title: Microwave-Assisted Preparation of Hydrogel-Forming Microneedle Arrays for Transdermal Drug Delivery Applications.
abstract: 1A microwave (MW)-assisted crosslinking process to prepare hydrogel-forming microneedle (MN) arrays was evaluated. Conventionally, such MN arrays are prepared using processes that includes a thermal crosslinking step. Polymeric MN arrays were prepared using poly(methyl vinyl ether-alt-maleic acid) crosslinked by reaction with poly(ethylene glycol) over 24 h at 80 °C. Polymeric MN arrays were prepared to compare conventional process with the novel MW-assisted crosslinking method. Infrared spectroscopy was used to evaluate the crosslinking degree, evaluating the area of the carbonyl peaks (2000-1500 cm-1). It was shown that, by using the MW-assisted process, MN with a similar crosslinking degree to those prepared conventionally can be obtained in only 45 min. The effects of the crosslinking process on the properties of these materials were also evaluated. For this purpose swelling kinetics, mechanical characterisation, and insertion studies were performed. The results suggest that MN arrays prepared using the MW assisted process had equivalent properties to those prepared conventionally but can be produced 30 times faster. Finally, anin vitrocaffeine permeation across excised porcine skin was performed using conventional and MW-prepared MN arrays. The release profiles obtained can be considered equivalent, delivering in both cases 3000-3500 μg of caffeine after 24 h.
authors.affiliation: Chair in Pharmaceutical Technology School of Pharmacy Queens University Belfast, Medical Biology Centre 97 Lisburn Road Belfast BT9 7BL UK.
authors.forename: Eneko
authors.initials: E
authors.lastname: Larrañeta
authors.affiliation: Chair in Pharmaceutical Technology School of Pharmacy Queens University Belfast, Medical Biology Centre 97 Lisburn Road Belfast BT9 7BL UK.
authors.forename: Rebecca E M
authors.initials: RE
authors.lastname: Lutton
authors.affiliation: Chair in Pharmaceutical Technology School of Pharmacy Queens University Belfast, Medical Biology Centre 97 Lisburn Road Belfast BT9 7BL UK.
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Brady
authors.affiliation: Chair in Pharmaceutical Technology School of Pharmacy Queens University Belfast, Medical Biology Centre 97 Lisburn Road Belfast BT9 7BL UK.
authors.forename: Eva M
authors.initials: EM
authors.lastname: Vicente-Pérez
authors.affiliation: Chair in Pharmaceutical Technology School of Pharmacy Queens University Belfast, Medical Biology Centre 97 Lisburn Road Belfast BT9 7BL UK.
authors.forename: A David
authors.initials: AD
authors.lastname: Woolfson
authors.affiliation: Chair in Pharmaceutical Technology School of Pharmacy Queens University Belfast, Medical Biology Centre 97 Lisburn Road Belfast BT9 7BL UK.
authors.forename: Raghu Raj Singh
authors.initials: RR
authors.lastname: Thakur
authors.affiliation: Chair in Pharmaceutical Technology School of Pharmacy Queens University Belfast, Medical Biology Centre 97 Lisburn Road Belfast BT9 7BL UK.
authors.forename: Ryan F
authors.initials: RF
authors.lastname: Donnelly
keywords: crosslinking; hydrogels; microneedle; microwaves; transdermal drug delivery