Absence in amphotericin B-spiked human plasma of the free monomeric drug, as detected by SERS.
Using surface enhanced Raman spectroscopy (SERS) which enables us to specifically detect traces of monomeric amphotericin B (AmB), we were able to show that in a 10(-5) M AmB suspension, the concentration of free drug was below 10(-8) M in the presence of low density lipoproteins (LDL) or plasma. The affinity constant of AmB for LDL determined from electronic absorption data, was found to be 4 x 10(6) M(-1). Therefore, since AmB appears to be in the majority bound to lipoproteins under in vivo conditions, its toxicity should not result from the induction of host-cell transmembrane permeability but rather from the internalization of the AmB-LDL complex.
Ridente
Y
Y
Laboratoire de Physicochimie Biomoléculaire et Cellulaire (LPBC) (ESA CNRS 7033), Université Pierre et Marie Curie, Paris, France.
Aubard
J
J
Bolard
J
J
D000042:Absorption; D000666:Amphotericin B / Q000493:pharmacokinetics*; D002942:Circular Dichroism; D006801:Humans; D010949:Plasma; D013059:Spectrum Analysis, Raman / Q000379:methods; D014466:Ultraviolet Rays
D000666:Amphotericin B