Non-invasive detection of Crohn's Disease with label-free detection of calprotectin by impedimetric aptasensor

Crohn's disease, a chronic inflammatory disorder affecting the gastrointestinal tract, is on the rise, posing significant health challenges due to its potential long-term impact on intestinal health. Early and accurate detection of this disease is crucial for effective treatment. This study introduces an innovative approach to diagnosing Crohn's disease by utilizing a rapid and precise biosensor system as an alternative to conventional detection techniques. Utilization of an S100 A8 targeting aptamer for the specific identification of calprotectin, a well-established biomarker associated with Crohn's disease was used as a biorecognition receptor. The aptamer is immobilized on gold nanoparticles via cysteamine and avidin to construct a biosensor. The biosensor was compared with traditional quantitative lateral-flow tests (QLFA). The developed biosensor demonstrates that detection in 900 seconds. Performance parameters, including a limit of detection (LOD) as 5.57 mu g/g and a limit of quantification (LOQ) as 16.89 mu g/g, are determined through electrochemical impedance spectroscopy (EIS). Accordingly, the calibration curve equation was calculated as y=3.9736x + 1570.4 and the regression coefficient was found as R-2=0.9917. These results showed that biosensor's capability to reliably measure calprotectin levels in real samples.