Wavelength-programmed solute release from photosensitive liposomes.
Liposomes of dipalmitoylphosphatidylcholine containing a photochromic lipid "Bis-Azo PC" release entrapped solutes on exposure to UV light. We have now demonstrated that on addition of cholesterol (up to 25 mol%) to the liposomal membrane the liposomes also release their contents in response to visible light in the region of 470 nm, to which liposomes lacking steroid are insensitive. In a mixed population of liposomes prepared with and without cholesterol, this enables wavelength-dependent release of entrapped solutes on sequential exposure to visible and UV light. Furthermore, the cholesterol-containing liposomes allow stepped partial release of entrapped solute following multiple periods of short visible illumination. It is suggested that the cholesterol-containing liposomes may be potentially useful for drug delivery and for "caging" of reagents.
Bisby
R H
RH
Division of Biological Sciences, School of Environmental and Life Sciences, University of Salford, Salford M5 4WT, United Kingdom. r.h.bisby@salford.ac.uk
Mead
C
C
Morgan
C G
CG
D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol; D004337:Drug Carriers; D016503:Drug Delivery Systems; D008027:Light; D008081:Liposomes; D010775:Photic Stimulation
D004337:Drug Carriers; D008081:Liposomes; D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol