation (FM-AFM) technique. We also offer a com...