Given that mpGNS-3 exhibits optimal morphology for maximum color brightness, we next evaluated its colorimetric detection sensitivity across RVFV nucleoprotein concentrations and compared its performance with that of traditional GNP-based LFIA. To quantify the detection performance, the calibration curve was constructed by plotting the average grayscale values of the test line against the RVFV concentrations. Figure presents the colorimetric visualization of LFIA strips for GNP at RVFV nucleoprotein concentrations ranging from 500 ng/mL to 1 ng/mL. The corresponding gray value intensity profiles are shown in Figure . Figure presents the calibration curve, which correlates the gray value intensity of the test lines with the logarithm of RVFV protein concentration. Two distinct linear regions were identified: one ranging from 500 ng/mL to 200 ng/mL and the other from 200 ng/mL to 10 ng/mL. The limit of detection (LOD) was determined using the International Union of Pure and Applied Chemistry (IUPAC) definition: LOD = 3σ/S, where σ is the standard deviation of blank measurements and S is the slope of the linear equation in the low concentration range (200 ng/mL to 10 ng/mL). The calculated LOD for GNP was as low as 2 ng/mL. For mpGNS-3, the LFIA strip images exhibit clear visual detection at nanogram-level RVFV concentrations, with the test line remaining visible even at a concentration of 5 pg/mL. This result highlights its superior colorimetric detection capability compared to GNP. Figure displays the colorimetric visualization of LFIA strips for mpGNS-3 at RVFV nucleoprotein concentrations ranging from 2.5 ng/mL to 1 pg/mL, with the corresponding gray value intensity profiles shown in Figure . The analytical calibration curve for mpGNS-3, illustrated in Figure , was generated by plotting the averaged grayscale values of the test line against the logarithm of RVFV nucleoprotein concentrations. Two distinct linear regions were identified: one spanning 2.5 ng/mL to 100 pg/mL and another covering 100 pg/mL to 5 pg/mL.