A RAPID, SIMPLE AND SENSITIVE SPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF NO FROM NO DONORS

Aim. To develop and validate a spectrophotometric UV-VIS method for the determination of nitric oxide (NO) released from NO donors, such as nitric oxide-releasing nonsteroidal anti-inflammatory drugs (NO-NSAIDs), with poor solubility in aqueous medium. Material and methods: The method is based on the nitric oxide-mediated stress (nitrosative stress) through sulfanilamide that reacts with N-(1-naphthyl)ethylenediamine dihydrochloride to form a pink-red azo dye with maximum peak at 540nm. The method was validated in term of linearity, detection limit, quantification limit, precision, and accuracy. Results: The linearity of the method was proved for range of 0.78-100μM NaNO2 with a correlation coefficient of 0.9998. The accuracy of the method was checked by recovery experiment performed at three concentrations, i.e., 20 μM, 40 μM and 60μM NaNO2 and the recovery (%) was found to be in the range of 98.34% and 101.96%. The low values of relative standard deviation (RSD) are indicative of the accuracy and reproducibility of the method. The precision of the method was studied as intraday and interday variations. An RSD less than 2% indicates that the method is precise. Conclusions: This research offers all the proofs that recommend the use of this method for the determination of NO released from NO donors, such as NO-NSAID, using a hydroalcoholic medium, as it has good sensitivity, precision, and accuracy.