Controlling DNA capture and propagation through artificial nanopores
Electrophorescing blopolymers across nanopores modulates the ionic current through the pore, revealing the polymer's diameter, length, and conformation. The rapidity of polymer translocation (similar to 30 000 bp/ms) in this geometry greatly limits the information that can be obtained for each base. Here we show that the translocation speed of lambda-DNA through artificial nanopores can be reduced using. optical tweezers. DNAs coupled to optically trapped beads were presented to nanopores. DNAs initially placed up to several micrometers from the pore could be captured. Subsequently, the optical tweezers reduced translocation speeds to 150 bp/ms, about 200-fold slower than free DNA. Moreover, the optical tweezers allowed us to "floss" single polymers back and forth through the pore. The combination of controlled sample presentation, greatly slowed translocation speeds, and repeated electrophoresis of single DNAs removes several barriers to using artificial nanopores for sequencing, haplotyping, and characterization of protein-DNA interactions.
Liphardt, J Univ Calif Berkeley, Biophys Grad Grp, Berkeley, CA 94720 USA Univ Calif Berkeley, Biophys Grad Grp, Berkeley, CA 94720 USA Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA Univ Calif Berkeley, Coll Chem, Berkeley, CA 94720 USA, 211CM, Times Cited:4, Cited References Count:23
Record created on 2008-11-17, modified on 2016-08-08