Fabrication and evaluation of a plasmonic biosensor based on silica-coated gold nanorods for highly-sensitive detection of anti-Müllerian hormone

Anti-müllerian hormone is a crucial biomarker for reproductive potential, but current detection methods are not cost-effective or time-efficient. In this study, we set out to develop a biosensor using gold nanorods (Au-NRs) coated with a functionalized silica network. The biosensor structure was completed by covalently binding the anti-Müllerian hormone antibody to SiO₂@Au-NRs. We confirmed the proper coating of the gold nanorods using HR-TEM, EDS/EDAX, zeta potential, and FT-IR analysis. To assess the sensitivity of SiO₂@Au-NRs, we analyzed the LSPR peak position redshift in different concentrations of ethylene glycol. The biosensor was then used to recognize the AMH antigen and determine the limit of detection (LoD) and quantification (LoQ) for the biosensor. Our research has shown that the SiO₂@Au-NRs have a suitable thickness. The SiO₂@Au-NRs demonstrated impressive sensitivity as a nano biosensor. The AMH antigen identification results indicated that the nano biosensor was highly sensitive. The LoD and LoQ values were 0.086 and 0.262 ng ml⁻¹, respectively, very close to the values obtained by the ELISA kit. Furthermore, LSPR biosensors have reduced detection costs and measurement time. Their high sensitivity makes them excellent candidates for use in diagnostic kits.