1 this invention allows for precise highly reproducible deposition of foreign materials into the cell or the yolk the following description assumes that one desires to deposit foreign materials into the cytoplasm center for every embryo when the micropipette tip has a significant tilting angle e g gt 5 u00b0 as shown in fig5 e h micropipette motion control sequence can be made slightly different from the above mentioned in order to minimize cellular damage the two different steps are i principal plane 54 still crosses cytoplasm center o but is parallel to micropipette tip 8 from the side view and ii during penetration and retraction the micropipette moves along the direction of its principle axes fig5 g h instead of purely along the x e direction although the following description corresponds to the case shown in fig5 a d the invention can also be implemented as shown in fig5 e h denote the pitch i e spacing between two adjacent holes 201 along the x t and y t directions as u03b4x and u03b4y denote the number of embryos along the x t and y t directions as m and n starting with the first embryo fig6 a d positioner 1 is controlled to travel along.