An integrated circuit is formed to include a first polarity MOS transistor and a second, opposite, polarity MOS transistor. A poly-SiGe layer with a Ge density profile which decreases linearly from the bottom of the gate toward the top of the gate is formed and a poly-SiGe gate having a negative slope is formed by patterning the poly-SiGe layer. Aminoalcohol lipidoids may be prepared from racemic or stereochemically pure epoxides. The upper and lower conduits in combination with an optional aperture in the base member, may together form a continuous conduit.