In vitro protein binding of teicoplanin to neonatal serum

The protein-binding ability of teicoplanin (TEIC) to neonatal serum was investigated and the following results were obtained. (1) The protein binding ability of TEIC at concentrations ranging from 10 to 100 μg/ml, to neonatal serum was 80.5%-71.9% and was generally low as compared with that for adult serum. (2) The protein binding ability of TEIC (20 μg/ml) to albumin in neonatal serum was not concentration-dependent, and the correlation between the protein-binding ability and albumin concentration was low. Namely, it was suggested that the protein-binding ability of TEIC to neonatal serum was not dependent merely on the albumin concentration, and there was a possibility that the protein-binding ability also depended on qualitative changes in albumin. (3) The protein-binding ability of TEIC (20 μg/ml) to total bilirubin and free bilirubin was not concentration-dependent, and the correlation was extremely low, indicating that there is a low possibility that the protein-binding ability of TEIC induces an increase in free bilirubin.