A cylindrical cam device includes an axle and a plurality of disk portions disposed about the axle. The plurality of disk portions define a plurality of interstitial regions disposed between the plurality of disk portions. Each of the plurality of disk portions comprises a radial edge. The radial edge of each of the plurality of disk portions comprises a material or structure capable of retaining a liquid and releasing at least a portion of the liquid onto a substrate. A method for facilitating electrophoretic analysis of biological samples utilizing the cylindrical cam device is also disclosed.