Protonation equilibrium and lipophilicity of moxifloxacin.
This study was performed to characterise the protonation equilibrium at the molecular level and pH-dependent lipophilicity of moxifloxacin. After determining macro- and micro-constants, distribution features of four microspecies in aqueous phase were assessed. The apparent partition coefficient versus pH profile of moxifloxacin showed a parabolic curve in n-octanol/buffer system which reached near pI. The true partition coefficient was calculated from the log P(app) and microconstants values.
Langlois
Marie-Hélène
MH
Laboratory of Analytical Chemistry, EA 2962, Bordeaux Il University, Bordeaux, France.
Montagut
Martine
M
Dubost
Jean-Pierre
JP
Grellet
Jean
J
Saux
Marie-Claude
MC
D020003:1-Octanol; D001372:Aza Compounds / Q000737:chemistry*; D002021:Buffers; D024841:Fluoroquinolones; D006863:Hydrogen-Ion Concentration; D008055:Lipids / Q000737:chemistry*; D008956:Models, Chemical; D000077266:Moxifloxacin; D011522:Protons; D011804:Quinolines / Q000737:chemistry*; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet
D001372:Aza Compounds; D002021:Buffers; D024841:Fluoroquinolones; D008055:Lipids; D011522:Protons; D011804:Quinolines; D012996:Solutions; D020003:1-Octanol; D000077266:Moxifloxacin