Determination of Vancomycin in Human Plasma, Bone and Fat by Liquid Chromatography/Tandem Mass Spectrometry

Abstract

A liquid chromatography/tandem mass spectrometry (LC-MS/MS) assay was developed for the determination of vancomycin in human plasma, bone and fat tissue. For vancomycin in plasma, sample was treated with methanol to precipitate the proteins. After centrifugation, the supernatant was diluted with water, and then injected into the LC-MS/MS system. For vancomycin in bone and fat, the pulverized bone/fat samples were immersed in phosphate buffered saline pH 7.3 at 4°C overnight. After centrifugation, the supernatant of bone/fat tissue suspension was treated in the same way as the plasma samples. Vancomycin and aminopterin, the internal standard, were resolved on a C18(2) column using gradient elution of 0.05% formic acid and methanol. The two compounds were detected using electrospray ionisation in the positive mode. Standard curves were linear over the concentration range 0.05 to 50 mg/L (r

Impacts of solids retention time and antibiotic loading in activated sludge systems on secondary effluent water quality and microbial community structure

“…Samples were immediately placed on ice and held at 4°C for up to 14 days until further processing, which consisted of filtration with 0.7‐μm glass fiber filters (GF/F; Whatman) and automated online solid phase extraction. The samples were then analyzed for the target compounds by liquid chromatography–tandem mass spectrometry (LC‐MS/MS) with isotope dilution according to previously published methods (Lopes et al., ; Vanderford, Pearson, Rexing, & Snyder, ; Vanderford & Snyder, ; Zhang, Moore, & Young, ). Method reporting limits (MRLs) were established at 3–5 times the method detection limits and ranged from 5 ng/L to 10,000 ng/L depending on the target compound, sample matrix, and dilution.…”

Overview of the analytical methods for vancomycin and/or teicoplanin determination in biological matrices

“…Protein precipitation is a simple, cost-effective, efficient, and timesaving method which includes removing proteins from the sample by denaturing them with appropriate organic solvent or acid followed by centrifugation. Protein precipitation was the method of choice for preparation of samples containing vancomycin or teicoplanin (Javorska et al, 2017;Begou et al, 2017;Sheng & Zhou, 2017;Brozmanová et al, 2017;Wicha & Kloft, 2016;Oyaert et al, 2015;Cao et al, 2014;Zhang et al, 2014b;Bijleveld et al, 2014;Cazorla-Reyes et al, 2014). Acetonitrile is frequently used as a precipitation agent for preparing plasma, serum, urine or peritoneal/pleural effusion containing vancomycin, and plasma or serum containing teicoplanin, giving a good extract purity (Oyaert et al, 2015;Cao et al, 2014, Javorska et al, 2017Cazorla-Reyes et al, 2014, Begou et al, 2017Cazorla-Reyes et al, 2014).…”

“…Serum samples were prepared using 33% trichloroacetic acid as a precipitation agent and 0.5 mol L -1 ammonium hydroxide in order to increase pH value (Brozmanová et al, 2017). Methanol as a protein precipitation agent was used for determination of vancomycin in human plasma, bone or fat tissue, where the extraction recovery was approximately 100%, and in bacterial growth medium (Zhang et al, 2014b;Wicha & Kloft, 2016). The main disadvantage of protein precipitation as a sample preparation method is that matrix components other than proteins can remain in the sample, so it is of great importance to find optimal precipitation agents, optimal values of centrifugation parameters, and sample:precipitation agent ratios.…”

“…For determination of vancomycin and teicoplanin, isocratic or gradient elution modes have been applied (Zhang et al, 2014a, Javorska et al, 2017Begou et al, 2017;Sheng & Zhou, 2017;Brozmanová et al, 2017;Kim et al, 2016;Wicha & Kloft, 2016;Oyaert et al, 2015;Cao et al, 2014;Zhang et al, 2014b;Bijleveld et al, 2014;Li et al, 2014;Cazorla-Reyes et al, 2014). In isocratic mode, phosphate buffer was mixed with acetonitrile for the analysis of vancomycin, and analysis time was 10 min (Zhang et al, 2014a).…”

“…Matrix components influence the ionization efficiency in the ionization source, reducing the sensitivity of the method. Techniques commonly used for sample preparation include protein precipitation (PP), liquid-liquid extraction (LLE) solid-phase extraction (SPE), and in this review their application for sample treatment for the two glycopeptide antibiotics is presented (Javorska et al, 2017;Begou et al, 2017;Kim et al, 2016;Sheng & Zhou, 2017;Brozmanová et al, 2017;Wicha & Kloft, 2016;Oyaert et al, 2015;Cao et al, 2014;Cazorla-Reyes et al, 2014;Zhang, 2014a;Zhang et al, 2014b;Bijleveld et al, 2014;Li et al, 2014).…”