What is likely to cause a falsely low result when using the BCG dye binding assay for albumin?

The BCG (bromocresol green) dye binding assay is a widely used method for measuring albumin levels in biological samples. One important consideration in this assay is how different substances in the sample can interfere with the accurate measurement of albumin.

The presence of penicillin can bind to the dye used in the BCG assay, which may lead to a falsely low measurement of albumin. This binding reduces the amount of dye that is available to bind with albumin, thereby underrepresenting the actual concentration of albumin in the sample. The interference caused by penicillin can occur because it has a structural similarity that allows it to compete with albumin for binding sites on the dye.

Other factors, such as excessive protein concentration, improper assay calibration, or high levels of bilirubin, can indeed affect the assay's accuracy; however, they do not directly cause the same type of interference as penicillin. Excessive protein concentration might lead to spectral interference or decrease assay sensitivity, but not necessarily produce consistently low albumin results. Improper calibration can lead to inaccuracies in results but does not specifically relate to the interference mechanism observed with penicillin. High bilirubin levels can affect the assay through light absorption issues but typically lead to falsely elevated results rather