Liquid chromatography–tandem mass spectrometry for the determination of paclitaxel in rat plasma after intravenous administration of poly(l-glutamic acid)-alanine-paclitaxel conjugate

An ultrasensitive LC–MS/MS method with liquid phase extraction to determine paclitaxel in both cell culture medium and lysate promising quantification of drug nanocarriers release in vitro

“…This involves cleavage of the O C bond where PTx has been protonated on the ester side chain (E) ( Fig. 2A) accompanied by H rearrangement, to yield m/z 285.95 as the E + 2H ion as reported previously [21][22][23][24][25].…”

“…However, the addition of 0.1% formic acid to the mixture leads to a [M + H] + ion predominance. Further study showed that an acidic 2 mM ammonium acetate/water/ACN buffer, adjusted to pH 3.2 with formic acid, increased the signal-to-noise ratio of [M + H] + and suppressed the Na + adducted ion significantly [21][22][23][24][25]. For PTx, the base peak of the product ion spectrum of the [M + H] + (m/z 854.3) is detected at m/z 285.95.…”

“…Indeed, this technique not only removes potential interferents but also allows concentrating the targeted analytes by solvent evaporation. This process is one of the most commonly used approaches for liquid biological sample preparation [23,27,28,30]. Rapid and simple treatment steps were applied to samples to optimize the extraction process such as proteins precipitation, methanol extraction and cell lysis.…”

“…Indeed, due to its high hydrophobicity, most of in vitro studies of PTx release from nanocarriers were performed in simulated physiological medium supplemented with surfactant Tween 80 [11][12][13][14][15][16][17][18]. Numerous analytical methods using liquid phase extraction and solid phase extraction combined to the LC-MS/MS technique were developed for ultrasensitive quantifi- cation of PTx in biological samples such as cells, plasma, urine, feces or tissues [19][20][21][22][23][24][25][26][27][28][29][30]. Nevertheless, most of the published works use high-performance liquid chromatography or spectrophotometric UV-vis absorbance [11][12][13][14][15]17] and radio labeled [16] detection to determine the in vitro profile of PTx release from nanocarriers.…”

Quantification of a novel natural antioxidant (UP302) in rat plasma using ultra-high performance liquid chromatography–tandem mass spectrometry

“…Extraction recovery was determined by calculating the ratio of the amount of extracted compound from drug-free plasma spiked with known amounts of UP302 to the amount of compound added at the same concentrations to methanol. Matrix effect was evaluated by comparing the mean areas of the post-extraction spiked samples to mean peak areas for neat solutions of UP302 [3]. Stability of UP302 in plasma was assessed using 10 and 800 ng/mL QC samples for short-term temperature, post-preparative and long-term temperature stabilities.…”