A Minimal Optical Trapping and Imaging Microscopy System

作者：Hernandez Candia Carmen Noemi; Tafoya Martinez Sara; Gutierrez Medina Braulio^*

来源：PLos One, 2013, 8(2): e57383.

DOI：10.1371/journal.pone.0057383

We report the construction and testing of a simple and versatile optical trapping apparatus, suitable for visualizing individual microtubules (similar to 25 nm in diameter) and performing single-molecule studies, using a minimal set of components. This design is based on a conventional, inverted microscope, operating under plain bright field illumination. A single laser beam enables standard optical trapping and the measurement of molecular displacements and forces, whereas digital image processing affords real-time sample visualization with reduced noise and enhanced contrast. We have tested our trapping and imaging instrument by measuring the persistence length of individual double-stranded DNA molecules, and by following the stepping of single kinesin motor proteins along clearly imaged microtubules. The approach presented here provides a straightforward alternative for studies of biomaterials and individual biomolecules.

• 出版日期2013-2-25