کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1677681 | 1518356 | 2012 | 6 صفحه PDF | دانلود رایگان |
The authors describe a method for biomolecular force clamp measurements using atomic force microscope (AFM) cantilevers and micromachined membrane-based electrostatic actuators. The actuators comprise of Parylene membranes with embedded side actuation electrodes and are fabricated on a silicon substrate. The devices have a displacement range of 1.8 μm with 200 V actuation voltage, and displacement uncertainty is 0.8 nm, including the noise and drift. The settling time, limited by the particular amplifier is 5 ms, with an inherent range down to 20 μs. A force clamp measurement setup using these actuators in a feedback loop has been used to measure bond life-times between human IgG and anti-human IgG molecules to demonstrate the feasibility of this method for biological experiments. The experimental findings are compared with a molecular pulling experiment and the results are found to be in good agreement.
► We fabricate and characterize micromachined electrostatic actuators for AFM.
► We integrate the actuators to an AFM system and build a force-clamp setup.
► We develop a software-based controller for the force-clamp setup.
► We perform biomolecular experiments to assess molecular bond life-times.
► We compared the biological results with the conventional AFM methods.
Journal: Ultramicroscopy - Volume 122, November 2012, Pages 26–31