Pressure-driven microinjection (PMI) of porous-coated balloon for ultrafast endoluminal drug delivery across biological barriers.

Biological barriers play a crucial role in safeguarding the human body against pathogens yet pose severe challenges to efficient delivery of therapeutic drugs. Here, we introduce a pressure-driven microinjection (PMI) strategy for the robust and versatile delivery of functional species against biological barriers. With the benefits of elastic porous coating, this strategy enables the capillary suction of drug solutions, localized delivery, and ultrafast penetration through biological barriers by gentle pressure treatment. The penetration capacity is demonstrated by an unprecedented depth (~150 micrometers) of bovine serum albumin (66.4 kilodaltons) across aortic vessels under pressing for only 60 seconds. This spongy coating-based PMI technique can be integrated with medical balloon devices, offering endoluminal treatment within blood vessels, tracheas, and intestines. The in vivo evaluation indicated efficient trans-vascular delivery of 4-octyl itaconate, markedly reducing neointima hyperplasia. This PMI strategy provides a crucial insight for penetrative drug delivery across complex biological barriers.