Radiation-protective phospholipid and method

• US 5,817,856 A
• Filed: 12/11/1995
• Issued: 10/06/1998
• Est. Priority Date: 12/11/1995
• Status: Expired due to Term

• Current Assignee: Yissum Research Development Company of the Hebrew University of Jerusalem Ltd. (Hebrew University of Jerusalem)
• Original Assignee: Yissum Research Development Company of the Hebrew University of Jerusalem Ltd. (Hebrew University of Jerusalem)
• Inventors: Barenholz, Yechezkel, Tirosh, Oren, Katzhendler, Joshua, Kohen, Ron
• Primary Examiner(s): Raymond, Richard L.
• Application Number:
  US08/570,440
• Time in Patent Office: 1,030 Days
• Field of Search: 558/186, 558/169
• US Class Current: 558/169
• CPC Class Codes: A61K 8/14 Liposomes; Vesicles
• CPC Class Codes: A61K 9/1272 with substantial amounts of non-phosphatidyl, i.e. non-acylglycerophosphate, surfactants as bilayer-forming substances, e.g. cationic lipids with cholesterol as the only non-phosphatidyl surfactant A61K9/127; lipids as modifying agent A61K47/543
• CPC Class Codes: A61Q 17/04 Topical preparations for affording protection against sunlight or other radiation; Topical sun tanning preparations
• CPC Class Codes: C07F 9/10 Phosphatides, e.g. lecithin
• CPC Class Codes: C08G 65/3353 containing oxygen in addition to phosphorus

Abstract

Novel ether-linked phospholipids derivatized with polyethylene glycol at the polar head group are disclosed. Lipid bilayers containing these phospholipids show high oxidative stability. Also disclosed is the use of PEG-derivatized ether-linked lipids in moisturizing and radiation-protective cosmetic compositions.

Claims

1. A dialkyl ether-linked phospholipid having a phosphate containing polar head group, as shown in Formula I:

##STR1## wherein R¹ and R² are hydrocarbon chains containing at least ten carbon atoms,

PEG represents a polyethylene glycol (PEG) chain which has a molecular weight of between about 2,000 and 10,000 daltons,

X is --O^-, alkoxy, amino-alkoxy, or ammonium-alkoxy, and

L is a linker group connecting the phosphate group of the phospholipid to the PEG chain.

2. The phospholipid of claim 1, wherein R¹ and R² are C₁₆ to C₂₄ alkyl or alkenyl chains.

3. The phospholipid of claim 1, wherein the polar head group has a neutral charge.

4. The phospholipid of claim 3, wherein the polar head group includes a lower alkyl phosphate ester.

5. The phospholipid of claim 1, wherein the polar head group has a negative charge.

6. The phospholipid of claim 5, wherein the polar head group includes a phosphate group.

7. The phospholipid of claim 1, wherein the polar head group has a positive charge.

8. The phospholipid of claim 7, wherein the polar head group includes a lower alkyl phosphate ester terminating at a charged amine.

9. The phospholipid of claim 1, wherein the PEG chain has a molecular weight of between 2,000 and 5,000 daltons.