Development and Validation of Chemometrics-Assisted Green UPLC-MS/MS Bioanalytical Method for Simultaneous Estimation of Capecitabine and Lapatinib in Rat Plasma

A chemometrics-oriented green ultra-performance liquid chromatography-mass spectrometry/mass spectrometry method was developed and validated for the first-time simultaneous estimation of capecitabine (CAP) and lapatinib (LPB) along with imatinib (as internal standard (IS)) in rat plasma. Analytes were extracted using ethyl acetate as the liquid-liquid extraction media. In the pre-development phase, principles of analytical eco-scale were used to confirm method greenness. Subsequently, vital method variables, influencing method robustness and performance, were optimized using a chemometrics-based quality-by-design approach. Chromatography was achieved on a BEH C18 (100 × 2.1 mm, 1.7 μm) using isocratic flow (0.5 mL.min-1) of mobile phase acetonitrile (0.1% formic acid):0.002 M ammonium acetate in water as the mobile phase. The mass spectrometric detections were carried out in multiple reaction monitoring modes with precursor-to-product ion transitions with m/z 360.037 → 244.076 for CAP, m/z 581.431 → 365.047 LPB and m/z 494.526 → 394.141 for IS. The bioanalytical method validation studies were performed, ensuring regulatory compliance. Linearity (r2> 0.99) over analyte concentrations ranging from 5 and 40 ng.mL-1 was observed, while acceptable values were obtained for all other validation parameters. In a nutshell, a robust and green bioanalytical method was developed and applied for the simultaneous estimation of two anticancer agents from rat plasma.

Analytical method development, validation and forced degradation studies for rutin, quercetin, curcumin, and piperine by RP-UFLC method

SIGNIFICANCE

Curcumin, rutin, and quercetin are well-known flavonoids and piperine is an alkaloid, commonly used as spices and traditionally used to treat a variety of conditions. In the current scenario, the stability problems of phytoconstituents are a major problem for regulators and because of the complex nature of the components of plant extracts.

OBJECTIVE

A simple, fast, and sensitive ultra-force reverse phase liquid chromatography (RP-UFLC) has been developed, validated, and studied for degradation studies.

METHODS

Seven different plant extracts were quantified and the stability of the constituents was estimated by forced degradation studies. The separation of the phytoconstituents was performed on a Phenomenex C₁₈ column with a mobile phase of 80% acetonitrile and 20% (25 mM) ammonium acetate (pH 3) at a flow rate of 1 mL min^-1 detected at 380 nm.

RESULTS

The results of the study showed that the method developed was linear with a range of correlation coefficient 0.994-0.999. The specificity, precision, and accuracy were well within the limits. Quantification showed that a maximum content of curcumin (3.61%, w/w) was found in the extract of Curcuma longa L extract, piperine in Piper nigrum L (13.92%, w/w), rutin in Glycyrrhiza glabra L (15.19%, w/w), and quercetin in Camellia sinensis L (0.36%, w/w). Forced degradation studies have shown that rutin was very stable in acidic media (6.65%, w/w) and curcumin was less stable in alkaline media (100%, w/w).

CONCLUSION

The method developed was simple, fast, accurate, sensitive, and applicable for the determination of phytoconstituents in natural extracts and herbal formulations, individually or in combination and can be used as a quality control tool.

Systematic development of a bioanalytical UPLC-MS/MS method for estimation of risperidone and its active metabolite in long-acting microsphere formulation in rat plasma

A systematic approach to develop a UPLC-MS/MS method was applied for quantifying of risperidone (RISP), its active metabolite, 9-hydroxy risperidone (9-OH-RISP) and internal standard (propranolol) in rat plasma. Liquid-liquid extraction was performed using methyl tert-butyl ether for quantification of drug and its active metabolite by MS detection in the positive ion mode. Acquity UPLC system with BEH C18 (2.1 mm × 100 mm, particle size 1.7 μm) column was used along with acetonitrile (0.1% formic acid)-2 mM (milli mole) ammonium acetate in isocratic condition was used as the mobile phase. Detection was performed by multiple reactions monitoring with precursor-to-product ion transitions with m/z 411.2 → 191.0 for RISP, m/z 427.2 → 207.0 for 9-OH-RISP and m/z 260.1 → 116.0 for IS. The method was validated as per the FDA guidance on bioanalytical method validation. Linearity (r² = 0.999) was observed in the drug concentration ranging between 0.1 and 50 ng mL^-1, while all other parameters were found to be within the acceptable ranges. Method robustness was optimized by Box-Behnken design to monitor the influential variables to achieve maximal recovery of the analytes in the rat plasma. Pharmacokinetic evaluation of the analytes from long-acting microparticles in rat plasma showed two peaks indicating an initial burst effect within 24 h of administration followed by controlled drug release pattern upto 45 days, while marketed formulation (Risperdal Consta®) showed no plasma concentration during the lag-time of 21 days followed by maximal drug absorption between 28 and 40 days.

QbD-Driven Development and Validation of a Bioanalytical LC-MS Method for Quantification of Fluoxetine in Human Plasma

The current studies describe the Quality by Design (QbD)-based development and validation of a LC-MS-MS method for quantification of fluoxetine in human plasma using fluoxetine-D5 as an internal standard (IS). Solid-phase extraction was employed for sample preparation, and linearity was observed for drug concentrations ranging between 2 and 30 ng/mL. Systematic optimization of the method was carried out by employing Box-Behnken design with mobile phase flow rate (X1), pH (X2) and mobile phase composition (X3) as the method variables, followed by evaluating retention time (Rt) (Y1) and peak area (Y2) as the responses. The optimization studies revealed reduction in the variability associated with the method variables for improving the method robustness. Validation studies of the developed method revealed good linearity, accuracy, precision, selectivity and sensitivity of fluoxetine in human plasma. Stability studies performed in human plasma through freeze-thaw, bench-top, short-term and long-term cycles, and autosampler stability revealed lack of any change in the percent recovery of the drug. In a nutshell, the developed method demonstrated satisfactory results for analysis of fluoxetine in human plasma with plausible utility in pharmacokinetic and bioequivalence studies.