A graphene oxide assisted surface plasmon resonance sensor for chloroquine phosphate detection: A theoretical and experimental study

Abstract

The present work deals with a surface plasmon resonance (SPR) sensor that gives real-time and label-free detection of chloroquine phosphate (CQ) with graphene oxide (GO) in water as well as real samples. In this work, theoretical and experimental analysis are performed for present SPR biosensor for the detection of CQ. Furthermore, a self-assembled monolayer (SAM) of 4-aminothiophenol (4-ATP) is utilized for the attachment of GO over the gold layer, which works as a good probe for the detection of CQ. The present biosensor detects micromolar concentrations of CQ in water and real samples (blood serum) with a limit of detection (LOD) value of 0.21 μM and 0.34 μM, respectively. Furthermore, other biomolecules like urea, L-cysteine, D-glucose and glycine are also tested and it shows maximum sensitivity towards CQ. © 2025 Elsevier Ltd