Used as a reference standard in analytical laboratories to quantify indole-3-acetic acid (IAA) levels in plant tissues, environmental samples, and biological fluids. Commonly employed in high-performance liquid chromatography (HPLC) and mass spectrometry (MS) methods to ensure accurate detection and calibration. Essential for research on plant hormone regulation, growth studies, and quality control in agricultural and botanical testing. Helps maintain consistency and reliability in experiments involving auxin metabolism and plant development.