Development of a Point-of-Care Test Based on Selenium Nanoparticles for Heart-Type Fatty Acid-Binding Proteins in Human Plasma and Blood

Purpose: A rapid, convenient, cost-effective in-home test method for identifying heart-type fatty acid-binding protein (H-FABP) in plasma and blood by a lateral-flow immunoassay (LFIA) based on selenium nanoparticles (SeNPs) was developed. Methods: SeNPs were synthesized by using L-ascorbic acid to reduce seleninic acid at room temperature and conjugated with an anti-H-FABP monoclonal antibody. The limit of detection, specificity, and stability were measured, and clinical samples were analyzed. Results: The SeNPs were spherical with a diameter of 39.48 +/- 3.72 nm and were conjugated successfully with an anti-H-FABP antibody, resulting in a total diameter of 46.52 +/- 2.95 nm. The kit was designed for the determination of H-FABP in plasma specimens and whole blood specimens. The limit of detection was 1 ng/mL in plasma and blood, and the results could be determined within 10 min. No cross-reaction occurred with cardiac troponin I, creatine kinase-MB or myoglobin. The kits were stored at 40 degrees C for up to 30 days without significant loss of activity. The sensitivity was determined to be 100%, the specificity 96.67%, and the overall coincidence rate 97.83%. Conclusion: This SeNP assay kit can conveniently, rapidly, and sensitively detect H-FABP in plasma or blood with a readout of a simple color change visible to the naked eye with no special device, and can be used as an auxiliary means for the early screening of AMI. Clinical Trial Registration: Plasma and blood samples were used under approval from the Experimental Animal Ethics committee of the Joint National Laboratory for Antibody Drug Engineering, Henan University. The clinical trial registration number was HUSOM-2019-047.

Automated summary

A rapid, convenient, and cost-effective in-home test method for identifying heart-type fatty acid-binding protein (H-FABP) in plasma and blood has been developed using selenium nanoparticles. This method can sensitively detect H-FABP with a simple color change visible to the naked eye within 10 minutes, making it a useful auxiliary means for early screening of acute myocardial infarction (AMI).