Optimization of the encapsulation efficiency of a novel oral insulin delivery nanosystem

• Main Authors: Carolina Correia, Patrícia Rijo, Lia Ascensão, Marisa Nicolai, Diogo Matias, Catarina Pinto Reis
• Format: Article
• Language: English
• Published: ALIES - Associação Lusófona para o Desenvolvimento da Investigação e do Ensino das Ciências da Saúde 2014-06-01
• Series: Journal Biomedical and Biopharmaceutical Research (BBR)
• Subjects: PLGA; oral insulin nanosystem; multiple emulsion method; encapsulation efficiency
• Online Access: http://www.alies.pt/BBR%20Editions/Vol-11-1-2014/art%204_bf.pdf
• ISSN: 2182-2360; 2182-2379

Oral delivery of insulin may significantly improve the quality of life of diabetes patients who routinely receive insulin by the subcutaneous route. The oral delivery of insulin remains a challenge because of its limited absorption. The main goal of this study was to produce stable nanoparticles with high loads of insulin for further in vivo testing. Poli(lactic-co-glycolic acid) (PLGA), a biodegradable and biocompatible polymer, revealed to be a good presupposition for this approach. Nanoparticles were produced through a multiple emulsion method and the encapsulation efficiency was accessed by a HPLC method. Monodispersed nanoparticles were produced and the insulin EE were improved from 30 % to 65 %, controlling parameters such as the stirring speed rate, volume of external phase, pH range, type of insulin, type of surfactant and polymer concentrations. The nanoparticle size was 398.6 nm with a polydispersivity index of 0.19. The presence of a salt concentration between 20 g L-1 and 50 g L-1 and the type of insulin decreased the size of nanoparticles. Bioactivity assessment after the encapsulation process and full characterization of physical-chemical interactions between all species is now required.