DIBUCAINE INTERACTION WITH PHOSPHOLIPID-VESICLES - A RESONANCE ENERGY-TRANSFER STUDY

• Type: Article in International Scientific Journal
• Date: 1990

Authors

COUTINHO, A (Author) Other; COSTA, J (Author) Other; FARIA, JL (Author) Other; BERBERANSANTOS, MN (Author) Other; PRIETO, MJE (Author) Other

Journal

Title: European Journal of Biochemistry

Vol. 189

Pages: 387-393

ISSN: 0014-2956

Publisher: Blackwell

Indexing

ISI Web of Knowledge - 17 Citations

ISI Web of Science

Scopus - 19 Citations

Scientific classification

FOS: Natural sciences > Biological sciences

Other information

Authenticus ID: P-001-RTM

DOI: 10.1111/j.1432-1033.1990.tb15500.x

Abstract (EN): Resonance energy transfer between a local anaesthetic, dibucaine (donor) and a set of functionalized probes [n-(9-anthroyloxy)stearic acids, n = 2, 3, 6, 7, 9 and 12 and 16-(9-anthroyloxy)palmitic acid] (acceptors) was found to be an efficient process with a critical radius of transfer R0 = 2.1 nm, this interaction being used to locate the drug in a model membrane system, small unilamellar vesicles of dipalmitoylglycerophosphocholine, both above and below the temperature of the gel-to-the-liquid-crystal transition of the phospholipid. From the sequence of relative quenching efficiencies of dibucaine fluorescence upon incorporation of the probes, it was concluded that the drug intercalates in the membrane near the glycerol backborne of the lipid. In addition, it was found that dibucaine location is not significantly affected upon crossing the phase-transition temperature of the phospholipid. Dibucaine photophysics was also studied and the short lifetime of the neutral form of the anaesthetic with respect to that of the monoprotonated species was attributed to an intramolecular charge-transfer interaction. From the study of its partition coefficient between the membrane and the aqueous phase, it was concluded that the only significant species present in the membrane is the charged one.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7