Image Number 2 for United States Patent #5273525.
An apparatus for implanting macromolecules such as genes, DNA or pharmaceuticals into a preselected tissue region such as a muscle or an organ of a patient. A modified syringe is provided for injecting a predetermined quantity of a fluid medium carrying the preselected macromolecules. A signal generator is connected to the syringe for generating a predetermined electric signal. The syringe includes a pair of electrodes which are connected to the signal generator for applying an electric field in the tissue region. The field has a predetermined strength and duration in order to make the walls of a plurality of cells in the tissue region transiently permeable to permit the macromolecules to enter said preselected cells without damaging said cells. This enhances the uptake of macromolecules and thus enhances the therapeutic effect achieved. Alternate embodiments having twin needles and a blade may be utilized.