Scientists from the Netherlands and Iran proposed a method of controlled set and the allocation of ultrasmall liquid volumes (less than one picoliter) through the probe tip of the atomic force microscope to simultaneously study surface topology. The results of a study published in the journal Nanoscale.
Due to the presence of channels of small dimensions (of the order of microns), microfluidic devices allow to study the behavior of solutions of small volume with spatial resolution. Mixing small amounts of reagent at a certain point in space may allow to control the passage of chemical reactions. Mixing quantities smaller than one picoliter (10-12 liters) will provide an opportunity to explore reactions that take place in a single cell.
If manipulation ultramarine volumes of liquid to be carried out using the cantilever of an atomic force microscope, simultaneous visualization of surface topography and force spectroscopy. Previously, researchers have created a platform for controlled release of liquids through the probe, but each of the tanks was connected to a separate tip, so simultaneous spin liquids in one point was not possible.
Eleanor Julian Verlinden (Eleonoor Juliane Verlinden) with colleagues from Delft University of technology proposed to modify the cantilever of an atomic force microscope two microfluidic channels with holes at the tip of one lug. Each channel was connected to your tank, but dosing liquid was carried out through the holes on the end of one needle of the cantilever. Adjusting the pressure in the tank from -500 to 500 mbar relative to atmospheric, the authors were able to regulate the flow or fence Femto – and picolitre servings of liquids and the composition of the mixture exiting or sucked through the probe tip. To visualize the flow, the authors filled the tanks with fluorescein and rhodamine, capable of luminescence. The delicate balance between analyte diffusion and convection of fluid flow in channels and liquid, which placed the probe allowed precise volume of liquid and concentration of the analyzed substances.