Determination of ceftriaxone concentration in human cerebrospinal fluid by high-performance liquid chromatography with UV detection

Determination of ceftriaxone (CTRX) concentration in human cerebrospinal fluid (CSF) is required to clarify whether a high concentration of CTRX in CSF is associated with CTRX-induced encephalopathy (CIE). In our study, in order to perform an accurate analysis of CSF sample from CIE patient, we proposed HPLC with UV detection (HPLC-UV) using an octadecylsilica (ODS) column, a methanol and 10 mM phosphoric acid (25:75, v/v) mixture solution as a mobile phase, and a detection wavelength at 280 nm. The linear range was from 0.1 to 100 mu g/mL (r = 0.999) in the present HPLC-UV. In the recovery tests using blank samples of human CSF and control serum spiked with CTRX, the recoveries of CTRX were > 95.3%, and the RSD (n = 3) was < 5.8%. We applied the proposed HPLC-UV system to determine CTRX in the CSF and serum samples obtained from a patient diagnosed as having CIE, and it was revealed that the CTRX concentrations in the CSF sample and the serum were 2.61 and 37.35 mu g/mL, respectively. To the best of our knowledge, this is the first report describing the determination of CTRX concentration in a CSF sample obtained from a peritoneal dialysis patient diagnosed as having CIE.