Title

Acid-triggered transformation of diortho ester phosphocholine liposome

Document Type

Article

Publication Title

Journal of the American Chemical Society

ISSN

0002-7863

Volume

128

Issue

1

DOI

10.1021/ja057024w

First Page

60

Last Page

61

Publication Date

12-14-2005

Abstract

The use of pH-sensitive liposomes for acid-triggered site-specific drug delivery is one of the more promising approaches to improve the therapeutic index of drugs. Here, we report the synthesis, assembly, and hydrolysis of the first ortho ester phosphocholine (OEPC). The acid hydrolysis of OEPC liposomes consists of a lag phase and a burst phase. The lag time is pH-dependent—the lower the pH, the shorter the time. Upon acid hydrolysis, the OEPC liposomes were transformed into leaky metastable vesicles that rapidly collapsed in the presence of albumin. OEPC, when formulated with cationic lipid, significantly enhanced the transfection efficiency compared with that of the pH-insensitive formulation.