<p> A sensing platform has been developed based on the synergistic combination of gold-platinum nanoparticles (Au-PtNPs) with hydroxylated multiwalled carbon nanotubes (MWCNT-OH) as a conductive material for the sensitive detection of carbaryl in agricultural products. The nanocomposite, consisting of Au-PtNPs/MWCNT-OH, was deposited on a glassy carbon electrode (GCE) via simple drop-casting and further investigated for its electrochemical performance as a sensing platform for detecting carbaryl. Additionally, different instrumentation techniques, including Raman and Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy-energy dispersive spectroscopy (FESEM-EDS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), were employed to characterise the surface morphology and structural properties of the Au-PtNPs/MWCNT-OH nanocomposite. Based on the electrochemical investigation, the proposed electrode, Au-PtNPs/MWCNT-OH-modified glassy carbon electrode, exhibited a broad linear range for carbaryl (0.4–600 µM), a low limit of detection (0.11 µM), and good stability and reproducibility (RSD &lt; 5%). Moreover, the proposed electrode has been investigated for its selectivity in the presence of 11 different interfering species (paraoxon-ethyl, diazinon, acephate, thiamine, ascorbic acid, glucose, urea, MgSO₄, FeSO₄, Zn(NO₃)₂, and NaNO₃), demonstrating satisfactory selectivity. Further examination of this proposed electrode to determine carbaryl concentration in two different samples (rice and corn) yielded results with acceptable recovery, suggesting the potential for further development as a novel point-of-care platform for the rapid detection of pesticide residues in agricultural samples.</p> Graphical abstract <p></p>