Stability-indicating liquid chromatographic method for the quantification of the new antipsychotic agent asenapine in bulk and in pharmaceutical formulation

Two New HPLC Methods, Assessed by GAPI, for Simultaneous Determination of Four Antipsychotics in Pharmaceutical Formulations: A Comparative Study

Antipsychotics are widely used to treat various mental disorders. Combination therapies were approved by the FDA to treat manic states. Quetiapine fumarate, aripiprazole, asenapine maleate, and chlorpromazine HCl are frequently used for treatment of these disorders. Green analytical chemistry is primarily concerned with reducing waste generated during sample preparation or analysis. Green solvents, such as ethanol, are being used in HPLC as an alternative to acetonitrile. To this purpose, two new chromatographic methods were developed to determine these four drugs simultaneously in their bulk and pharmaceutical formulations. The greenness of both methods was assessed by the green analytical procedure index (GAPI)—one of them was found to be green ecofriendly, and the other had some environmental hazards (conventional)—and this helps laboratories to choose a method that suits their capabilities. The chromatographic separation for both methods was carried out on a Thermo® C18 column. The total separation times were about 11 min and 9 min for the green and the conventional methods, respectively. Using the Student’s t-test and the F-ratio, there was no significant difference between the results of the two methods. These methods have been validated and successfully applied to the analysis of commercial pharmaceutical formulations. Our study could successfully be used in central quality control laboratories, which need a single analytical method to separate more than one compound with similar pharmacological action.

Determination of Asenapine Maleate in Pharmaceutical and Biological Matrices: A Critical Review of Analytical Techniques over the Past Decade

Asenapine maleate is a second-generation atypical antipsychotic agent used in the treatment of schizophrenia, a neuropsychiatric disorder. It is available as a fast-dissolving sublingual tablet to avoid extensive first-pass metabolism with higher bioavailability as compared to oral formulations. Although, the established therapeutic solutions do not sufficiently satisfy the patient's safety and efficacy needs. Thus, the core research emphasis is to investigate strategies to produce novel formulations with enhanced safety and efficacy. This necessitates the development of robust, precise, and accurate methods for quantification of asenapine maleate in different sample matrices. Given the foregoing information, the current analysis concentrates on the different analytical techniques used to assess asenapine maleate in bulk, pharmaceutical formulations, and biological specimens. Reverse-phase HPLC coupled with UV detection is a majorly (nearly 50% of papers investigated) used technique for the estimation of asenapine maleate in formulations. On the other hand, for its quantification in the biological matrix, hyphenated techniques using mass spectrometry are widely used. This critical review reveals different analytical methodologies, including spectrophotometric, chromatographic, capillary electrophoresis techniques reported from 2011 to 2020, for the measurement of asenapine maleate in various sample matrices. The information presented in this review would be useful in future research for robust analytical method development for asenapine maleate utilizing a more scientific and risk-based approach. Also, it would aid to minimize analytical failure as well as method fine-tuning throughout the product life cycle. Further, this review may also direct scientists toward the development of methodologies for green research.

Validation of an RP-HPLC Method for the Determination of Asenapine Maleate in Dissolution Media and Application to Study In Vitro Release from Co-Crystals

Asenapine maleate is an antipsychotic drug that is indicated in the treatment of schizophrenia and bipolar disorders. It has low aqueous solubility and high permeability (Class II drug) and undergoes an extensive first pass effect. These problems result in low oral bioavailability (<2%). To enhance its solubility/dissolution rate and hence bioavailability, co-crystals using different co-formers in different ratios were prepared and evaluated. To study the in vitro dissolution of the drug from these co-crystals into phosphate buffer (pH 6.8), an RP-HPLC method was developed and validated according to the ICH Q2R1 guidelines. The method was linear in the range 0.1–14 µg/mL (R > 0.9998) and accurate and precise. An ANOVA test indicated that calibration curves run on different days did not differ significantly. It was sensitive (lower limit of quantitation (LLOQ) = 25.03 ng/mL), specific (the co-formers did not interfere with the determination of the drug), and robust to small changes in the mobile phase (pH, composition, and flow rate). The in vitro release of asenapine maleate from the co-crystals and the physical mixture was much enhanced when compared to the in vitro dissolution of the unprocessed drug. In conclusion, the developed and validated RP-HPLC method met the acceptance criteria and was applied successfully in evaluating the in vitro release of the drug.

One-pot reaction for determination of Asenapine maleate through facile complex formation with xanthine based dye: Application to content uniformity test

Asenapine maleate was approved by the FDA for the treatment of schizophrenia and mania or mixed episodes with bipolar I disorder. In the present article, two spectroscopic methods were developed and validated for the determination of asenapine. Both methods depend on association complex formation between xanthine based dye (eosin Y) and the cited drug in acetate buffer pH = 3.8. In the spectrophotometric method (method I), the absorbance of the formed complex was estimated at maximum wavelength of 545 nm and Beer's law was obeyed in the range of 1-12 μg mL^-1. The spectrofluorimetric method (method II) depends on measuring the quenching effect of the drug on the native fluorescence of eosin Y at 545 nm after excitation at 303 nm. The linearity range of method II was 0.4-3.2 μg mL^-1. The limits of detection were 0.24 and 0.08 μg mL^-1 for method I and II, respectively. The instructions of ICH were followed to fully validate the developed analytical procedures. The formation constant of the reaction was 3.93 × 10⁴ while its Gibb's free energy was -2.6 × 10⁴ J mol^-1. Finally, the methods were applied for the analysis of pharmaceutical tablets and for evaluation of their content uniformity.

Photolytic and photocatalytic transformation of an antipsychotic drug asenapine: Comparison of kinetics, identification of transformation products, and in silico estimation of their properties

The photolytic and photocatalytic transformation of an antipsychotic drug asenapine with the use of H₂O₂ and TiO₂ was studied. A method employing irradiation with a simulated full solar spectrum in the photostability chamber was applied, then the reverse-phase ultra high performance liquid chromatography with diode array detector, coupled with electrospray quadrupole time-of-flight mass spectrometer (RP-UHPLC-DAD - ESI-Q-TOF) was used for the quantitative and qualitative analysis of the processes. The developed quantitative method was fully validated, according to the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) guidelines, and the kinetic parameters of asenapine photodecomposition were compared. Nineteen phototransformation products were detected, and their probable structures - mainly hydroxylated and oxidized asenapine derivatives - were suggested. On the basis of the elucidated structures the computational prediction of their toxicity at the various endpoints, as well as bioconcentration factors and biodegradability was performed. The obtained results were then subjected to the principal component analysis (PCA). This chemometric technique facilitated comparison of the applied models, calculated properties of the TPs, and enabled visualization of relationships between them.

Studies on photodegradation process of psychotropic drugs: a review

Consumption of psychotropic drugs is still increasing, especially in high-income countries. One of the most crucial consequences of this fact is significant release of them to the environment. Considerable amounts of atypical antipsychotics, benzodiazepines, antidepressants, and their metabolites were detected in river, lake, and sea water, as well as in tissues of aquatic organisms. Their ecotoxicity was proved by numerous studies. It should be noticed that interaction between psychotropic pharmaceuticals and radiation may lead to formation of potentially more toxic intermediates. On the other hand, photo-assisted wastewater treatment methods can be used as an efficient way to eliminate them from the environment. Many methods based on photolysis and photocatalysis were proposed and developed recently; nevertheless, the problem is still unsolved. However, according to recent studies, photocatalysis could be considered as the most promising and far more effective than regular photolysis. An overview on photolytic as well as homogenous and heterogeneous photocatalytic degradation methods with the use of various catalysts is presented. The photostability and phototoxicity of pharmaceuticals were also discussed. Various analytical methods were used for the photodegradation research, and this issue was also compared and summarized. Use of high-resolution multistage mass spectrometry (Q-TOF, ion trap, Orbitrap) was suggested. The combined techniques such as LC-MS, GC-MS, and LC-NMR, which enable qualitative and quantitative analyses in one run, proved to be the most valuable in this case. Assembling of MS/MS spectra libraries of drug molecules and their phototransformation products was identified as the future challenge.