Pharmacokinetic Comparison of Lutein and Zeaxanthin in Granule, Beadlet, and Liposomal Powder Formulations Following Single OralAdministration in Male Sprague-Dawley Rats

Introduction: Lutein and zeaxanthin are xanthophyll carotenoids critical for maintaining retinal health and preventing age-related macular degeneration. However, their clinical utility is limited by poor aqueous solubility and low bioavailability. Lipid-based formulations may enhance systemic absorption, thereby improving therapeutic potential. This study compared the pharmacokinetic profiles of three oral Lutein-Zeaxanthin (LZ) formulations in rats. Methods: Eighteen male Sprague-Dawley rats (n = 6/group) were randomized to receive a single oral dose of LZ equivalent to 10 mg/kg lutein in one of three formats: granules (G1), beadlets (G2), or liposomal powder (G3). Plasma samples were collected at predetermined intervals up to 24 h post-dose and analyzed using LC-MS/MS. Pharmacokinetic parameters, including Cmax and AUC0?ℵ, were calculated using Phoenix WinNonlin® and compared via ANOVA with Dunnett's post-hoc test. Results: Mean lutein Cmax values were 51.59 ng/mL (G1), 52.80 ng/mL (G2), and 62.39 ng/mL (G3). Corresponding AUC0?ℵ values were 472.9, 504.6, and 536.7 ng·h/mL, respectively. G3 demonstrated statistically significant improvements in both Cmax and AUC0?ℵ compared with G1 and G2 (p < 0.0001). Discussions: The enhanced systemic exposure observed with G3 likely reflects improved dispersibility and micellar incorporation of lutein in the lipid matrix, facilitating intestinal absorption. These findings align with previous reports on the enhancement of lipid-based bioavailability for lipophilic nutrients. Conclusion: Liposomal powder formulations significantly enhance lutein absorption compared to granules and beadlets, supporting their use in advanced nutraceutical formulations for ocular health.