An Investigation on the Analytical Potential of Polymerized Liposomes bound to Lanthanide Ions for Protein Analysis

M. SANTOS, B. ROY, H. GOICOECHEA, A. CAMPIGLIA AND S. MALIK

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

American Chemical Society

Lugar: New York; Año: 2004 p. 10738 - 10745

0002-7863

We present a promising approach to protein sensing based on Eu3+ ions incorporated into polymerized liposomes. The sensitization of Eu3+ is accomplished with 5-aminosalysilic acid, which provides energy transfer for a stable reference signal and a wide wavelength excitation range free from protein interference. The lipophilic character of polymerized liposomes provides the appropriate platform for protein interaction with the lanthanide ion. Quantitative analysis is based on the linear relationship between the luminescence signal of Eu3+ and protein concentration. Because no spectral shift of the lanthanide luminescence is observed upon protein interaction, qualitative analysis is based on the luminescence lifetime of polymerized liposomes. This parameter, which changes significantly upon protein-liposome interaction, follows a well behaved single exponential decay that might be useful for protein identification