Jingjing, Yang, Zhen, Liang, Ping, Lu, Fei, Song, Zhen, Zhang, Huiyun, Xia, Jijun, He, Tianyang, Zhou, and Junjie, Zhang
Luliconazole (LCZ) is a novel antifungal imidazole with broad-spectrum and high susceptibility of Aspergillus and Fusarium are the dominant species of fungal keratitis, may potentially be a new medical treatment option for ocular fungal infection. To evaluate LCZ distribution in ocular tissues after topical application for the development of ophthalmic delivery system, it is important to have a bioanalytical method for measuring the drug concentrations in different ocular tissues and aqueous humor (AH). A selective and sensitive ultrahigh performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) method was developed for the quantification of LCZ in rabbit ocular tissues, including conjunctiva, cornea, AH, iris, lens, vitreous humor (VH), retinal choroid and sclera, using lanoconazole as internal standard (IS). Chromatographic separation was achieved on a Xterra MS, C18 column (2.1 × 50 mm, 3.5 μm) using mobile phase with formic acid solution (0.2%, v/v): acetonitrile (50:50, v/v) at a flow rate of 0.2 ml/min, and the run time was 2.5 min. Detection was performed using the transitions 354.1 → 150.3 m/z for LCZ and 320.1 → 150.3 m/z for IS by positive ion electrospray ionization in multiple reaction monitoring (MRM) mode. Method validation was conducted in accordance with U.S. Food and Drug Administration's regulatory guidelines for bioanalytical method validation. The calibration curves were linear over the concentration range from 2.80 ng/ml to 2038 ng/ml for conjunctiva, cornea and sclera, 2.09 ng/ml to 1019 ng/ml for AH, 2.09 ng/ml to 509.5 ng/ml for iris, 2.09 ng/ml to 203.8 ng/ml for retinal choroid and VH, 2.04 ng/ml to 101.9 ng/ml for lens, with all the squared correlation coefficients (r