Design of minocycline-containing starch nanocapsules for topical delivery

Abstract

Pharmaceutical research has been focussed on developing improved delivery systems while exploring new ways of using approved excipients. The present work investigated the potential of starch nanocapsules (StNC) as a topical delivery platform for hydrophilic antimicrobial drugs using minocycline hydrochloride (MH) as a model drug. Thus, a quality by design approach was used to assess the role of different factors that affect the main pharmaceutical properties of StNC prepared using an emulsification–solvent evaporation method. Full characterisation was performed in terms of particle size, encapsulation efficiency, morphology and physical stability at 5 ± 3 °C. Results show the surfactant and lipid contents play a major role in StNC particle size distribution. The MH loading only promoted minor changes upon StNC properties. Formulations were stable without variations on physicochemical properties. All tested formulations presented a zeta-potential of +33.6 ± 6.7 mV, indicating a good physical stability and evidencing that StNC are suitable nanocarriers for topical use.

Keywords:

• Starch
• nanocapsules
• minocycline
• topical application
• skin

Acknowledgements

The authors are grateful to Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal, for the AFM analyses.

Disclosure statement

The authors report no declarations of interest.

Additional information

Funding

This work was supported by the Fundação para a Ciência e a Tecnologia, Portugal (UID/DTP/04138/2013 to iMed.ULisboa and grants SFRH/BDE/51599/2011, SFRH/BD/89520/2012 and SFRH/BSAB/1210/2011) and Laboratórios Atral S.A., Portugal.