title: Using in situ Raman spectroscopy to study the drug precipitation inhibition and supersaturation mechanism of Vitamin E TPGS from self-emulsifying drug delivery systems (SEDDS).
abstract: We are reporting a new methodology of using Raman spectroscopy for studying the drug surfactant interactions in self-emulsifying drug delivery systems (SEDDS). The physicochemical properties of surfactants could affect the performance of drugs from lipid delivery systems. Thus the purpose of our research was to study the drug surfactant interactions on a molecular level to understand the mechanism of supersaturation and precipitation inhibition. Two surfactants, Labrasol® and Vitamin E TPGS, were used to formulate several SEDDS. The optimized SEDDS were further evaluated by a kinetic solubility study and in situ Raman spectroscopy for two model drugs. It was found that both drugs precipitated from Labrasol® SEDDS whereas TPGS was able to inhibit precipitation and achieve high drug supersaturation levels. In situ Raman spectroscopy indicated that hydrogen bonding with TPGS was the main factor responsible for inhibiting precipitation. This study was able to correlate the structure and physicochemical properties of the drugs and surfactants to their ability to prevent drug precipitation. Our study brings up a possible new systematic approach by using Raman spectroscopy in the development and optimization of lipid based delivery systems.
authors.affiliation: School of Pharmacy Boston, MCPHS University, 179 Longwood Avenue, Boston, MA 02115, United States. Electronic address: sraut84@gmail.com.
authors.forename: Shilpa
authors.initials: S
authors.lastname: Raut
authors.affiliation: School of Pharmacy Boston, MCPHS University, 179 Longwood Avenue, Boston, MA 02115, United States.
authors.forename: Basel
authors.initials: B
authors.lastname: Karzuon
authors.affiliation: School of Pharmacy Boston, MCPHS University, 179 Longwood Avenue, Boston, MA 02115, United States; California Northstate University College of Pharmacy, Elk Grove, CA 95757, United States.
authors.forename: Eman
authors.initials: E
authors.lastname: Atef
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis; D000924:Anticholesteremic Agents / Q000032:analysis; D004337:Drug Carriers; D016503:Drug Delivery Systems; D004655:Emulsions; D006860:Hydrogen Bonding; D007213:Indomethacin / Q000032:analysis; D007700:Kinetics; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000737:chemistry; D011341:Probucol / Q000032:analysis; D013059:Spectrum Analysis, Raman; D014810:Vitamin E / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000924:Anticholesteremic Agents; D004337:Drug Carriers; D004655:Emulsions; D014810:Vitamin E; D011092:Polyethylene Glycols; C014225:tocophersolan; D011341:Probucol; D007213:Indomethacin
keywords: Indomethacin; Probucol; Raman spectroscopy; SEDDS; Vitamin E TPGS