Highly concentrated biologic drug formulations that can be delivered via subcutaneous injections offer tremendous benefits to global health, but they cannot be injected via commercial syringes and needles due to their high viscosities. 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 injectability using a core annular flow, where the transport of highly viscous drugs through a needle is made easier, thanks to co-axial lubrication by a less viscous fluid. We establish a phase diagram to ensure optimally lubricated core annular flow while minimizing the volume fraction of lubricant. This technique allows us to experimentally obtain up to a 7x reduction in injection pressure for the largest viscosity ratio that was tested, which is in agreement with theoretical predictions for eccentric core annular flows. Finally, we implement these findings into the design and fabrication of a double barreled syringe that significantly expands the range of injectable concentrations of several biologic formulations.

Core annular flows to enhance the injectability of high concentration drug formulations

Macromolecular Chemistry: The Second Century

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ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.