Design and characterisation of a dissolving microneedle patch for intradermal vaccination with heat-inactivated bacteria: A proof of concept study

Publication date: Available online 23 July 2018Source: International Journal of PharmaceuticsAuthor(s): Aoife M. Rodgers, Maelíosa T.C. McCrudden, Eva.M. Vincente-Perez, Alice V. Dubois, Rebecca J. Ingram, Eneko Larrañeta, Adrien Kissenpfennig, Ryan F. DonnellyAbstractThis work describes the formulation and evaluation of dissolving microneedle patches (MNs) for intradermal delivery of heat-inactivated bacteria. Pseudomonas aeruginosa, strain PA01, was used as a model bacterium. Utilising a simple, cost effective fabrication process, P. aeruginosa was heat-inactivated and formulated into dissolving MNs, fabricated from aqueous blends of 20% w/w poly(methylvinylether/maleic acid). The resultant MNs were of sufficient mechanical strength to consistently penetrate a validated skin model Parafilm M®, inserting to a depth of between 254 - 381 µm. MNs were successfully inserted into murine skin and partially dissolved. Analysis of MN dissolution kinetics in murine ears via optical coherence tomography showed almost complete MN dissolution 5 min post-insertion. Mice were vaccinated using these optimised MNs by application of one MN to the dorsal surface of each ear (5 min). Mice were subsequently challenged intranasally (24 h) with a live culture of P. aeruginosa (2x106 colony forming units). Bacterial load in the lungs of mice vaccinated with P. aeruginosa MNs was significantly (p= 0.0059) lower than those of their unvaccinated counterparts. This proof of concept work demonstrat...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research