Ruddy Bryan P, Mckeage James W, Williams Rhys M J, Nielsen Poul M F, Taberner Andrew J
Annu Int Conf IEEE Eng Med Biol Soc. 2015;2015:7341-4. doi: 10.1109/EMBC.2015.7320087.
We present a new design for a needle-free injector ampoule, using two concentric pistons to pressurize the fluid during the injection. The smaller, inner piston is used to provide an initial high-velocity piercing jet; it then engages the outer piston to deliver the remaining drug via a low-velocity jet. The goal of this design is to enable needle-free delivery of relatively large volumes to controlled depths in tissue, a task impractical with conventional ampoules and actuators. We demonstrate this concept by constructing a 1.2mL ampoule, measuring the jet velocity it produces in free air, and performing a set of injections into post-mortem porcine tissue. The ampoule smoothly produces the two desired phases of an injection, with a smooth transition of jet velocity as the two pistons engage. The injection is able to penetrate porcine skin to a controlled depth and deliver fluid to the subcutaneous and/or intramuscular layers, though further investigation is required to ensure that all of the fluid delivered can be retained at the desired depth.
我们展示了一种用于无针注射器安瓿的新设计，该设计在注射过程中使用两个同心活塞对流体进行加压。较小的内活塞用于产生初始高速穿刺射流；然后它与外活塞接合，通过低速射流输送剩余的药物。这种设计的目标是能够将相对大量的药物无针输送到组织中的可控深度，这对于传统安瓿和注射器来说是一项不切实际的任务。我们通过构建一个1.2毫升的安瓿、测量其在自由空气中产生的射流速度以及对死后猪组织进行一系列注射来验证这一概念。该安瓿能够顺利产生注射所需的两个阶段，随着两个活塞接合，射流速度平稳过渡。该注射能够穿透猪皮至可控深度，并将流体输送到皮下和/或肌肉层，不过还需要进一步研究以确保所输送的所有流体都能保留在所需深度。
