Enhancement of the SNR (signal to noise ratio) in single-molecule imaging is significantly important for improving image resolu-tion and distinguishing the fine structures of single molecules at a higher precision lev...Enhancement of the SNR (signal to noise ratio) in single-molecule imaging is significantly important for improving image resolu-tion and distinguishing the fine structures of single molecules at a higher precision level.Image processing techniques have dem-onstrated the remarkable capability to improve the SNR and the resolution level by breaking through some inherent limitations unresolved by instrument hardware optimization.In this paper, we focus on single-biomolecule imaging using atomic force mi-croscopy (AFM), a unique method in separated single-biomolecule imaging, and there was few suitable image processing tech-niques reported to increase the SNR of a single molecule’s AFM image.With the typical samples of separately dispersed DNA molecules, we replaced the classified averaging method, which is usually used when the molecules’ structure can be easily and repeatedly prepared, with the time averaging method to improve the SNR in a single molecule’s AFM imaging.Combining the time averaging technique with the image alignment method for the series of time-lapse AFM images of a single DNA molecule, we were able to improve the image’s SNR and recover some buried signals from the background noises.Furthermore, the fine structures of single molecules can potentially be further resolved if other image processing techniques are applied collaboratively with some newly developed imaging methods like Vibrating Mode Scanning Polarization Force Microscopy (VSPFM), and such combination will also be advantageous for the manipulation of single-biomolecules by AFM.In addition, the proposed algorithms for the estimations of drift, distortion and SNR are applicable for quantitative status characterization of AFM imaging.展开更多
基金supported by the National Basic Research Program of China (2006CB932505 and 2007CB936004)
文摘Enhancement of the SNR (signal to noise ratio) in single-molecule imaging is significantly important for improving image resolu-tion and distinguishing the fine structures of single molecules at a higher precision level.Image processing techniques have dem-onstrated the remarkable capability to improve the SNR and the resolution level by breaking through some inherent limitations unresolved by instrument hardware optimization.In this paper, we focus on single-biomolecule imaging using atomic force mi-croscopy (AFM), a unique method in separated single-biomolecule imaging, and there was few suitable image processing tech-niques reported to increase the SNR of a single molecule’s AFM image.With the typical samples of separately dispersed DNA molecules, we replaced the classified averaging method, which is usually used when the molecules’ structure can be easily and repeatedly prepared, with the time averaging method to improve the SNR in a single molecule’s AFM imaging.Combining the time averaging technique with the image alignment method for the series of time-lapse AFM images of a single DNA molecule, we were able to improve the image’s SNR and recover some buried signals from the background noises.Furthermore, the fine structures of single molecules can potentially be further resolved if other image processing techniques are applied collaboratively with some newly developed imaging methods like Vibrating Mode Scanning Polarization Force Microscopy (VSPFM), and such combination will also be advantageous for the manipulation of single-biomolecules by AFM.In addition, the proposed algorithms for the estimations of drift, distortion and SNR are applicable for quantitative status characterization of AFM imaging.
