Techniques for etching through a low capacitance dielectric layer in a plasma processing chamber are disclosed. In a preferred embodiment, a multiple biotinylated antibody capable of binding analyte is bound to an anti-biotin antibody labelled with colloidal gold and wicked up the dipstick with test solution thought to contain analyte. A contact tip is disposed within the nozzle assembly and includes at least one aperture extending from an exterior portion to an internal cavity, an exit orifice, a distal end face, and an exterior surface extending between the at least one aperture and the distal end portion of the contact tip. In the closed position, however, cigarette ash and butts cannot enter or exit the storage system of the litter disposal device.