title: Physical-Chemical Characterization and Formulation Considerations for Solid Lipid Nanoparticles.
abstract: Pure glyceryl mono-oleate (GMO) (lipid) and different batches of GMO commonly used for the preparation of GMO-chitosan nanoparticles were characterized by modulated differential scanning calorimetry (MDSC), cryo-microscopy, and cryo-X-ray powder diffraction techniques. GMO-chitosan nanoparticles containing poloxamer 407 as a stabilizer in the absence and presence of polymers as crystallization inhibitors were prepared by ultrasonication. The effect of polymers (polyvinyl pyrrolidone (PVP), Eudragits, hydroxyl propyl methyl cellulose (HPMC), polyethylene glycol (PEG)), surfactants (poloxamer), and oils (mineral oil and olive oil) on the crystallization of GMO was investigated. GMO showed an exothermic peak at around -10°C while cooling and another exothermic peak at around -12°C while heating. It was followed by two endothermic peaks between 15 and 30 C, indicative of GMO melting. The results are corroborated by cryo-microscopy and cryo-X-ray. Significant differences in exothermic and endothermic transition were observed between different grades of GMO and pure GMO. GMO-chitosan nanoparticles resulted in a significant increase in particle size after lyophilization. MDSC confirmed that nanoparticles showed similar exothermic crystallization behavior of lipid GMO. MDSC experiments showed that PVP inhibits GMO crystallization and addition of PVP showed no significant increase in particle size of solid lipid nanoparticle (SLN) during lyophilization. The research highlights the importance of extensive physical-chemical characterization for successful formulation of SLN.
authors: School of Pharmacy and Health Professions, Creighton University, 2500 California Plaza, Hixson-Lied Science Bldg, #109, Omaha, Nebraska, 68178, USA.
authors: Harsh
authors: H
authors: Chauhan
authors: College of Pharmacy, University of Minnesota, Minneapolis, Minnesota, 55455, USA.
authors: Sarat
authors: S
authors: Mohapatra
authors: School of Pharmacy and Health Professions, Creighton University, 2500 California Plaza, Hixson-Lied Science Bldg, #109, Omaha, Nebraska, 68178, USA.
authors: Daniel J
authors: DJ
authors: Munt
authors: School of Pharmacy and Health Professions, Creighton University, 2500 California Plaza, Hixson-Lied Science Bldg, #109, Omaha, Nebraska, 68178, USA.
authors: Shantanu
authors: S
authors: Chandratre
authors: School of Pharmacy and Health Professions, Creighton University, 2500 California Plaza, Hixson-Lied Science Bldg, #109, Omaha, Nebraska, 68178, USA. adash@creighton.edu.
authors: Alekha
authors: A
authors: Dash
mesh_terms: D002152:Calorimetry, Differential Scanning / Q000379:methods; D055598:Chemical Phenomena; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D008055:Lipids / Q000032:analysis* / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D053758:Nanoparticles / Q000032:analysis* / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D008055:Lipids
keywords: DSC; GMO; aggregation; characterization; crystallization; lipids; lyophilization; polymers; polymorphism; solid lipid nanoparticles; thermal analysis