A high sensitivity differential scanning calorimetry study of the interaction between poloxamers and dimyristoylphosphatidylcholine and dipalmitoylphosphatidylcholine liposomes.
High sensitivity differential scanning calorimetry (HSDSC) has been used to measure the thermal behaviour of dimyristoylphosphatidylcholine (DMPC) and dipalmitoylphosphatidylcholine (DPPC) liposomes to which poloxamer surfactants P338 or P407 had been added during or after preparation. The phospholipid pre-transition was more sensitive than the main transition to the association of poloxamers with liposomal bilayers. Poloxamers reduced the enthalpy of the pre-transition of liquid-crystalline state DMPC and DPPC MLVs but not that of gel state DPPC MLVs. Freezing and thawing DMPC and DPPC liposomes in the presence of poloxamers was shown to increase their interaction with the liposomal bilayers.
Castile
J D
JD
Centre for Materials Science, Department of Pharmaceutics, School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, UK.
Taylor
K M
KM
Buckton
G
G
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning / Q000379:methods; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry*; D004347:Drug Interactions; D005615:Freezing; D006361:Heating; D008051:Lipid Bilayers / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry; D020442:Poloxamer / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013535:Suspensions
D008051:Lipid Bilayers; D008081:Liposomes; D013535:Suspensions; D020442:Poloxamer; D015060:1,2-Dipalmitoylphosphatidylcholine; D004134:Dimyristoylphosphatidylcholine