Physical and photophysical characterization of a BODIPY phosphatidylcholine as a membrane probe

Biophys J. 2002 Sep;83(3):1511-24. doi: 10.1016/S0006-3495(02)73921-0.


Lipids containing the dimethyl BODIPY fluorophore are used in cell biology because their fluorescence properties change with fluorophore concentration (C.-S. Chen, O. C. Martin, and R. E. Pagano. 1997. Biophys J. 72:37-50). The miscibility and steady-state fluorescence behavior of one such lipid, 1-palmitoyl-2-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-pentanoyl)-sn-glycero-3-phosphocholine (PBPC), have been characterized in mixtures with 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine (SOPC). PBPC packs similarly to phosphatidylcholines having a cis-unsaturated acyl chain and mixes nearly ideally with SOPC, apparently without fluorophore-fluorophore aggregation. Increasing PBPC mole fraction from 0.0 to 1.0 in SOPC membranes changes the emission characteristics of the probe in a continuous manner. Analysis of these changes shows that emission from the excited dimethyl BODIPY monomer self quenches with a critical radius of 25.9 A. Fluorophores sufficiently close (< or =13.7 A) at the time of excitation can form an excited dimer, emission from which depends strongly on total lipid packing density. Overall, the data show that PBPC is a reasonable physical substitute for other phosphatidylcholines in fluid membranes. Knowledge of PBPC fluorescence in lipid monolayers has been exploited to determine the two-dimensional concentration of SOPC in unilamellar, bilayer membranes.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Biophysical Phenomena
  • Biophysics
  • Boron Compounds / chemistry*
  • Cell Membrane / metabolism*
  • Lipid Bilayers / chemistry
  • Models, Theoretical
  • Phosphatidylcholines / chemistry*
  • Pressure
  • Spectrometry, Fluorescence
  • Temperature


  • 1-palmitoyl-2-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-pentanoyl)-sn-glycero-3-phosphocholine
  • 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene
  • Boron Compounds
  • Lipid Bilayers
  • Phosphatidylcholines