Molecular recognition imaging using tuning fork-based transverse dynamic force microscopy

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• 作者：Manuel Hofer ; Stefan Adamsmaier ; Thomas S. van Zanten ; Lilia A. Chtcheglova ; Carlo Manzo ; Memed Duman ; Barbara Mayer ; Andreas Ebner ; Manuel Moertelmaier ; Gerald Kada ; Maria F. Garcia-Parajo ; Peter Hin
• 关键词：ning fork ; Atomic force microscopy ; Shear-force microscopy ; Molecular recognition ; Avidin– ; biotin
• 刊名：Ultramicroscopy
• 出版年：2010
• 出版时间：May 2010
• 年：2010
• 卷：110
• 期：6
• 页码：605-611
• 全文大小：1525 K

文摘

We demonstrate simultaneous transverse dynamic force microscopy and molecular recognition imaging using tuning forks as piezoelectric sensors. Tapered aluminum-coated glass fibers were chemically functionalized with biotin and anti-lysozyme molecules and attached to one of the prongs of a 32 kHz tuning fork. The lateral oscillation amplitude of the tuning fork was used as feedback signal for topographical imaging of avidin aggregates and lysozyme molecules on mica substrate. The phase difference between the excitation and detection signals of the tuning fork provided molecular recognition between avidin/biotin or lysozyme/anti-lysozyme. Aggregates of avidin and lysozyme molecules appeared as features with heights of 1–4 nm in the topographic images, consistent with single molecule atomic force microscopy imaging. Recognition events between avidin/biotin or lysozyme/anti-lysozyme were detected in the phase image at high signal-to-noise ratio with phase shifts of 1–2°. Because tapered glass fibers and shear-force microscopy based on tuning forks are commonly used for near-field scanning optical microscopy (NSOM), these results open the door to the exciting possibility of combining optical, topographic and biochemical recognition at the nanometer scale in a single measurement and in liquid conditions.