Stachowiak Jeanne C, Li Thomas H, Arora Anubhav, Mitragotri Samir, Fletcher Daniel A
University of California, Berkeley, Department of Mechanical Engineering, Berkeley, CA 94720, USA.
J Control Release. 2009 Apr 17;135(2):104-12. doi: 10.1016/j.jconrel.2009.01.003. Epub 2009 Jan 21.
Many modern pharmaceutical therapies such as vaccines and macromolecular drugs benefit from transdermal delivery. Conventional transdermal drug delivery via hypodermic needles causes pain, non-compliance, and potential contamination. Alternative transdermal strategies that deliver drugs in a quick, reliable, painless, and inexpensive way are needed. Jet injectors, which deliver drugs through the skin using a high-speed stream of liquid propelled by compressed springs or gasses, provide a needle-free method of trandermal drug delivery. However, poor reliability as well as painful bruising and bleeding characterize these devices, due in part to the high and constant jet velocity with which drugs are delivered. Toward improved reliability and reduced pain, we have developed a jet injector capable of dynamic control of jet velocity during a single injection pulse. Using this device, we demonstrate that temporal control of jet velocity leads to independent control of penetration depth, by adjusting time at high velocity, and delivered dose, by adjusting time at low velocity, in model materials. This dynamic control of jet velocity creates the potential for better control of needle-free injections, as demonstrated through injection studies on whole ex vivo human skin samples.
许多现代药物疗法，如疫苗和大分子药物，都受益于透皮给药。通过皮下注射进行的传统透皮给药会引起疼痛、患者依从性差以及潜在的污染。因此，需要能够以快速、可靠、无痛且经济的方式给药的替代透皮策略。喷射注射器利用压缩弹簧或气体推动的高速液体流将药物输送到皮肤中，提供了一种无针透皮给药方法。然而，这些设备存在可靠性差以及会造成疼痛的瘀伤和出血等问题，部分原因是药物输送时的喷射速度高且恒定。为了提高可靠性并减轻疼痛，我们开发了一种能够在单次注射脉冲期间动态控制喷射速度的喷射注射器。使用该设备，我们证明了在模型材料中，通过调整高速时间来独立控制穿透深度，以及通过调整低速时间来独立控制给药剂量，对喷射速度进行时间控制可以实现这一点。如通过对完整的离体人体皮肤样本进行注射研究所示，这种对喷射速度的动态控制为更好地控制无针注射创造了潜力。
