• Various species
• High sensitivity
• Rapid detection within 2.5 hours
• Good characteristics in terms of linearity, stability, precision, and spiking & recovery

Digoxin (DIG) is a once-daily medication used to treat certain heart conditions when first-line therapies are ineffective or when additional treatment is required. Because digoxin has a narrow therapeutic index, careful monitoring is essential. Excessive digoxin levels can lead to dangerous, and sometimes fatal, cardiac arrhythmias. Therefore, serum digoxin testing helps ensure that drug levels are sufficient to provide therapeutic benefit while avoiding toxicity.

The RayBio^® DIG Enzyme Immunoassay (EIA) Kit is a competitive immunoassay that quantifies DIG in serum or plasma from human, mouse, rat, equine, and bovine samples, as well as urine samples within 2.5 hours. Absorbance is measured at 450 nm, and concentrations are interpolated from a ready-to-use DIG standard curve. The assay demonstrates a sensitivity of 0.0427 ng/ml and has been validated for linearity, stability, precision, and spike-recovery performance. Each kit provides sufficient reagents to perform up to 96 assays, including standard curve and unknown samples.

• Microplate reader capable of measuring absorbance at 450 nm
• Precision pipettes to deliver 2 µL to 1 mL volumes
• Adjustable 1-25 mL pipettes for reagent preparation
• 100 mL and 1-liter graduated cylinders
• Distilled or deionized water
• Tubes to prepare standard or sample dilutions
• Orbital shaker
• GraphPad Prism or SigmaPlot software

1. Prepare all reagents, samples and standards as instructed.
2. Add 50 µL standards or samples to appropriate well. Incubate for 10 minutes at room temperature.
3. Add 50 µL anti-DIG to appropriate well. Incubate 1 hour at room temperature. And wash 5 times.
4. Add 100 µL prepared HRP-Secondary antibody solution. Incubate 1 hour at room temperature. And wash 5 times.
5. Add 100 µL TMB One-Step Substrate Reagent to each well. Incubate 10-25 minutes at room temperature.
6. Add 50 µL Stop Solution to each well. Read at 450 nm immediately.