Thermo Scientific™

Pierce™ Protein-Free (PBS) Blocking Buffer

Catalog number:  37572

 Related applications: Protein Assays and Analysis

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Thermo Scientific Pierce Protein-Free (PBS) Blocking Buffer is a PBS formulation of a non-protein compound that provides effective blocking for membrane-based and plate-based protein detection methods, resulting in extremely low background.

Features of Protein-Free (PBS) Blocking Buffer:

Protein-free blocker—minimizes or eliminates cross-reactivity associated with protein-based blocking buffers
Application-compatible—effective in all kinds of protein detection systems, including Western blots (membranes), ELISA (microplates) and arrays (coated glass slides)
Streptavidin-friendly—absolutely free of biotin; no possible interference with avidin-biotin detection systems
High-performance—optimized and validated in many protein methods to provide high signal-to-noise ratio (i.e., no quenching of specific binding and signal but eliminating nonspecific binding and background)

Traditional blocking buffers contain proteins that can cross-react with immunodetection systems, resulting in high background and reduced signal. Typical commercial alternatives to protein-based blocking agents are ineffective. Pierce Protein-Free Blocking Buffers are devoid of protein while remaining highly effective at blocking plates, membranes and other surfaces for ELISA, Western blotting, glass slide arrays and other applications.

In most experimental situations, blocking buffers based on readily available animal proteins provide the best control and elimination of nonspecific and off-target binding interactions between antibody probes and assay platforms (nitrocellulose or PVDF membranes, polystyrene microplates or glass slides). However, certain sample-and-antibody combinations require the elimination of all possible exogenous animal proteins in the assay system to avoid cross-reaction or quenching of the desired probe function.

Various manufacturers have proposed the use of blocking buffers based on non-mammalian or non-animal proteins, suggesting that plant or bacterial proteins are less likely to cross-react with typical mammalian samples and antibodies. However, our experiments suggest that these non-animal protein blockers do not perform very well compared to Pierce Protein-Free Blocking Buffer, which is completely devoid of proteins (animal or otherwise).

Related Products
Pierce™ Protein-Free T20 (PBS) Blocking Buffer
Pierce™ Protein-Free (TBS) Blocking Buffer
Pierce™ Protein-Free T20 (TBS) Blocking Buffer
For Research Use Only. Not for use in diagnostic procedures.


Form: Liquid
Product Line: Pierce™
Product Size: 1 L
Reagent Type: Blocking Reagent
Validated Application: ELISA, Western Blot

Contents & storage

Upon receipt store product at room temperature. After opening, store product at 4°C.


Manuals & protocols

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