Enhancing the injectability of high concentration drugs via core annular flows

Abstract

High concentration drug formulations that can be delivered via subcutaneous injections offer tremendous benefits to global health, but their high viscosity prevents injectability through medical needles. Current approaches to solve this problem face several challenges ranging from cross contamination and high cost to needle clogging and protein inactivation. Here we report a simple method to enhance formulation injectability through a core annular flow that lubricates viscous transport through a needle. We study the importance of different flow regimes and density based eccentricity in dictating lubrication in the needle. Finally, we quantify the maximum pressure reduction that can be achieved with such a lubricating core annular flow.