Alexis Guillot1,2,3, Anne-Claude Couffin4,5, Xavier Sejean4,5, Fabrice Navarro4,5, Markus Limberger6,7, Claus-Michael Lehr8,9. 1. PHAST GmbH, Kardinal-Wendel-Str. 16, D-66424, Homburg, Germany. alexis.guillot@phast.com. 2. Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) Helmholtz Center for Infection Research (HZI), Department DDEL, Saarland University, Campus A41, D-66123, Saarbrücken, Germany. alexis.guillot@phast.com. 3. PHAST Development GmbH & Co. KG, Byk-Gulden-Str. 2, Campus Konstanz, D-78467, Constance, Germany. alexis.guillot@phast.com. 4. Univ Grenoble Alpes, F-38000, Grenoble, France. 5. CEA - LETI Minatec, Technologies for Healthcare and Biology Division, 17, rue des Martyrs, F-38054, Grenoble Cedex 09, France. 6. PHAST GmbH, Kardinal-Wendel-Str. 16, D-66424, Homburg, Germany. 7. , Joseph-Haydn-Str. 41, D-66125, Saarbrücken, Germany. 8. Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) Helmholtz Center for Infection Research (HZI), Department DDEL, Saarland University, Campus A41, D-66123, Saarbrücken, Germany. 9. Department of Pharmacy, Saarland University, Campus A41, D-66123, Saarbrücken, Germany.
Abstract
PURPOSE: Contrary to physical characterization techniques for nanopharmaceuticals (shape, size and zeta-potential), the techniques to quantify the free and the entrapped drug remain very few and difficult to transpose in routine analytical laboratories. The application of Solid Phase Extraction (SPE) technique was investigated to overcome this challenge. METHODS: The separation of free and entrapped drug by SPE was quantitatively validated by High Performance Liquid Chromatography. The developed protocol was implemented to characterize cyclosporine A-loaded 120 nm-sized lipid nanoparticles (LNPs, Lipidot®) dispersed in aqueous buffer. The colloidal stability was assessed by Dynamic Light Scattering (DLS). RESULTS: Validation experiments demonstrated suitable linearity, repeatability, accuracy and specificity to quantify residual free, entrapped and total drug. For the investigated LNPs, the method revealed a very limited shelflife of the formulation when stored in an aqueous buffer at 5°C and even more at elevated temperature. Nevertheless, the DLS measurements confirmed the stability of nanoparticles during SPE in a suitable concentration range. CONCLUSIONS: SPE, when successfully validated, represents a valuable tool for drug development and quality control purposes of lipid-based nanopharmaceuticals in an industrial environment.
PURPOSE: Contrary to physical characterization techniques for nanopharmaceuticals (shape, size and zeta-potential), the techniques to quantify the free and the entrapped drug remain very few and difficult to transpose in routine analytical laboratories. The application of Solid Phase Extraction (SPE) technique was investigated to overcome this challenge. METHODS: The separation of free and entrapped drug by SPE was quantitatively validated by High Performance Liquid Chromatography. The developed protocol was implemented to characterize cyclosporine A-loaded 120 nm-sized lipid nanoparticles (LNPs, Lipidot®) dispersed in aqueous buffer. The colloidal stability was assessed by Dynamic Light Scattering (DLS). RESULTS: Validation experiments demonstrated suitable linearity, repeatability, accuracy and specificity to quantify residual free, entrapped and total drug. For the investigated LNPs, the method revealed a very limited shelflife of the formulation when stored in an aqueous buffer at 5°C and even more at elevated temperature. Nevertheless, the DLS measurements confirmed the stability of nanoparticles during SPE in a suitable concentration range. CONCLUSIONS: SPE, when successfully validated, represents a valuable tool for drug development and quality control purposes of lipid-based nanopharmaceuticals in an industrial environment.
Authors: Rachael M Crist; Jennifer Hall Grossman; Anil K Patri; Stephan T Stern; Marina A Dobrovolskaia; Pavan P Adiseshaiah; Jeffrey D Clogston; Scott E McNeil Journal: Integr Biol (Camb) Date: 2013-01 Impact factor: 2.192