Technical Note: A method for determination of titanium dioxide concentration in fecal samples.

Area of Science:

• Animal Science
• Analytical Chemistry

Background:

• Titanium dioxide (TiO2) is a common marker for indirect diet digestibility assessment in animals.
• Measuring TiO2 concentrations in fecal samples can be challenging with existing methods.

Purpose of the Study:

• To develop and validate an accurate and precise method for quantifying titanium dioxide in equine fecal samples.

Main Methods:

• The method involves dry-ashing fecal samples, followed by digestion with ammonium sulfate in concentrated sulfuric acid.
• Hydrogen peroxide is added to induce a color change, allowing for spectrophotometric analysis.
• Accuracy was assessed via spike recovery, and precision by calculating the coefficient of variation (CV) between sample duplicates.

Main Results:

• Spike recovery for TiO2 averaged 106%, indicating high accuracy.
• The CV between duplicate samples averaged 4.0%, with 79% of pairs showing a CV below 5%, demonstrating excellent precision.
• The developed method exhibited significantly lower CVs compared to a previously published method (P < 0.0001).

Conclusions:

• The new spectrophotometric method provides a reliable and reproducible analytical procedure for TiO2 determination in equine feces.
• This method enhances the ability to accurately assess diet digestibility in horses using titanium dioxide as a marker.