Micellar‐Enhanced Native Fluorescence Spectrofluorimetric Method for Determination of Cyclic Adenosine Monophosphate in Human Nasal Secretions

Cyclic adenosine monophosphate (cAMP) is required for turning chemical signals into electrical impulses in the olfactory system, and low levels in people with olfactory deficits result in olfactory dysfunction. A micellar-based spectrofluorimetric approach has been developed to quantify cAMP in human nasal secretions, offering an efficient tool for assessing cAMP. The proposed method is based on enhancing the native fluorescence intensity of cAMP by leveraging an optimized micellar system, where hydrogen bonds form between cAMP's hydroxyl and amine groups and the sulfate groups of sodium dodecyl sulfate, resulting in a significant rise in fluorescence emission at 342 nm upon excitation at 255 nm. The method was validated and demonstrated sensitive linearity and precision within the concentration range of 10-200 ng/mL, with a lower limit of quantification at 1 ng/mL. The method was used to compare cAMP levels in the nasal secretions of healthy people and patients with olfactory dysfunction, revealing significantly lower cAMP concentrations in the latter group. This finding highlights the significant role of cAMP in the olfactory process and how dysregulation contributes to olfactory dysfunctions. Because of its simplicity, sensitivity, and selectivity, the technique can be used in clinical research diagnostic applications to explore olfactory disorders.