Cardiac troponin I (cTnI) is the gold standard biomarker for myocardial infarction, yet developing highly sensitive assays for troponin detection remains a significant challenge in biomarker research. Standard ELISA methods typically achieve a limit of detection of around 12.5 pg/mL, a threshold that limits their utility in drug development, safety monitoring, and diagnostic assay innovation.
This is where Exazym® reagent kits—powered by our BOLD technology—transform cardiac diagnostics research. During our recent webinar on ultra-sensitive troponin detection, we demonstrated how Exazym® delivers up to 180-fold sensitivity improvement in a cTnI sandwich ELISA, all while using standard laboratory workflows.
The Research Challenge with Troponin
Detecting troponin at ultra-low concentrations is essential for understanding cardiotoxicity in drug development and for creating the next generation of diagnostic assays. Additionally, skeletal troponin can cross-react with cardiac-specific assays, requiring highly specific antibody pairs to ensure accurate cardiac troponin detection. These demands make troponin assay development particularly complex—but also particularly important for researchers and diagnostic developers.
How Exazym® Amplifies Sensitivity
Our approach combines rigorous antibody selection with Exazym®’s BOLD signal amplification. We tested multiple capture and detector antibody combinations, systematically optimizing each parameter: coating conditions, blocking solutions, polymerase concentration, and detection antibody ratios. The result? In a simple buffer, we achieved a limit of detection of 0.07 pg/mL with Exazym®-amplified ELISA—compared to 12.5 pg/mL with standard ELISA. Even more impressively, when tested in 25% serum to mimic real clinical samples, we observed a 180-fold sensitivity improvement. This means researchers can now reliably quantify cardiac troponin at concentrations previously invisible to standard methods.
Real-World Applicability
What makes Exazym® particularly valuable is that it integrates seamlessly into existing workflows. There’s no need for expensive new equipment—you use your current ELISA reader. The assay adds only 10-60 minutes to standard protocols and works with your previously optimized antibody pairs. We even demonstrated that Exazym® works at 37°C, matching the conditions used in automated diagnostic systems—enabling labs to develop ultra-sensitive troponin assays compatible with their current infrastructure.
Implications for Cardiac Research and Beyond
The democratization of ultra-sensitive troponin detection has profound implications for biomarker research. Researchers developing cardiac diagnostics can now detect troponin at previously inaccessible sensitivity levels using Exazym®, accelerating assay development and diagnostic innovation. Beyond cardiology, the same amplification strategy applies to biomarkers in drug discovery, neurodegenerative disease detection, and biomarker research across therapeutic areas.
For researchers developing immunoassays, the key takeaway is clear: ultra-sensitive detection no longer requires choosing between simplicity and performance. Exazym® provides ultra-sensitive detection using the standard immunoassay workflows your lab already knows.
Watch the full webinar recording to see detailed methodology, data, and Q&A with our Principal Scientist, Dr. Peter Stenlund.