RESUMEN
High-performance liquid (HPLC) and thin-layer (TLC) chromatographic methods for the detection and quantification of diazeniumdiolates are described. The HPLC determinations were made using a Rocket Platinum NH2 column (7 x 53 mm, 100-A pore size, 3-microm particle size), under isocratic conditions with mixtures of acetonitrile, methanol, and water containing 0.1% diethylamine (v/v), at a flow rate of 2.5 ml/min, a column temperature of 22 degrees C, and UV detection at 250 nm. The TLC determinations were similarly made using Merck NH2 F254S precoated glass plates (approximately 2 x 5 cm, 5-microm particle size, 0.2-mm layer thickness) with mixtures of acetonitrile, methanol, and water containing 0.1% diethylamine (v/v). Preexisting traces of carcinogenic nitrosamines were detected in some samples of diazeniumdiolates. The methods provide a more efficient means of characterizing the purity of diazeniumdiolate samples prepared for use in biomedical applications than older procedures which rely on differential absorbance measurements at 250 and 350 nm, respectively.