Insight into amino acids-stabilized silver nanoparticles as a probe for quantification of methionine

• Published in: Journal of molecular liquids 2024-03, Vol.398, p.124272, Article 124272
• Main Authors: Sadeeq, Hadeel A., Awad, M.I., Kassem, Mohammed A.
• Format: Article
• Language: English
• Subjects: Aggregation mechanism; AgNPs; Methionine; Pharmaceutical; Surface Plasmon resonance
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2024.124272

[Display omitted] •Two new methods were developed for micro-determination of methionine (MET).•The developed methods were based on amino acids stabilized-silver nanoparticles (AgNPs).•The binding between MET and stabilized-AgNPs was investigated.•All optimal conditions for the binding were inspected.•MET were successfully determined in some real samples. Two novel, simple and fast methods were developed for spectrophotometric micro-determination of methionine (MET, the analyte) using amino acids stabilized-silver nanoparticles (AgNPs). These methods were based on controlled preparation of AgNPs using NaBH4 as reducing agent, and subsequently stabilized using two different amino acids, i.e., alanine for sol 23 and leucine for sol 26. The thus stabilized-AgNPs and their binding with MET were confirmed and investigated using different tools as UV/Vis spectrum, TEM, FT-IR and cyclic voltammetry. All experimental conditions such as the effects of pH, time, temperature and the ionic strength were investigated and optimized. After that, a calibration curves were constructed based on the decrease in the surface Plasmon resonance, (SPR) peak with a characteristic pale yellow color, at about 390 nm after MET addition to sol 23 and sol 26 due to the binding between MET and stabilized-AgNPs and in turn color changed to a pale gray. The dynamic range for MET quantification was 1.5–15.0 µg/mL for both sols with good correlation coefficients and high precision. With respectable recovery percentages, the established procedures were successfully used to determine MET in pharmaceutical capsules and in some spiked human blood samples.