ABSTRACT
The electrodes were deposited by photolithography onto glass microscope slides, with a chromium adhesion layer of 5 nm and a gold layer of 70 nm. The inter-electrode analysis chamber was 2 mm in diameter. The electric fields were generated by a four phase sinusoidal signal generator, and applied to the electrodes in the frequency range I 00 Hz to 1 0 MHz. Oocysts of C. cayetanensis were supplied by the Scottish Parasite Diagnostic Laboratory (SPDL), in either 2% potassium dichromate solution, or water. Oocysts were washed in ultra pure water and re-suspended in dilute solutions of normal phosphate buffered saline (Sigma Chemical Co.), which typically had conductivites of 0.6-1.0 mS/m, to reduce electrolysis and heat production at the electrodes. Sample results were visualised through a Nikon Optiphot 2 microscope using phase contrast microscopy with a magnification of x40 and a zoom of x2.25. Results were recorded to video tape for subsequent analysis using a NC colour video camera head (model TK-1280E) attached to the microscope.
