TuDelft and Ports will provide a brief report summarising how to produce a horizontal magnetic tweezer system.  This report will draw on previous reports and material gathered from other Workpackages.

Outcomes:

How to show proof of principle for such a device was discussed at the 3rd Mol Switch Workshop.  It was agreed to make best use of existing technology, in the form of the Magnetic Tweezer Set-ups, to achieve this aim.

After further discussion it was decided to build a system with combined vertical and horizontal stretching of the DNA. Indeed a system was built where the DNA was oriented with an angle of 45 degrees, allowing horizontal access to the DNA.

NPL have developed a Hall Effect Sensor containing an array of 1 μm size Hall probes fabricated from cobalt or bismuth on a transparent sapphire substrate, i.e. compatible with the magnetic tweezers set-up, was fabricated.

NPL have also determined the magnetic characteristics of both commercially available and home-build magnetic beads were studied. It was shown that the resolution of the scanning Hall microscope is sufficient to resolve the smallest available commercial beads (1 μm).