&lt;title&gt;Atomic force microscopy using small cantilevers&lt;/title&gt;

Walters, D. A.; Viani, Mario; Paloczi, George T.; Schaeffer, Tilman E.; Cleveland, J. P.; Wendman, Mark A.; Gurley, G.; Elings, Virgil B.; Hansma, Paul K.

doi:10.1117/12.271227

Cited by 22 publications

(12 citation statements)

References 3 publications

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“…Frame rates of 0.6-1.5 frames/s have been achieved, with tip speeds approaching 60 mm/s [51][52][53][54]. Ando et al [55] used small cantilevers and a specialized AFM to watch myosin V molecules in motion on a mica surface with a frame rate of 12.5 frames/s and tip speed of 0.6 mm/s.…”

Section: High-speed Tapping Mode Afm In Liquidmentioning

confidence: 98%

Improving tapping mode atomic force microscopy with piezoelectric cantilevers

et al. 2004

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Section: High-speed Tapping Mode Afm In Liquidmentioning

confidence: 98%

Improving tapping mode atomic force microscopy with piezoelectric cantilevers

et al. 2004

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“…The development of high-speed AFM (HS-AFM) using cantilevers with μs-response time allowed an increase in imaging rates by about 1000-fold, providing a new tool to visualize protein and cellular dynamics at video rates (Ando et al 2001; Humphris et al 2005; Viani et al 1999). The developments by the groups of Hansma and Ando were based on the miniaturization of the main AFM components, such as piezoelectric elements and, especially, adapted optics allowing the use of ultrashort cantilevers (Ando et al 2001, 2008; Walters et al 1997, 1996; Schaeffer et al 1997). HS-AFM allowed, for example, to the landmark observation of myosin V walking on an actin filament in real time (Kodera et al 2010).…”

Section: Introductionmentioning

confidence: 99%

High-speed force spectroscopy: microsecond force measurements using ultrashort cantilevers

2019

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Complete understanding of the role of mechanical forces in biological processes requires knowledge of the mechanical properties of individual proteins and living cells. Moreover, the dynamic response of biological systems at the nano-and microscales span over several orders of magnitude in time, from sub-microseconds to several minutes. Thus, access to force measurements over a wide range of length and time scales is required. High-speed atomic force microscopy (HS-AFM) using ultrashort cantilevers has emerged as a tool to study the dynamics of biomolecules and cells at video rates. The adaptation of HS-AFM to perform highspeed force spectroscopy (HS-FS) allows probing protein unfolding and receptor/ligand unbinding up to the velocity of molecular dynamics (MD) simulations with sub-microsecond time resolution. Moreover, application of HS-FS on living cells allows probing the viscoelastic response at short time scales providing deep understanding of cytoskeleton dynamics. In this minireview, we assess the principles and recent developments and applications of HS-FS using ultrashort cantilevers to probe molecular and cellular mechanics.

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“…A high resonance frequency in liquid is required to generate a high tapping frequency; also required is a low spring constant, so as to minimize the tip-sample interaction force. These conflicting requirements can be met only with small cantilevers (8,9). Every circuit in the feedback loop must have a wide bandwidth.…”

mentioning

confidence: 99%

A high-speed atomic force microscope for studying biological macromolecules

Ando

Kodera

Takai

et al. 2001

Proc. Natl. Acad. Sci. U.S.A.

994

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The atomic force microscope (AFM) is a powerful tool for imaging individual biological molecules attached to a substrate and placed in aqueous solution. At present, however, it is limited by the speed at which it can successively record highly resolved images. We sought to increase markedly the scan speed of the AFM, so that in the future it can be used to study the dynamic behavior of biomolecules. For this purpose, we have developed a high-speed scanner, free of resonant vibrations up to 60 kHz, small cantilevers with high resonance frequencies (450 -650 kHz) and small spring constants (150 -280 pN͞nm), an objective-lens type of deflection detection device, and several electronic devices of wide bandwidth. Integration of these various devices has produced an AFM that can capture a 100 ؋ 100 pixel 2 image within 80 ms and therefore can generate a movie consisting of many successive images (80-ms intervals) of a sample in aqueous solution. This is demonstrated by imaging myosin V molecules moving on mica (see http:͞͞www.s.kanazawa-u.ac.jp͞phys͞biophys͞bmvmovie.htm). One of the advantages of the atomic force microscope (AFM) (1) is its capacity to image individual biomolecules in, say, a buffered solution containing ions at physiological concentrations (2, 3). Such capacity suggests that the instrument can be used to record the dynamic behavior of such molecules. In practice, however, only very slow processes can be recorded (2, 4-6), because commercially available AFMs require minutes to form an acceptable image, and many interesting biological processes occur at much higher rates. To understand, and overcome, the factors that limit the scanning rate of an AFM, we begin by considering relations between the characteristics of the constituting components.We consider only the ''tapping mode'' of AFM operation (Digital Instruments, Santa Barbara, CA). This is the mode suitable for imaging biological macromolecules, because vertical oscillation of the cantilever at (or near to) its resonance frequency reduces lateral forces between the tip and the sample (7). The oscillating tip briefly taps the surface at the bottom of each swing, resulting in a decrease in oscillation amplitude. During the x-y scan of the sample stage a feedback loop (see below) keeps this decrease (and hence the tapping force) constant; this is necessary for minimizing the deformation of soft samples. The error signal-the difference between a preset signal and the rms amplitude of the cantilever-is fed into a proportional-integraldifferential (PID) feedback circuit. The PID output is amplified and then sent to the z-piezo actuator; this is repeated until the error signal returns to zero. For the three-dimentional movement of the sample stage to follow the sample topography accurately, the bandwidth of the feedback loop should be comparable to, or larger than, the frequency determined by the x-y scan velocity and the apparent width of the features on the surface. To increase the imaging bandwidth, all elements in the feedback loop have to be optimi...

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<title>Atomic force microscopy using small cantilevers</title>

Cited by 22 publications

References 3 publications

Improving tapping mode atomic force microscopy with piezoelectric cantilevers

Improving tapping mode atomic force microscopy with piezoelectric cantilevers

High-speed force spectroscopy: microsecond force measurements using ultrashort cantilevers

A high-speed atomic force microscope for studying biological macromolecules

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