Quetiapine Fumarate: A Review of Analytical Methods

Atypical antipsychotics are newer second-generation antipsychotics with weak dopamine type 2 blocking but potent 5-HT2 antagonistic activity. They are considered first-line treatments for schizophrenia and gradually replace typical antipsychotics. Extrapyramidal side effects are minimal, and they tend to improve impaired cognitive function in psychotics. Quetiapine fumarate is an atypical antipsychotic drug used to treat schizophrenia, mania and depression in people with bipolar disorder combined with other drugs or alone. Quetiapine was developed in 1985 and approved for medical use in the USA in 1997. Thorough computer-aided literature, surveys revealed that numerous analytical methods were reported over the years. The present study reviews analytical methods with their validation parameters published during the last 22 years (1999-2021) either as a single entity or combination in dosage form, and determination from biological samples. Novel strategies for increasing separation quality, such as QbD analysis and green spectroscopy, were discovered during the evaluation, and this review can be utilized for further research reference.

Trace-level determination of potential genotoxic impurities in quetiapine fumarate using LC-MS

A novel LC-MS method was developed and validated to determine three potential genotoxic impurities, namely 2-(2-aminophenylthio)benzoic acid hydrochloride, 2-aminothiophenol, and 2-(2-aminophenylthio)benzonitrile, at trace level (~1.6 ppm) in quetiapine fumarate drug substance, an antipsychotic drug. These impurities are potentially genotoxic and therefore should be controlled at or below specific acceptance limits. An InertSustain AQ-C18 column (250 × 4.6 mm, 5 μm) in reversed-phase mode with the column temperature at 45°C was used. The mobile phase was 0.1% trifluoroacetic acid in water and acetonitrile with gradient elution mode, and the run time was 45 min. The flow rate was 0.8 ml/min. A mass spectrometer was used to quantify the amount of impurities using electrospray ionization mode at specific m/z 245.9, 126.0, and 226.9 for 2-(2-aminophenylthio)benzoic acid hydrochloride, 2-aminothiophenol, and 2-(2-aminophenylthio) benzonitrile, respectively. The method was found to be sensitive and possessed excellent linearity in the concentration ranges from the limit of quantification to 150% of the permitted level (0.47-2.36 μg/ml) with correlation coefficients above 0.999. The results showed that the method was specific, precise, linear, and accurate for the estimation of these three impurities in quetiapine fumarate.