Autor(es): Fonseca, Daniela F. S. ; Costa, Paulo C. ; Almeida, Isabel F. ; Dias-Pereira, Patrícia ; Correia-Sá, Inês ; Bastos, Verónica ; Oliveira, Helena ; Duarte-Araújo, Margarida ; Morato, Manuela ; Vilela, Carla ; Silvestre, Armando J. D. ; Freire, Carmen S. R.
Data: 2020
Identificador Persistente: http://hdl.handle.net/10773/37708
Origem: RIA - Repositório Institucional da Universidade de Aveiro
Assunto(s): Pullulan; Polysaccharides; Insulin; Microneedles; Transdermal drug delivery
The present study reports the fabrication of dissolvable microneedle (MN) patches using pullulan (PL), a water-soluble polysaccharide with excellent film-forming ability, for the transdermal administration of insulin, envisioning the non-invasive treatment of diabetes. PL MNs patches were successfully prepared by micromoulding and revealed good thermal stability (Tdmax = 294 °C) and mechanical properties (>0.15 N needle-1), penetrating skin up to 381 μm depth, as revealed by in vitro skin tests. After application into human abdominal skin in vitro, the MNs dissolved within 2 h releasing up to 87% of insulin. When stored at 4, 20 and 40 °C for 4 weeks, insulin was able to retain its secondary structure, as shown by circular dichroism spectropolarimetry. The prepared PL MNs were non-cytotoxic towards human keratinocytes, being suitable for skin application. These findings suggest that PL MNs have potential to deliver insulin transdermally, thus avoiding its subcutaneous administration.
