TABLE 1.

Determined MICs (presented as modes) and simultaneously fitted model parameters (± standard deviations) of ceftriaxone and ertapenem against E. coli and S. pneumoniae in the presence and absence of BSA and HSA

Antibiotic, strain, and protein supplementaParameter
MIC (μg/ml)ks (h−1)kmax (h−1)EC50 (μg/ml)hMSC
Ceftriaxone
    E. coli ATCC 25922
        Without albumin0.0642.40 (±0.34)6.34 (±0.13)0.027d (±0.0007)1.61 (±0.10)4.24
        With BSA0.0640.057d (±0.007)
        With HSA21.096b,c (±0.0272)
    S. pneumoniae ATCC 6303
        Without albumin0.011.56 (±0.08)3.59 (±0.11)0.004d (±0.0004)2.18 (±0.14)4.04
        With BSA0.020.015d (±0.0099)
        With HSA0.160.084b,c (±0.0147)
Ertapenem
    E. coli ATCC 25922
        Without albumin0.0152.76 (±0.89)6.02 (±1.00)0.010 (±0.0035)2.54 (±0.14)4.71
        With BSA0.0150.020 (±0.0029)
        With HSA0.030.014 (±0.0046)
    S. pneumoniae ATCC 6303
        Without albumin0.0252.28 (±0.13)3.28 (±0.11)0.010 (±0.0019)2.65 (±0.25)2.67
        With BSA0.0250.010 (±0.0015)
        With HSA0.0250.019 (±0.0101)
  • a BSA and HSA were added at a protein concentration of 40 g/liter.

  • b Significant difference (P ≤ 0.05) from the value for the control (protein-free).

  • c Significant difference (P ≤ 0.05) from the value for the sample with BSA.

  • d Significant difference (P ≤ 0.05) from the value for the sample with HSA.