An iontophoretic patch for transdermal delivery of biologically active agents includes at least two electrodes in contact with at least two hydrogel reservoirs. At least one of the hydrogel reservoirs carries at least one active agent and, in use of the iontophoretic patch, is disposed on a user's skin and delivers at least one active agent into the skin. The patch includes a control unit to generate a stimulation pattern having stimulation parameters delivered to stimuli locations on the skin. A stimulation unit generates a time sequence of pulses from the stimulation parameters generated by the control unit. The patch further includes a demultiplexing unit configured to perform independent spatio-temporal distribution of the electrical pulses in the time sequence of pulses to at least one electrode; at least one optical sensing system, for continuously measuring an amount of the active agent in the hydrogel reservoir; and a feedback unit.

Disclosed herein are methods and compositions for generating pacemaker cells from non-pacemaker cardiomyocytes. For example, the method includes the step of culturing the non-pacemaker cardiomyocytes with silk fibroin so that the silk fibroin induces the transformation of at least a portion thereof into pacemaker cells.

Apparatus is provided for treating hyaline cartilage of a subject, the apparatus including a chondral implant, which includes a first exposed electrode surface and which is configured to be implanted in osteochondral tissue of the subject. A second exposed electrode surface is configured to be implanted in a body of the subject. Control circuitry is configured to promote regeneration of the hyaline cartilage by driving the first and the second exposed electrode surfaces to drive nutrients toward the first exposed electrode surface. Other embodiments are also described.

A method is provided for treating an intervertebral disc of a subject, the method including implanting at least one intra-pulposus exposed electrode surface in a nucleus pulposus of the intervertebral disc, and implanting one or more extra-pulposus exposed electrode surfaces outside the nucleus pulposus, in electrical communication with the intervertebral disc. Control circuitry, while electrically coupled to the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces, is activated to drive fluid and introduce nutritional substances into the intervertebral disc, by applying a voltage between the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces. Other embodiments are also described.

Compositions and methods are provided for genetically modifying cells to guide in situ chemical synthesis of electroactive, conductive, or insulating polymers on plasma membranes, organelle membranes, or subcellular surfaces of cells. In particular, compositions and methods are provided for genetically modifying excitable cells such as neurons, muscle cells, and endocrine cells to guide in situ chemical synthesis of polymers on the extracellular side of the plasma membrane. The subject methods can be used in various applications, for example, to assemble polymers in vivo at targeted locations to modulate electrical conduction and create new electrical conduction pathways, allow cell-type-specific neuromodulation, provide a conductive structure on cells for connection to electrodes, sensors, or other external electronic and electrochemical devices, and create a durable structure to replace damaged tissue for use in regenerative medicine.

An apparatus includes multiple first reservoirs and multiple second reservoirs joined with a substrate. Selected ones of the multiple first reservoirs include a reducing agent, and first reservoir surfaces of selected ones of the multiple first reservoirs are proximate to a first substrate surface. Selected ones of the multiple second reservoirs include an oxidizing agent, and second reservoir surfaces of selected ones of the multiple second reservoirs are proximate to the first substrate surface.

A system and method for powering a medical device that includes a fixture configured for periodic patient proximity; external electrical coupling device integrated into the fixture wherein the external electrical coupling device comprises at least one external energy coupler and is configured to detect presence of an electrical medical device implant in a transmission zone of the external electrical coupling device; an electrical medical device implant, wherein the electrical medical device implant comprises at least one implant energy coupler; and wherein the external electrical coupling device is configured to couple to the implantable medical device through a wireless energy transmission between the external energy coupler and the implant energy coupler when presence of the implantable medical device is within a transmission zone.

A method is provided for treating an intervertebral disc of a subject, the method including implanting at least one intra-pulposus exposed electrode surface in a nucleus pulposus of the intervertebral disc, and implanting one or more extra-pulposus exposed electrode surfaces outside the nucleus pulposus, in electrical communication with the intervertebral disc. Control circuitry, while electrically coupled to the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces, is activated to drive fluid and introduce nutritional substances into the intervertebral disc, by applying a voltage between the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces. Other embodiments are also described.

An orthopedic prosthesis for stimulating bone growth may include a substrate having at least one bone-facing surface and at least one internal surface, at least one piezoelectric nanostructure coupled to the at least one bone-facing surface of the substrate, at least one charge storing material placed within the orthopedic prosthesis proximate the at least one internal surface, and an interconnect in electrical communication with the at least one piezoelectric nanostructure and the charge storing material. The at least one piezoelectric nanostructure may be configured to generate an electric charge in response to at least one mechanical force applied to the at least one piezoelectric nanostructure and the interconnect may be configured to transfer the electric charge to the at least one charge storing material to promote bone in-growth within the orthopedic prosthesis and/or on the at least one bone-facing surface.

Apparatus is provided for treating an intervertebral disc of a subject, the apparatus including: at least one intra-pulposus exposed electrode surface, which is configured to be implanted in a nucleus pulposus of the intervertebral disc; and one or more extra-pulposus exposed electrode surfaces, which are configured to be implanted outside the nucleus pulposus, in electrical communication with the intervertebral disc. Control circuitry is electrically coupled to the at least one intra-pulposus exposed electrode surface and one or more extra-pulposus exposed electrode surfaces. The control circuitry is configured to drive fluid and introduce nutritional substances into the intervertebral disc, by applying a voltage between the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces. Other embodiments are also described.