Indirect enantioseparation of fluoxetine in mouse serum by derivatization with 1R‐(–)‐menthyl chloroformate followed by ultra high performance liquid chromatography and quadrupole time‐of‐flight mass spectrometry

Abstract

Here we describe a simple and sensitive analytical method for the enantioselective quantification of fluoxetine in mouse serum using ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry. The sample preparation method included a simple deproteinization with acetonitrile in 50 μL of serum, followed by derivatization of the extracts in 50 μL of 2 mM 1R-(-)-menthyl chloroformate at 45ºC for 55 min. These conditions were statistically optimized through response surface methodology using a central composite design. Under the optimized conditions, neither racemization nor kinetic resolution occurred. The derivatized diastereomers were readily resolved on a conventional sub-2 μm C18 column under a simple gradient elution of aqueous methanol containing 0.1% formic acid. The established method was validated and found to be linear, precise, and accurate over the concentration range of 5.0-1000.0 ng/mL for both R and S enantiomers (r(2) > 0.993). Stability tests of the prepared samples at three different concentration levels showed that the R- and S-fluoxetine derivatives were relatively stable for 48 h. No significant matrix effects were observed. Last, the developed method was successfully used for enantiomeric analysis of real serum samples collected at a number of time points from mice administered with racemic fluoxetine.

Comprehensive Investigation of the Effects of Brewing Conditions in Sample Preparation of Green Tea Infusions

“…Non-targeted analysis was performed with an Acquity UPLC TM system (Waters Co., Milford, MA, USA) coupled to a Waters Acquity Xevo G2 Q-TOF system (Waters Corp., Manchester, UK), as previously described by our group [40]. For each sample, 5 µL was loaded onto an Agilent ZORBAX Eclipse Plus C 18 column (100 mm × 2.1 mm, 1.8 µm), and a gradient elution of the mobile phase consisting of 0.3% FA in water (A) and 0.3% FA in ACN (B) was performed, as follows: 0–1 min, 5–10% B; 1–10 min, 10–18% B; 10–14 min, 18–100% B; and, 14–17 min, 100% B.…”

Analytical methodologies for the stereoselective determination of fluoxetine: An overview

“…Zhao, Jin, Shin, Jeong, and Lee () developed a method for the enantioselective quantification of FLX in mouse serum using ultra‐high‐performance LC with quadrupole time‐of‐flight MS. The sample preparation method included a simple deproteinization with acetonitrile, followed by derivatization of the extracts with 1 R‐ (−)‐menthyl chloroformate.…”