Electrochemical sensing of the maple syrup urine disease biomarker valine, using saffron-silver nanoparticles

Abstract

Metabolic disorders are inherited disorders in which genetic defects prevent a metabolic pathway and cause enzymes to malfunction. Maple syrup urine disease (MSUD) is a rare metabolic disease marked by high levels of branched-chain amino acids (b-AAs), leucine, isoleucine, and valine. Elevated concentrations of b-AAs pose issues including liver failure, neurocognitive impairment, and mortality. Given the unavoidable repercussions for newborns, it is critical to establish quick and adaptable diagnoses in the early stages of life. Thus, this study highlights the development of a novel electrochemical sensor for valine detection (MSDU biomarker) based on a modified carbon paste electrode (CPE) with electropolymerized silver nanoparticles capped with saffron (AgNPs@Sa) synthesized using a green method. Thus, a modified carbon paste electrode (CPE) with a conductive polymer posing silver nanoparticles was employed to sensitively determine Val in this paper. Saffron capped with silver nanoparticles (AgNPs@Sa) were synthesized, using a green method and studied using cyclic and square wave voltammetry. Cyclic voltammetry (CV) was used in the electropolymerization of AgNPs@Sa on CPE (poly-AgNPs@Sa-CPE) and utilized in the detection of Val. The modified electrode under the selected conditions produced square wave signals with valine mass concentrations ranging from 0.258 to 11.94 ng L−1 in the case of buffer solutions and it was successfully applied in urine samples. The assay proved to be simple, rapid, and cost-effective, sensitive with a low detection limit of 0.085 and 0.097 ng L−1 for buffer and urine samples, respectively.