Designing a unique feedback mechanism for hydrogel-forming microneedle array patches: a concept study
![graphical abstract of Designing a unique feedback mechanism for hydrogel-forming microneedle array patches a concept study](https://www.pharmaexcipients.com/wp-content/uploads/2021/08/Designing-a-unique-feedback-mechanism-for-hydrogel-forming-microneedle-array-patches-a-concept-study.png)
Although microneedle array patch (MAP) technology is reaching ever closer to regulatory approval, it remains imperative that approaches to further improve patient acceptance are still explored. Addressing this perception, a water-filled reservoir was incorporated into a hydrogel-forming MAP system to provide a novel feedback mechanism. To confirm successful MAP skin insertion, the end user would both hear and feel the rupture of the water-filled reservoir.
Interestingly, a 50-µL water-filled reservoir ruptured at 30.27 ± 0.39 N, which has previously been shown as the mean application force for MN insertion in human subjects following appropriate instruction. Importantly, no significant difference in % cumulative permeation of FITC-dextran 10 kDa and fluorescein sodium after 24 h was observed between a 50-µL reservoir and the current method of application that has been successfully used in both in vitro and in vivo studies (p > 0.05).
Therefore, as drug delivery was not affected, this proof-of-concept study has shown that a water-filled reservoir feedback mechanism has the potential to serve as a viable tool for consistent MAP skin insertion.
Download the full article as a PDF here or read it here
Materials: Elastollan® thermoplastic polyurethane pellets with 95A shore hardness (TPU 95A) was generously supplied by DistruPol Ltd, Dublin, Ireland. Fluorescein isothiocyanate–dextran (FITC-dextran 10, MW = 8000–12,000 Da) was purchased from TdB Consultancy AB (Uppsala, Sweden). Fluorescein sodium (MW = 376 Da) and poly(ethylene glycol) (PEG) with MW = 10 000 Da were purchased from Sigma-Aldrich, Dorset, UK. Gantrez® S-97, a co-polymer of methyl vinyl ether and maleic acid (PMVE/MA) was a gift from Ashland, Kidderminster, UK. Sodium carbonate (Na2CO3) was purchased from BDH Laboratory Supplies, London, UK. Pearlitol® 50C-Mannitol was supplied by Roquette, Lestrem, France. Cryogel SG3 was provided by PB Gelatins, Pontypridd, UK.
Article information: Hutton, A.R.J., Kirkby, M., Larrañeta, E. et al. Designing a unique feedback mechanism for hydrogel-forming microneedle array patches: a concept study. Drug Deliv. and Transl. Res. (2021). https://doi.org/10.1007/s13346-021-01033-1