A cost-effective chemiluminescent biosensor capable of early diagnosing cancer using a combination of magnetic beads and platinum nanoparticles.

Using thyroid stimulant hormone (TSH) detection antibody-conjugated horseradish peroxidase (HRP) immobilized on platinum (Pt) nanoparticle, a highly sensitive biosensor designed based on the principle of 1,1'-oxalyldiimidazole chemiluminescent enzyme immune assay (ODI CLEIA) was developed for the early diagnosis of thyroid cancer. Trace levels of TSH in human serum was rapidly quantified with the highly sensitive biosensor. The time necessary for the quantification of TSH using the biosensor with ODI CL detection was at least 3 times more rapid than commercially available enzyme immunoassay with colorimetric detection. The linear calibration curve (0.013-12mUL-1) of biosensor obtained with 3-6% coefficient of variation was wider than that of the commercial product. Also, the limit of detection (LOD=background +3σ, 0.005mUL-1) of biosensor was about 100-fold lower than that of commercial enzyme immunoassay. We expect that the newly developed biosensor, which has excellent accuracy, precision, and reproducibility, can be applied as a new method for the early diagnosis of thyroid cancer.