High-sensitive surface plasmon resonance sensor for melamine detection in dairy products based on graphene oxide /chitosan nanocomposite

Abstract

Accurate diagnosis and determination of the appropriate dose of melamine is crucial, especially in children's food, due to the potential for severe side effects such as kidney stones. This research has demonstrated the effectiveness of the graphene oxide-chitosan (GOCS) composite in modifying the gold chip surface as a sensor platform, resulting in a significant 1.17° angular change relative to the bare gold chip for the detection of melamine. The GOCS composite was analyzed using SEM, XRD, and FTIR. The GOCS sensor exhibited high sensitivity with a value of 239.1^◦μM⁻¹, a linear range (L.R) of 0.01–200 μM, affinity constant of 1.73 × 10⁴ and an impressive limit of detection (LOD) of 10 nM. These findings highlight the potential of the GOCS sensor for accurately and precisely detecting melamine. Additionally, we compared the obtained results from the sensor with those from the standard method of HPLC, which is referred to as the gold standard in analytical chemistry, by conducting tests using GOCS/Au to identify melamine in commercial samples. The comparison showed that the GOCS sensor offers desirable features for analyzing real samples, making it a promising tool for accurately and efficiently detecting melamine in various samples.