Advanced Electrohydrodynamic Atomisation Engineered Microneedle Coatings

Transdermal drug delivery (TDD) is an emerging field in the pharmaceutical remit compared to conventional methods (oral and parenteral). Microneedle (MN) based devices have gained significant interest as a strategy to overcome the skins formidable barrier; the stratum corneum and enhance drug delivery. The research presented here shows the successful coating of MNs with polymeric dye composites using Electrohydrodynamic atomisation (EHDA). Initially the rheological behaviours of polymeric solutions and morphological characterisation was carried out. This was followed by Quality by Design (QBD) implementation for the optimisation of the key process parameters in EHDA. Here, the electrosprayed nanoparticles and electrospun nano/micro fibres consisted of a polymeric matrix and dye. Eight formulations were assessed consisting of 5% w/v of polycaprolactone (PCL) in dichloromethane (DCM) and 5% w/v polyvinylpyrrolidone (PVP) in ethanol. A full factorial Design of Experiments (DoE) was used to assess the various parameters (applied voltage, deposition distance and flow rate). Further particle and fibre analysis was carried out using Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR), particle/fibre size distribution. In addition to this, in vitro release studies were carried out using fluorescein (FL) and rhodamine B (RhB) as model dyes and in vitro permeation studies were applied. From optimising EHDA more than 52% of particles were under 500 nm and fibres were in the micron range. In vitro drug release studies showed 100% drug release after 7 days for PCL particles and fibres. It also showed 100% drug release within 120 min for PVP particles and 300 minutes for PVP fibres. The release kinetics and the permeation study showed that the MN successfully pierced the membrane and the Es and Esp MN coatings released a large amount of the loaded drug within 6 hours for all formulations. This study has demonstrated the capability of these robust MNs to encapsulate a diverse range of drugs within a polymeric matrix giving rise to the potential of developing personalised medical devices.

Name dc:type.qualificationname

PhD

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

De Montfort University

Year dc:date.issued

2020

Author dc:creator

• Ali, Radeyah

Licence

• https://dora.dmu.ac.uk/bitstreams/e2aa9a24-6d29-4067-80f5-be0d93fd5643/download