Hydrogel-Forming Microneedle Arrays Allow Detection of Drugs and Glucose In Vivo: Potential for Use in Diagnosis and Therapeutic Drug Monitoring - Fig 2

(A) Schematic representation of casting and crosslinking of hydrogel film formulations. (B) Diagrammatic representation of steps involved in the preparation of polymeric MNs. Polymer matrix was transferred to the silicone mould (i). The mould was centrifuged at 3000 rpm for 15 minutes (ii). Upon drying and heating for 24 h at 80°C to induce ester-based crosslinking, the silicone mould was carefully peeled away from the polymeric MN array and side walls removed using a hot scalpel blade (iii). Digital photograph image of MN with side walls (iv). Digital image of MN after removing the side walls using hot scalpel blade (v). (C) Illustration of the modified Franz cell apparatus used to investigate MN uptake of analytes across excised dermatomed neonatal porcine skin in vitro.