Biomarker Sandwich ELISA Simulator

Sandwich ELISA is the workhorse assay behind most clinical protein biomarkers — PSA for prostate cancer, troponin for heart attack, CRP for inflammation. This simulator visualizes the two binding steps that make it work: biomarker antigens diffusing through a microplate well until they stick to antibody-coated capture sites on the floor, followed by enzyme-linked detection antibodies that can only latch onto antigen already held down by a capture antibody. Only that complete three-part "sandwich" lights up and contributes to the signal, which is why the assay stays specific even when the well is crowded. Adjust biomarker concentration, antibody affinity and the diagnostic threshold to see how sensitivity, signal strength and the final positive/negative call all move together.