Control of the substrate wetting properties on slippery surfaces can prevent the pinning of the drop contact line, which will, therefore, suppress the coffee ring effect by reducing the number of particles deposited at the contact line. Drops on superhydrophobic or liquid impregnated surfaces are less likely to have a pinned contact line and will suppress ring formation. Drops with an oil ring formed at the drop contact line have high mobility and can avoid the ring formation on hydrophobic surfaces.