An aspect of embodiment relates to a digital bio disc including new valve control means and fluid movement system, a digital bio disc driver apparatus, and an assay method using the same. 5 microns and about 1500 microns, the inorganic binder is less than about 75 percent, by weight, of the abrasive agglomerate, and the bulk density of the abrasive agglomerate is less than about 90 percent of the bulk density of the abrasive grains. In a specific embodiment, the invention relates to the use of transitional metals such as Cu and ferrous ions to increase the efficacy of peroxides such as benzoyl peroxide. A test of the sensor includes a pulse in the power voltage so as to generate a corresponding but delayed pulse in the light from the light source. If the optical disc is clamped by a chucking unit of a drive, it is clamped by making the clamp reference plane on the major surface of the light transmitting layer contact with a mounting surface of a table for mounting the disc, and making a magnetic metal plate contact with the major surface of the disc substrate, and then sandwiching the optical disc between.