



@article {3264,
	title = {The impact of nanoparticles on the mucosal translocation and transport of GLP-1 across the intestinal epithelium},
	journal = {Biomaterials},
	volume = {35},
	year = {2014},
	note = {Export Date: 21 November 2014},
	month = {2014},
	pages = {9199 - 9207},
	abstract = {Glucagon like peptide-1 (GLP-1) is an incretin hormone that is in the pipeline for type 2 diabetes mellitus (T2DM) therapy. However, oral administration of GLP-1 is hindered by the harsh conditions of the gastrointestinal tract and poor bioavailability. In this study, three nanosystems composed by three different biomaterials (poly(lactide-co-glycolide) polymer (PLGA), Witepsol E85 lipid (solid lipid nanoparticles, SLN) and porous silicon (PSi) were developed and loaded with GLP-1 to study their permeability invitro. All the nanoparticles presented a size of approximately 200nm. The nanoparticles{\textquoteright} interaction with the mucus and the intestinal cells were enhanced after coating with chitosan (CS). PSi nanosystems presented the best association efficiency (AE) and loading degree (LD), even though a high AE was also observed for PLGA nanoparticles and SLN. Among all the nanosystems, PLGA and PSi were the only nanoparticles able to sustain the release of GLP-1 in biological fluids when coated with CS. This characteristic was also maintained when the nanosystems were in contact with the intestinal Caco-2 and HT29-MTX cell monolayers. The CS-coated PSi nanoparticles showed the highest GLP-1 permeation across the intestinal invitro models. In conclusion, PLGA+CS and PSi+CS are promising nanocarriers for the oral delivery of GLP-1. {\textcopyright} 2014 Elsevier Ltd.},
	keywords = {chitosan, Diabetes, Glucagon like peptide-1, nanoparticles, Oral delivery systems, Triple co-culture},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84906788144\&partnerID=40\&md5=38c557a51eb271561ef59bfe12421842},
	author = {Ara{\'u}jo, F. and Shrestha, N. and Shahbazi, M.-A. and Fonte, P. and M{\"a}kil{\"a}, E.M. and Salonen, J.J. and Hirvonen, J.T. and Granja, P.L. and Santos, H.A. and Sarmento, B.}
}
@article {3281,
	title = {Stability study perspective of the effect of freeze-drying using cryoprotectants on the structure of insulin loaded into PLGA nanoparticles},
	journal = {Biomacromolecules},
	volume = {15},
	year = {2014},
	note = {Export Date: 21 November 2014},
	month = {2014},
	pages = {3753 - 3765},
	abstract = {This work aimed to evaluate the influence of a freeze-drying process using different cryoprotectants on the structure of insulin loaded into poly(lactic-co-glycolic acid) (PLGA) nanoparticles and to assess the stability of these nanoparticles upon 6 months of storage following ICH guidelines. Insulin-loaded PLGA nanoparticles with a size around 450 nm were dehydrated using a standard freeze-drying cycle, using trehalose, glucose, sucrose, fructose, and sorbitol at 10\% (w/v) as cryoprotectants. All formulations, except those nonadded of cryoprotectant and added with trehalose, collapsed after freeze-drying. The addition of cryoprotectants increased the nanoparticles stability upon storage. FTIR results showed that insulin maintained its structure after encapsulation in about 88\%, decreasing to 71\% after freeze-drying. The addition of cryoprotectants prior to freeze-drying increased insulin structural stability an average of up to 79\%. Formulations collapsed after freeze-drying showed better protein stabilization upon storage, in special sorbitol added formulation, preserving 76, 80, and 78\% of insulin structure at 4 {\textdegree}C, 25 {\textdegree}C/60\% RH, and 40 {\textdegree}C/75\% RH, respectively. Principal component analysis also showed that the sorbitol-added formulation showed the most similar insulin structural modifications among the tested storage conditions. These findings suggested that regarding nanoparticles stability, cryoprotectants are versatile to be used in a standard freeze-drying, however they present different performances on the stabilization of the loaded protein. Thus, on the freeze-drying of the nanoparticles field, this work gives rise to the importance of the process of optimization, searching for a balance between a good obtainable cake with an optimal structural stabilization of the loaded protein.},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84907968489\&partnerID=40\&md5=15b0a74cf97f04ed887f86b7ad1c45a2},
	author = {Fonte, P. and Soares, S. and Sousa, F. and Costa, A. and Seabra, V. and Reis, S. and Sarmento, B.}
}
@article {2845,
	title = {Effect of freeze-drying, cryoprotectants and storage conditions on the stability of secondary structure of insulin-loaded solid lipid nanoparticles},
	journal = {International Journal of Pharmaceutics},
	volume = {456},
	year = {2013},
	note = {Export Date: 12 December 2013Source: Scopus},
	month = {2013///},
	pages = {370 - 381},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84886730036\&partnerID=40\&md5=2214d57803df6679f944d2ebba4fa477},
	author = {Soares, S. and Fonte, P. and Costa, A. and Andrade, J. and Seabra, V. and Ferreira, D. and Reis, S. and Sarmento, B.}
}
