Molecular self-assembly presents a `bottom-up' approach to the fabrication of objects specified with nanometre precision. DNA
 molecular structures and intermolecular interactions are particularly
 amenable to the design and synthesis of complex molecular objects. We
 report the design and observation of two-dimensional crystalline forms
 of DNA that self-assemble from synthetic DNA double-crossover
 molecules. Intermolecular interactions between the structural units are
 programmed by the design of `sticky ends' that associate according to
 Watson-Crick complementarity, enabling us to create specific periodic
 patterns on the nanometre scale. The patterned crystals have been
 visualized by atomic force microscopy.

https://issg.cs.duke.edu/courses/spring04/cps296.4/papers/WLWS98.pdf

Design and self-assembly of two-dimensional DNA crystals

Since its invention a few years ago, the atomic force microscope has become one of the most widely used near-field microscopes. Surfaces of hard sample are imaged routinely with atomic resolution. Soft samples, however, remain challenging. An overview is presented on the application of atomic force microscopy to organic samples ranging from thin ordered films at molecular resolution to living cells. Fundamental mechanisms of the image formation are discussed, and novel imaging modes are introduced that exploit different aspects of the tip-sample interaction for local measurements of the micromechanical properties of the sample. As examples, images of Langmuir-Blodgett films, which map the local viscoelasticity as well as the friction coefficient, are presented.

From molecules to cells: imaging soft samples with the atomic force microscope

Atomic force microscopy (AFM) is a powerful, multifunctional imaging platform that allows biological samples, from single molecules to living cells, to be visualized and manipulated. Soon after the instrument was invented, it was recognized that in order to maximize the opportunities of AFM imaging in biology, various technological developments would be required to address certain limitations of the method. This has led to the creation of a range of new imaging modes, which continue to push the capabilities of the technique today. Here, we review the basic principles, advantages and limitations of the most common AFM bioimaging modes, including the popular contact and dynamic modes, as well as recently developed modes such as multiparametric, molecular recognition, multifrequency and high-speed imaging. For each of these modes, we discuss recent experiments that highlight their unique capabilities.

/pdf/imaging-modes-of-atomic-force-microscopy-for-application-in-3wyx0p8xt4.pdf

Imaging modes of atomic force microscopy for application in molecular and cell biology

Summary form only given. Nucleic acids have proven to be remarkably versatile as an engineering material for chemical tasks including the storage of information, catalyzing reactions creating and breaking bonds, mechanical manipulation using molecular motors, and constructing supramolecular structures. This talk will focus particularly on molecular self-assembly, giving examples of engineered DNA "tiles" that crystallize into two-dimensional sheets, one-dimensional tubes and ribbons, and information-guided patterns such as a Sierpinski triangle and a binary counter. A theme is how cooperative binding can be used to control nucleation and direct selective tile attachment. Such "algorithmic" self-assembly may provide a bottom-up fabrication method for creating complex, well-defined supramolecular structures that can be used as scaffolds or templates for applications such as arranging molecular electronic components into active circuits

/pdf/algorithmic-self-assembly-of-dna-2wgck1v5s8.pdf

Algorithmic Self-Assembly of DNA

Biomolecular Imaging with the Atomic Force Microscope

Reproducible images of uncoated DNA in the atomic force microscope (AFM) have been obtained by imaging plasmid DNA on mica in n-propanol. Specially sharpened AFM tips give images with reproducible features several nanometers in size along the DNA. Plasmids can be dissected in propanol by increasing the force applied by the AFM tip at selected locations.

/pdf/reproducible-imaging-and-dissection-of-plasmid-dna-under-decb8csgsm.pdf

Reproducible Imaging and Dissection of Plasmid DNA Under Liquid with the Atomic Force Microscope

https://web.physics.ucsb.edu/~hhansma/HHansma%20Science92%201180.pdf

C. Siegerist

Papers

Reproducible Imaging and Dissection of Plasmid DNA Under Liquid with the Atomic Force Microscope

Reproducible Imaging andDissection of Plasmid DNAUnderLiquid withthe Atomic Force Microscope