Used as a chromogenic substrate in enzymatic assays, particularly for studying protease activity. The compound releases p-nitroaniline upon cleavage by specific enzymes, producing a yellow color that can be measured spectrophotometrically. This allows for real-time monitoring of enzyme kinetics and inhibition. Commonly employed in research settings to evaluate serine proteases and other hydrolases. Its high sensitivity and clear signal output make it suitable for both manual and automated assay systems.