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

authors	Fonseca, DFS; Costa, PC; Almeida, IF; Dias-Pereira, P; Correia-Sa, I; Bastos, V; Oliveira, H; Duarte-Araujo, M; Morato, M; Vilela, C; Silvestre, AJD; Freire, CSR
nationality	International
journal	CARBOHYDRATE POLYMERS
author keywords	Pullulan; Polysaccharides; Insulin; Microneedles; Transdermal drug delivery
keywords	POLYMER MICRONEEDLES; DELIVERY; NANOPARTICLES; FABRICATION; CELLULOSE; ALGINATE; RELEASE; FILMS; ACID
abstract	The present study reports the fabrication of dissolvable microneedle (MN) patches using pullulan (PL), a watersoluble 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 (T-dmax = 294 degrees C) and mechanical properties (> 0.15 N needle(-1)), penetrating skin up to 381 mu m 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 degrees 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.
publisher	ELSEVIER SCI LTD
issn	0144-8617
isbn	1879-1344
year published	2020
volume	241
digital object identifier (doi)	10.1016/j.carbpol.2020.116314
web of science category	Chemistry, Applied; Chemistry, Organic; Polymer Science
subject category	Chemistry; Polymer Science
unique article identifier	WOS:000539100600049