Development and Performance of a Controllable Autoloading Needle-Free Jet Injector

Abstract

A jet injector platform technology that provides improved performance over existing jet injectors through the use of a controllable linear Lorentz-force actuator and software-based control system has been developed. Injectors designed on this platform are capable of delivering injections using arbitrary pressure pulse shaping. Pulse shaping has been shown to allow a wide degree of control over the depth to which the injection is delivered. A software-based injector control system improves repeatability and allows for automatic reloading of the injector, a task that would be difficult to implement using existing jet injector platforms. A design for a prototype autoloading controllable jet injector (cJI) based on this platform is detailed. The injection capability of this cJI was evaluated both in-vitro and in-vivo using a tissue analog, excised porcine tissue, and ovine tissue. An analysis of the cJI’s performance indicates that this design is capable of delivering a controllable volume of fluid to a controllable depth based entirely on the parameter’s input into the control software.

Inkjet printing for pharmaceutics – A review of research and manufacturing

“…The move to inkjet printing promises to improve monodispersity and provide bettter control of dosage volume. An additional method for drug delivery is being explored, where special jetforming techniques are used to produce supersonic jets of the API to penetrate the dermis layer and create needle-free injection techniques (Stachowiak et al 2009, Hemond et al 2011. Very high jet velocities have been achieved but such techniques are still under development.…”

Depth-controlled laser-induced jet injection for direct three-dimensional liquid delivery

“…This was achieved using a laser-actuated needle-free microjet injector, in which a laser-induced shockwave propels a liquid through a nozzle. However, as this precise laseractuated microjetting method is nozzle-based, it requires a reloading step between each injection, which limits its throughput or demands specific engineering efforts for designing an automatic reloading feature [7].…”

“…To improve control over the injection depth and delivered dose, several groups have recently developed needle-free jet injectors able to dynamically actuate the jet velocity [4] or jet pressure [7] during the injection. This new generation of jet injectors first produces a brief powerful jet to reach the targeted layer and then a longer jet, below the skin penetration threshold, to deliver a defined dose.…”

“…This new generation of jet injectors first produces a brief powerful jet to reach the targeted layer and then a longer jet, below the skin penetration threshold, to deliver a defined dose. These devices are based on a complete redesign of standard jet injectors to operate over a wider range of velocities (60-160 m/s) [4] or pressure (5-50 MPa) [7], which was respectively achieved with a piezo-and Lorentz-force actuator.…”

“…Indeed, many existing springand gas-actuated jet injectors operate at a single velocity, usually between 100 and 200 m/s [2]. This does not allow adapting to the broad variety of mechanical properties of skin and soft tissue in the population, thus occasionally resulting in uncontrolled drug delivery into deeper layers and excitation of nerve endings [4,[6][7][8].…”