Pullulan microneedle patches for the efficient transdermal administration of insulin envisioning diabetes treatment

• Autor(a) principal: Fonseca, Daniela F. S.
• Data de Publicação: 2020
• Outros Autores: 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.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/37708
• topic: 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.