An ordinary golf ball is cleaned and then treated with an emulsion depositing in the dimples a hologram having the capacity to reflect a pre-selected wavelength of laser-beam. Also provided are polypeptides encoded by the nucleic acids associated with T1D. The drop volume feedback subsystem control volumes of the reagents dispensed by the drop-on-demand mechanism so that the drop-on-demand mechanism dispenses the reagents on the diagnostic test strips in the desired volumes.