High performance liquid chromatographic determination of moxalactam in human plasma and cerebrospinal fluid

A microscale HPLC-UV method for the determination of latamoxef in plasma: An adapted method for therapeutic drug monitoring in neonates

Latamoxef, a broad-spectrum anti-bacterial agent of the β-lactam antibiotics, is used off-label in treatment of neonatal sepsis. Large inter-individual variability and uncertainty of treatment make therapeutic drug monitoring (TDM) useful to optimize antimicrobial therapy. The objective of this study was to develop and validate a simple, selective and reliable HPLC method for the determination of latamoxef in small volumes of plasma, which could be used in neonatal TDM. After a simple protein precipitation, analytes were separated with liquid chromatography and quantified by UV detection, with tinidazole as the internal standard. The calibration range was linear from 3.0 to 60.0 μg/mL. Intra- and inter-day precisions were < 7.2%. The acceptance criteria of accuracy (between 85 and 115%, 120% for lower limit of quantification) were met in all cases. A plasma volume of 50 μL was required to achieve the limit of quantification of 3.0 μg/mL. The TDM results showed a large variability in trough concentrations. A large number of patients were underdosed, highlighting the unmet need for TDM to optimize latamoxef therapy in neonates.

Determination of third-generation cephalosporins by high-performance liquid chromatography in connection with pharmacokinetic studies

The third-generation cephalosporins are semisynthetic beta-lactam antibiotics, including several oral and parental agents with extended activity against Gram-negative pathogens. They are generally determined either by microbiological techniques or by high-performance liquid chromatography (HPLC). The major drawback or bioassays is the lack of specificity, especially when a biotransformation of the cephalosporin molecule leads to active metabolites, or when the antibacterial therapy is based on association with drugs. Thus, for many years, numerous reversed-phase HPLC procedures have been proposed to overcome these difficulties. This review presents different HPLC methods proposed for the quantification in biological fluids of fourteen third-generation cephalosporins, ranged between parenteral and oral compounds. The sensitivity and specificity of these chromatographic procedures are discussed with regard to the pharmacokinetic properties of the antibiotics studied.