Optimization and Evaluation of the Accuracy of the C-Reactive Protein Detection Range in a Rapid Test Based on Lateral Flow Immunoassay with Two Clinical Cut-Offs

Rukmi, Ai
Darmawati, Sri
Alisjahbana, Bachti
Depamede, Sulaiman Ngongu
Pambudi, Sabar
Yuwita, Anita

BIOEDUSCIENCE
Vol 10 No 2 (2026): BIOEDUSCIENCE

Background: C-Reactive Protein (CRP) is an important biomarker for infection and inflammation; however, quantitative assessment using ECLIA is costly and requires adequate laboratory facilities and trained personnel. This study aims to optimize antibody concentration and conjugate volume, and to evaluate the accuracy of the detection range of an LFIA-based CRP rapid test at two clinical cut-offs (10 and 40 mg/L). Methods: Experimental research was conducted by optimizing antibody concentrations on the T1 and T2 lines, optimizing CGC volume, and testing sensitivity, specificity, and the correlation between color intensity and Image. Results: The optimal antibody concentrations were obtained at T1 of 0.075 mg/mL and T2 of 0.025 mg/mL with a CGC volume of 2 µL. Sensitivity and specificity were 95.7% and 100% at T1, and 83.3% and 95.5% at T2. Conclusions: The developed CRP rapid test has adequate diagnostic performance as a semi-quantitative screening tool in primary healthcare facilities.