Phospholipid hydrolysis in a pharmaceutical emulsion assessed by physicochemical parameters and a new analytical method.
The aim of this work was to develop a simple high-performance liquid chromatography (HPLC) technique with evaporative light scattering detection (ELSD) for the separation and quantification of the major phospholipid (PL) and lysophospholipid (LPL) classes contained in a pharmaceutical phospholipid-based emulsion. In the established method, phosphatidylcholine (PC), phosphatidylethanolamine (PE), sphingomyeline (SM), lysophosphatidylcholine (LPC) and lysophosphatidylethanolamine (LPE) were separated with a PVA-Sil stationary phase and a binary gradient from pure chloroform to methanol:water (94:6 v/v) at 3.4%/min. The ELSD detection was enhanced using 0.1% triethylamine and formic acid in each gradient mobile phases. Factors such as stationary phase and ELSD drift tube temperature were optimized, concluding in optimal temperatures of 25 degrees C for separation and 50 degrees C for evaporation. This HPLC-ELSD method was then applied to a PL-emulsion exposed to autoclaving and accelerated thermal conditions at 50 degrees C. Hydrolysis of PC and PE followed first-order kinetics, representing only 45% of the total lipid mass after 3 months. The chemical stability was correlated to commonly measured formulation physical and physico-chemical parameters such as droplet size, emulsion pH and zeta-potential.
Rabinovich-Guilatt
Laura
L
UMR CNRS 8612, School of Pharmacy, Châtenay Malabry, France.
Dubernet
Catherine
C
Gaudin
Karen
K
Lambert
Gregory
G
Couvreur
Patrick
P
Chaminade
Pierre
P
D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D004655:Emulsions; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D004364:Pharmaceutical Preparations / Q000032:analysis*; D010743:Phospholipids / Q000302:isolation & purification*; D012015:Reference Standards; D013696:Temperature
D004655:Emulsions; D004364:Pharmaceutical Preparations; D010743:Phospholipids