First, adhesive from the HybriWell is peeled off and the HybriWell is attached over the area of the slide printed with the gelatin-DNA solution. Second, 200ul of transfection mix is pipetted into one of the HybriWell ports; the mixture will distribute evenly over the array. The array is then incubated, with temperature and time dependent on the cell types used. Third, the transfection mix is pipetted away and the HybriWell removed with a thin-tipped forceps. Fourth, the printed slide treated with transfection reagent is placed into a square dish with the printed side facing up. Fifth, the harvested cells are gently poured onto the slides (not on the printed areas). Finally, the dish is placed in a 37°C, 5% CO humidified incubator and incubated overnight.