Determination of Crizotinib in Mouse Tissues by LC-MS/MS and Its Application to a Tissue Distribution Study

Crizotinib: A comprehensive profile

Crizotinib, approved in 2011, was the first approved inhibitor targeting anaplastic lymphoma kinase (ALK) It used for treatment of the patients with metastatic non-small cell lung cancer (NSCLC) that is anaplastic lymphoma kinase (ALK) positive. This chapter provides a complete review of crizotinib including nomenclature, physiochemical properties, methods of preparation, identification techniques and various qualitative and quantitative analytical techniques as well as pharmacology of crizotinib. In addition, the chapter also includes review of several methods for separation of crizotinib using chromatographic techniques.

Innovative use of σ and π electron acceptors in the development of three high throughput 96-microwell spectrophotometric assays for crizotinib

Crizotinib (CZT) is a potent and selective tyrosine kinase inhibitor used for treatment of non-small cell lung cancer (NSCLC). The development of high-throughput assays for its quality control (QC) is very essential to assure its therapeutic benefits. CZT molecule has multiple electron-donating atoms that can contribute to the formation of colored charge-transfer (CT) complex with iodine as σ-electron acceptor and with 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (CHBQ) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) as π-electron acceptors. These reactions were prospective basis for development of three innovative 96-microwell-based spectrophotometric assays for CZT. The reactions of CZT with iodine, CHBQ and TCNQ were performed in 96-microwell assay plates and absorbances of the CT complexes were measured by microwell absorbance reader at their corresponding maximum absorption peaks. The measured absorbances were correlated with the CZT concentrations in its sample solutions. Beer's law was obeyed with excellent correlation coefficients in the range of 0.5-30, 2-500, and 5-500 µg mL^-1 for assays using iodine, CHBQ and TCNQ, respectively. The limits of detection were 2.17, 0.85 and 6.23 µg mL^-1 for assays using iodine, CHBQ and TCNQ, respectively. The validation studies confirmed the accuracy and precision of all the proposed assays. The assays were successfully applied in the determination of CZT in Xalkori capsules. The proposed assays have very simple procedures to run in QC laboratories. Also, both assays enable analyst to process large number of samples and use of very small volumes of the organic solvent (ecofriendly and inexpensive).