Related Experiment Video
Updated: Sep 28, 2025

Author Spotlight: Investigating Physiological Functions of Vitamin A Transporters Using HPLC-Based Vitamin A Profiling
Published on: December 27, 2024
Study of vitamin D penetration in the human aqueous after topical administration
Massimo Lorusso1, Luisa Micelli Ferrari2, Maria Vittoria Cicinelli3
1161123Ente Ecclesiastico Ospedale Generale Regionale Francesco Miulli, Strada Provinciale Acquaviva-Santeramo Km 4100, 70021.
Purpose:
this study was designed to measure the concentration of Vitamin D in the aqueous and to investigate if its topical application can increase quantities in aqueous humor.
Methods:
29 patients scheduled for cataract surgery were divided into two groups. Group 1 was used as a control group, in group 2 patients were instructed to instill one drop of vitamin D eye drops three times daily 10 days before surgery .Aqueous humor was collected with a 30-gauge needle immediately before surgery. Vitamin D concentrations were analyzed by liquid chromatography tandem mass spectrometry.
Results:
Aqueous humor (AH) samples in both groups had small but detectable vitamin D levels. In the AH concentrations of vitamin D were, respectively, 2.1ng/mL 0.4 in group 1 and 2.1ng/mL0.3 in group 2(P = 0.9).
Conclusion:
Our study confirmed the presence of vitamin D in AH. No significant difference of vitamin D concentration in AH was observed between the treatment and control group.
Related Concept Videos
Role of Skin in Vitamin D Synthesis
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin...
Volume of Distribution
Methods for Studying Drug Absorption: In situ
The Doluisio method involves perfusing a prepared segment of a rat's small intestine with a solution of radiolabeled drug and a non-absorbable marker. This helps to differentiate between absorbed and non-absorbed drug concentrations. The intestinal segment is connected at both ends using tubing and syringes,...
Methods for Studying Drug Absorption: In vitro
The diffusion cell method uses a two-compartment cell, including a donor compartment with the drug solution, which simulates the environment where the drug is applied, and a receptor compartment with a buffer solution, which simulates the environment...

