Calcium phosphate precipitation in aqueous suspensions of phosphatidylserine-containing anionic liposomes

  title={Calcium phosphate precipitation in aqueous suspensions of phosphatidylserine-containing anionic liposomes},
  author={Edward D. Eanes and Arthur W. Hailer},
  journal={Calcified Tissue International},
SummaryLiposomes prepared from 6.3∶1.8∶0.9∶ 1.0 molar mixtures of phosphatidylcholine, dicetyl phosphate, cholesterol, and phosphatidylserine, respectively, (PS(+) liposomes) were compared with similarly prepared liposomes without the phosphatidylserine (PS(−) liposomes) for their effect on calcium phosphate precipitate formation in aqueous solutions at pH 7.4 and 22°C. The liposomes, encapsulated with 50 mM phosphate (PI), were suspended in buffered 2.2 mM CaCl2, 0 or 1.5 mM KH2PO4 solutions… 

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The conversion of amorphous calcium phosphate to crystalline hydroxyapatite (HA) was studied in vitro in the presence or absence of phosphatidyl serine (PS) and other phospholipids, adding further evidence that lipids may play a role in the control of normal mineralization in vivo.

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