The native fluorescence characteristics of metoclopramide in various solvents and at different pH values were determined qualitatively and quantitatively. Fluorimetric determinations can be performed directly and are based on an intense emission at 360 nm that occurs when the sample is excited at 310 nm following dilution in pH 2.0 buffer solution to a final concentration up to 6 µg ml^–1. The detection limit is 3 × 10^–2µg ml^–1.

A comparison is made between the fluorescence behaviour of metoclopramide and the structurally analogous procainamide molecule. Finally, metoclopramide has been converted into its monoacetyl derivative at the primary aromatic amine function. Spectral data confirming the structure are reported. Apart from the second-order excitation shoulder at 275 nm, no significant difference concerning fluorescence behaviour, qualitative or quantitative, between the acetyl derivative and the original molecule is established.