A flexographic preprint ink composition, which includes at least 3 weight percent of a pigment; at least 15 weight percent of a hydrolyzed gelatin; and water. Furthermore, the invention relates to a construct for generating such a cell, and to a method for separating such a cell from a population of cells. The first cylindrical section is fluidly connected to an intermediate passageway having a diameter larger than the first cylindrical section. The method also includes reading an index code from an index servo sector on the second surface and determining an index servo sector number from the index code. The isolation between ports provided by the balanced 90 hybrid coupler is approximately 35-40 db which is sufficient to allow the independent operation of transceivers connected to the input ports.