Generation of 1024 different conditions. (a) A set of filters used to generate multiple conditions in an MMV chip. In each of these filters, if the N-bit is 1 (“go”) for the (i + 1)-th least significant bit in the binary number, then the corresponding position of filter Fi is a hole (allowing the liquid to pass through). On selective addition of 10 species of materials to an acceptor MMV using these filters, 1024 different conditions (corresponding to 1024 different binary numbers) were generated (for detail, see Additional file 11: Figure S10). (b) Lysozyme crystallization in MMV. The 1024 different conditions were generated for determining the optimum crystallization conditions. A combination of pH differences (2.9–9.6) and NaCl concentration differences (0–1.5 M) was examined (see Methods). In the inset, magnified images are shown for some MMV wells. The scale bar is 100 μm.