Biomaterial Database

Calcium-induced aggregation of phosphatidylcholine vesicles containing free oleic acid. 1988

A Ortiz, and J C Gomez-Fernandez

Departamento de Bioquímica, Facultad de Veterinaria, Universidad de Murcia, Spain.

Small unilamellar vesicles (SUV) formed by egg yolk phosphatidylcholine (PC) and free oleic acid (OA) undergo aggregation induced by Ca2+ at pH greater than 7.0. The rate of the process, as monitored by turbidity changes, presents a linear dependence on phospholipid concentration and a hyperbolic dependence on Ca2+ concentration. The aggregation curves show a lag period which is tentatively attributed to an activation step induced by Ca2+. The incorporation of either cholesterol, alpha-tocopherol or egg yolk phosphatidylethanolamine (PE) produced a decrease in the aggregation rate and an increase in the lag period. Fusion was not detected in any of the different experiments, either by the assay of mixing the membrane phospholipids or by the assay of mixing the aqueous contents. A possible mechanism, explaining the aggregation process is proposed.

UI	MeSH Term	Description	Entries
D008081	Liposomes	Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.	Niosomes,Transferosomes,Ultradeformable Liposomes,Liposomes, Ultra-deformable,Liposome,Liposome, Ultra-deformable,Liposome, Ultradeformable,Liposomes, Ultra deformable,Liposomes, Ultradeformable,Niosome,Transferosome,Ultra-deformable Liposome,Ultra-deformable Liposomes,Ultradeformable Liposome
D009829	Oleic Acids	A group of fatty acids that contain 18 carbon atoms and a double bond at the omega 9 carbon.	Octadecenoic Acids,Acids, Octadecenoic,Acids, Oleic
D010713	Phosphatidylcholines	Derivatives of PHOSPHATIDIC ACIDS in which the phosphoric acid is bound in ester linkage to a CHOLINE moiety.	Choline Phosphoglycerides,Choline Glycerophospholipids,Phosphatidyl Choline,Phosphatidyl Cholines,Phosphatidylcholine,Choline, Phosphatidyl,Cholines, Phosphatidyl,Glycerophospholipids, Choline,Phosphoglycerides, Choline
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation