From bioinformatics to clinical application: A new strategy in CRP detection with peptide aptamer

C-Reactive protein (CRP) is a key biomarker for evaluating inflammation levels and estimating cardiovascular risk. However, current CRP detection methods rely on monoclonal antibodies (mAb), which possess shortcomings such as a lengthy preparation cycle, high cost, and poor repeatability. To address these challenges, we explored the potential of peptide aptamers as an alternative to mAb for CRP detection. Using some bioinformatics approaches, we designed and optimized peptide aptamers, selecting the dominant peptide aptamer C9m (KWRWRFRLSR) through experimental validation for its specific recognition of CRP. We then established a sandwich ELISA detection system combining C9m with CRP mAb. This system demonstrated a detection limit of 22.275 ng/mL CRP and exhibited excellent specificity, with no cross-reactivity observed with human serum albumin or γ-globulin. The method also showed high reproducibility, with intra- and inter-assay coefficients of variation (CV) less than 15 %, meeting laboratory testing standards. Furthermore, comparison with clinically used immunoturbidimetry revealed high consistency (r = 0.9891).