Retention of structurally diverse drugs in human serum albumin chromatography and its potential to simulate plasma protein binding.
The retention behavior of 39 structurally diverse neutral, basic and acidic drugs was investigated on an HSA stationary phase using PBS buffer (pH 7.0) and acetonitrile or 2-propanol as organic modifiers. Extrapolated or directly measured logk(w) values as well as isocratic retention factors were correlated with plasma protein binding data taken from the literature. Retention factors determined in the presence of 10% acetonitrile led to high quality 1:1 correlation with apparent logK(HSA) values. The derived reference equation was successfully validated using a secondary set of 24 drugs. Further analysis of HSA retention into more fundamental properties revealed the involvement of anionic species in solute-stationary phase interactions, expressed by the negatively charged fraction, besides the partitioning mechanism which was reflected by lipophilicity. Protonation of basic drugs, although less important, may also influence retention, leading to reduced partitioning into the HSA surface as a net effect, while it seems to have no effect on HSA binding. The above results were further confirmed by linear solvation energy relationships (LSER).
Chrysanthakopoulos
Marios
M
Department of Pharmaceutical Chemistry, School of Pharmacy, University of Athens, Panepistimiopolis, Zografou, Athens 15771, Greece.
Giaginis
Costas
C
Tsantili-Kakoulidou
Anna
A
D019840:2-Propanol / Q000737:chemistry; D000097:Acetonitriles / Q000737:chemistry; D001798:Blood Proteins / Q000737:chemistry / Q000378:metabolism*; D002853:Chromatography, Liquid / Q000379:methods*; D055808:Drug Discovery; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008968:Molecular Conformation; D004364:Pharmaceutical Preparations / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D012044:Regression Analysis; D015203:Reproducibility of Results; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism*; D013816:Thermodynamics
D000097:Acetonitriles; D001798:Blood Proteins; D004364:Pharmaceutical Preparations; D012709:Serum Albumin; D019840:2-Propanol; C032159:acetonitrile