Quantitative determination of colistin A/B and colistin methanesulfonate in biological samples using hydrophilic interaction chromatography tandem mass spectrometry

Abstract

Colistin (polymyxin E) is a polycation antibiotic which is increasingly used (administered as colistin methanesulfonate, CMS) as a salvage therapy in critically ill patients with multidrug resistant Gram‐negative infections. Even though colistin has been used for more than 50 years, its metabolic fate is poorly understood. One of the current challenges for studying the pharmacokinetics (PK) is the precise and accurate determination of colistin in in vitro and in vivo studies. In the present study, we developed and validated a series of sensitive and robust liquid chromatography tandem mass spectrometry (LC–MS/MS) methods for analysing biological samples obtained from in vitro and in vivo disposition assays. After a zinc acetate‐mediated precipitation, hydrophilic–lipophilic‐balanced solid phase extraction (HLB‐SPE) was used for the extraction of colistin. The compounds were retained on a hydrophilic interaction liquid chromatography (HILIC) column and were detected by MS/MS. CMS was quantified by determining the produced amount of colistin during acidic hydrolysis. The developed methods are sensitive with lower limits of quantification varying between 0.009 μg/mL and 0.071 μg/mL for colistin A, and 0.002 μg/mL to 0.013 μg/mL for colistin B. The intra‐ and inter‐day precision and accuracy were within ±15%. Calibration curves of colistin were linear (0.063 μg/mL to 8.00 μg/mL) within clinically relevant concentration ranges. Zinc acetate‐mediated precipitation and the use of a HILIC column were found to be essential. The developed methods are sensitive, accurate, precise, highly efficient and allow monitoring colistin and CMS in biological samples without the need for an internal standard.

Dissemination and prevalence of polymyxin-resistant bacteria of clinical and environmental origin

“…Colistin is a prodrug used in the form of Colistimethate Sodium (CMS), which after being metabolized is converted to colistin, while polymyxin B is used in the form of sulfated salt. Therefore, despite being similar in spectrum of action, these drugs have different pharmacokinetic profiles (Bialvaei & Kafil, 2015;Wenzler et al, 2016;Qi et al, 2020;Wallace et al, 2010).…”

Salvage parenteral antibiotics for multidrug‐resistant (MDR) Gram‐negative bacteria; a fluorescamine‐based technique for ultrasensitive spectrofluorimetric measurement of Polymyxins; human plasma application

“…Considering spectroscopic methods, few ultraviolet (UV) spectrophotometric [ 8–12 ] and just two fluorimetric publications [ 13,14 ] , one for each antibiotic, have been reported previously. Furthermore, several chromatographic techniques such as high performance liquid chromatography (HPLC), [ 15–23 ] liquid chromatography (LC), [ 24–33 ] thin layer chromatography (TLC), [ 10,34 ] ultrahigh performance liquid chromatography (UPLC) [ 35–37 ] , and electrophoretic techniques [ 38–41 ] have been published. Conversely, microbiological assays [ 42–44 ] have been reported.…”

“…techniques such as high performance liquid chromatography (HPLC), [15][16][17][18][19][20][21][22][23] liquid chromatography (LC), [24][25][26][27][28][29][30][31][32][33] thin layer chromatography (TLC), [10,34] ultrahigh performance liquid chromatography (UPLC) [35][36][37] , and electrophoretic techniques [38][39][40][41] have been published. Conversely, microbiological assays [42][43][44] have been reported.…”

HPLC Determination of Colistin in Human Urine Using Alkaline Mobile Phase Combined with Post-Column Derivatization: Validation Using Accuracy Profiles

“…The advantages and disadvantages of these approaches in terms of cost, instrumentation, matrix interferences, and sensitivity are more or less well known, and they were adequately discussed in a recent dedicated review article by Gikas and coworkers [ 3 ]. Mass spectrometric detection techniques are always attractive in bioanalysis, and there have been several very recent reports on the analysis of Colistin in rats [ 9 , 10 ] or human plasma [ 11 ], intestinal matrices of poultry [ 12 , 13 , 14 ], and eggs [ 15 ]. Sample preparation prior to LC–MS analysis varies from simple protein precipitation [ 9 ] to solid-phase extraction using advanced cation exchange or hydrophilic/lipophilic balance (HLB) materials [ 10 , 14 ].…”