A delivery system, including a polymeric material for storing molecules and/or particles wherein the molecules and/or particles are substantially bound to said polymeric material through: the polymeric material comprising an electrical charge and the molecules and/or particles comprising an electrical charge opposite to the electrical charge of the polymeric material; and/or the molecules and/or particles being physically trapped within pores of the polymeric material; and an ultrasonic transducer configured to apply an ultrasonic signal to the polymeric material to release the molecules and/or particles and to transport the released molecules and/or particles through the polymeric material to a surface for delivery to an entity.