Many vaccines and important drugs require multi-bolus regimens that can be financially and physically stressing for patients due to complicated schedules, pain, inconvenience, and the cost of the injections. Low-patient compliance, together with many syringe/needle-related problems, prevents the successful implementation of global immunization campaigns and enables the resurgence of deadly infectious diseases. Here, we present a high through-put and scalable 3D additive-manufacturing approach to create a biodegradable, fully-embedded microneedle (MN) system which only requires a one-time insertion into skin to automatically perform a delayed burst-release of therapeutic payloads after programmable times, an advantage which has not been achieved by any other reported MNs. We employ a micro-molding and 3D alignment process to create core-shell MNs and rely on degradation of the MN shells to engineer the burst time. By using different biodegradable shells of Poly(D,L-lactide-co-glycolide) (PLGA), we can tune the delayed burst-times from a few days to months, both for <i>in vitro</i> and <i>in vivo </i>conditions. We show that MNs loaded with different vaccine antigens can induce a significant immune response in rats, similar to that obtained from multiple subcutaneous bolus injections. These MNs therefore offer an excellent platform for injection-free, one-time administration of vaccines to replace problematic injections in conventional vaccination processes, with the potential to significantly enhance patient compliance

3D manufacturing of biodegradable polymers at small scales for single-administration vaccines and drugs

ACS Spring 2022

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