Full hydrodynamic reversibility of the weak dimerization of vancomycin and elucidation of its interaction with VanS monomers at clinical concentration.

The reversibility and strength of the previously established dimerization of the important glycopeptide antibiotic vancomycin in four different aqueous solvents (including a medically-used formulation) have been studied using short-column sedimentation equilibrium in the analytical ultracentrifuge and model-independent SEDFIT-MSTAR analysis across a range of loading concentrations. The change in the weight average molar mass M with loading concentration was consistent with a monomer-dimer equilibrium. Overlap of data sets of point weight average molar masses M (r) versus local concentration c(r) for different loading concentrations demonstrated a completely reversible equilibrium process.