Carbocyanine dyes used as fluorescent triplet probes for measuring slow rotational diffusion of lipids in membranes.
A method for measuring the slow rotational diffusion of lipids or lipid domains in membranes has been developed. It covers the time range from 20 microseconds-5 ms, and has a greater than 5 x 10(4) molecules of probe. The method uses acyl-substituted carbocyanine dyes as fluorescent triplet probes and a laser-microscope combination for excitation and measurement of the triplet state. Rotation rates in dimyristoylphosphatidylcholine vesicles were sensitive to the liquid-to-gel transition. Slow rotations with relaxation times of about 100 microseconds were detected at the transition temperature region.
D002232:Carbocyanines; D005456:Fluorescent Dyes; D008081:Liposomes; D008968:Molecular Conformation; D011804:Quinolines; D013050:Spectrometry, Fluorescence; D013696:Temperature
D002232:Carbocyanines; D005456:Fluorescent Dyes; D008081:Liposomes; D011804:Quinolines