Exam 9: Principles for Competitive-Binding Assays

As a preliminary step before performing the assay, some competitive-binding assays either adjust the pH of the patient sample or add an excess of a ligand that is similar to that being measured.Which of the following correctly describes the purpose for these preliminary steps?

The advantage of using europium chelates, as compared to fluorescein, in time-resolved fluorescence competitive-binding assays is:

In a competitive-binding heterogeneous assay, the captive phase involves:

In ____________ competitive-binding assays, paramagnetic particles are used to capture and concentrate bound label on the surface of an electrode.

Which of the following are the two most important characteristics of the fluorophore utilized as the label in fluorescence immunoassays?

What is the purpose of the "label" used in competitive-binding assays?

ELISA is considered a ______ assay, and EMIT is considered a ______ assay.______ assay would be considered more suitable for automated chemistry analyzers.

_______ measures the decrease of incident light transmission as a function of light scatter as the size of the aggregated particles increase, and the use of a ________ detection system increases the analytical sensitivity of these measurements.

The use of avidin-biotin systems in ELISA serve to:

Competitive-binding assays that require the antibody-bound, labeled ligand be physically separated from the free labeled ligand are called ________ techniques.Those techniques that do not require physical separation are called _______ techniques, and these assays require _______.

All of the following are important aspects of competitive-binding assays except:

In microparticle-based light-scattering inhibition immunoassays, as concentration of measured ligand in the patient sample increases, the amount of light scattered in nephelometric measurements ______, and the absorbance reading in turbidimetric measurements ______.

In the fluorescence polarization immunoassay (FPIA) technique, the amount of polarized fluorescent light detected when the fluorophore is excited with polarized light is higher for:

Which of the following best describes the effect of nonspecific binding on the detection limit of an immunoassay?

Which of the following labels is attached to the ligand in the EMIT system?

Suppose your laboratory uses the ELISA configuration in which the antibody has been immobilized onto the solid phase.How would the result of the assay for a patient whose specimen is in a specific well be affected by improperly washing the solid phase of that particular well?

Which of the following data-reduction methods would convert a curved relationship for competitive protein-binding, dose-response relationships to a linear relationship?

In the EMIT system, the absorbance of the product is ______ proportional to the concentration of the unlabeled ligand in the reaction.In the FPIA system, the amount of polarized fluorescent light produced by the reaction is ______ proportional to the concentration of the unlabeled ligand in the reaction.

In competitive-binding assays, the relationship between concentration of unlabeled ligand and percent labeled ligand bound can be described in which of the following ways?

Which of the following approaches to competitive-binding immunoassays would be most likely to improve the sensitivity of the assay for a specific ligand?