Transdermal sampling of vitamin D₃ and 25-hydroxyvitamin D₃

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Dermatology

Background:

• Blood analysis for vitamin D3 and its metabolites presents challenges.
• Transdermal analysis offers a non-invasive alternative for metabolite monitoring.

Purpose of the Study:

• To develop and validate a transdermal analysis method for vitamin D3 and its hydroxylated metabolite.
• To overcome limitations associated with traditional blood-based analytical techniques.

Main Methods:

• Direct extraction of vitamin D3 from skin using solid patches and liquid phases.
• Utilized deuterium-labeled vitamin D3 for accurate quantification of transdermal transfer rates.
• Evaluated various extraction solvents, identifying 50:50 octanol:isopropanol as optimal.

Main Results:

• Achieved an accuracy of 115% and reproducibility better than 30% with the optimized solvent system.
• Demonstrated successful transdermal analysis of vitamin D3 in porcine skin models.
• Microneedle-assisted extraction yielded accurate measurements within 1 hour.

Conclusions:

• Transdermal analysis is a viable method for vitamin D3 quantification in skin.
• Microneedles significantly enhance the speed and accuracy of transdermal vitamin D3 analysis.
• Extraction duration impacts accuracy, with 2 hours optimal for intact skin.