Determination of mangiferin in rat eyes and pharmacokinetic study in plasma after oral administration of mangiferin-hydroxypropyl-beta-cyclodextrin inclusion

Abstract

Purpose: To determine whether mangiferin can enter the eye, because the eye possesses the unique blood-ocular barrier.

Methods: Due to the low solubility of mangiferin, hydroxypropyl-beta-cyclodextrin was applied to improve the absorbance. A reversed-phase high-performance liquid chromatography assay for mangiferin in rat plasma and eye fluid was developed. The mobile phase consisted of methanol-0.6% glacial acetic acid (27:73, v/v) at a flow rate of 1.0 mL/min.

Results: Peak areas of mangiferin were linear over a concentration range of 0.40-20.00 microg/mL in blood samples and a range of 0.10-5.00 microg/mL in eye samples, respectively. Intra- and interassay precision and accuracy of mangiferin fell well within the predefined limits of acceptability (<15%). The recovery was 81.12%-87.18% in the plasma and 79.96%-85.52% in the eye, respectively. The analytical method had excellent sensitivity using a small sample volume (20 microL) with the lower limit of quantification, 0.4 and 0.10 microg/mL for plasma and eye, respectively. Pharmacokinetic parameters of mangiferin in plasma were obtained as follows: T(max) = 7 h, C(max) = (4.43 +/- 0.62)microg/mL. The time point of 7 h was chosen for eye sample detection, as it had maximum plasma concentration. The concentration of mangiferin in the eye tissue 7 h after oral administration was (0.34 +/- 0.13)microg/mL (n = 6), coefficient of variation % = 38.24%.

Conclusions: Mangiferin can pass the blood-ocular barrier and is suitable to be used as an antioxidant in eye diseases.