Simple and accurate quantitative analysis of 20 anti-tuberculosis drugs in human plasma using liquid chromatography–electrospray ionization–tandem mass spectrometry

Determination of levofloxacin in human serum using liquid chromatography tandem mass spectrometry

“…The HPLC system was coupled to a triple quadrupole mass spectrometer and quantification was performed in SRM mode with a run time of 2.5 min and retention times of 1.6 min for all the compounds. Our method has advantages over the five studies that have quantified levofloxacin by LC-MS/MS [29][30][31][32][33]. The first study quantified levofloxacin in human urine.…”

“…Ciprofloxacin is available without prescription in many underdeveloped countries and is used for a variety of bacterial infections; therefore, validation of the method using ciprofloxacin as an internal standard could result in the wrong interpretation of analytical results. The third study [29] quantified 20 anti-TB drugs (16 second line including levofloxacin and four first line drugs) in human plasma using LC-MS/ MS but had a long run time of 13 min and used moxifloxacin-d4 as an internal standard for levofloxacin. The fourth study [31] simultaneously quantified azole antifun- gals, antibiotics (levofloxacin and others using levofloxacin-…”

“…Different analytical methods such as capillary electro kinetic chromatography [13][14][15][16], solid phase spectrofluorimetry [17], and high performance liquid chromatography with fluorescent or UV detection [18][19][20][21][22][23][24][25][26][27] have been developed to measure the levofloxacin concentrations in plasma, urine, bile, faeces and other biological fluids [28]. To our knowledge, so far only five studies [29][30][31][32][33] have quantified levofloxacin concentrations by LC-MS/MS; however, among these studies some studies measured levofloxacin in human urine [27], other studies used plasma samples but did not provide description on run time and the ones that did had a relatively long run time and sample preparation time. Therefore, to maximize the efficiency of existing LC-MS/MS methods and further compliment TDM, we aimed to develop and validate a rapid, selective, simple and robust method without extensive sample processing and short run times, to quantify levofloxacin and its metabolite desmethyl-levofloxacin in the serum of MDR-TB patients.…”

“…The last study [33] developed and validated a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the analysis of levofloxacin in serum of MDR-TB patients using enrofloxacin as an internal standard, with a run time and retention time of 4 min and 2.58 min respectively. Two studies [29,33] did not use structural analogue as an internal standard but rather moxifloxacin-d4 and enrofloxacin, which does not have the same retention time and comparable ionization characteristics as levofloxacin [39]. The study by Jourdil et al [31] has advantage over two studies [29,33] in terms of using stable isotopically labeled levofloxacin internal standard.…”

Quantification of isoniazid, pyrazinamide and ethambutol in serum using liquid chromatography-tandem mass spectrometry

“…Recently, Kim et al developed a LC-MS/MS method for the simultaneous quantification of 20 anti-TB drugs. The method consisted of two different precipitation methods, different solid and mobile phases [12]. We successfully applied ultrafiltration as a means of sample preparation for the polar compound ribavirin [13] and we were interested whether this might also be applied for the first-line anti-TB drugs.…”