Sigma-Aldrich Phosphate Buffered Saline powder, pH 7.4, with 0.05% Tween® 20

Sigma-Aldrich™ Phosphate Buffered Saline (PBS) Powder with 0.05% Tween® 20, commonly known as PBS-T, is a convenient, high-quality buffer formulation designed for sensitive immunological and molecular biology workflows. Supplied as a dry powder in foil pouches, this reagent provides a reliable and reproducible solution for washing, blocking, and dilution steps in antibody-based assays.

PBS-T combines the stable buffering capacity of phosphate saline at physiological pH 7.4 with the non-ionic detergent Tween 20, which helps minimize nonspecific binding and reduces background signals in immunoassays.

Key Features and Benefits

Stable Physiological Buffer System

The phosphate buffer maintains a consistent pH of 7.4, making it suitable for a wide range of biological assays and protein-based applications.

Enhanced Washing Efficiency

The inclusion of 0.05% Tween® 20 improves washing performance by effectively removing unwanted substances from membranes, microplates, and surfaces.

Reduced Background and Nonspecific Binding

Tween 20 blocks nonspecific protein interactions, helping improve signal-to-noise ratio in immunoassays and antibody detection protocols.

Convenient Powder Format

Supplied as a dry powder in foil pouches for easy preparation, long shelf life, and reduced storage space compared with ready-made liquids.

Reproducible Buffer Preparation

Each pouch is formulated for accurate reconstitution to standard PBS-T composition.

Applications

Sigma-Aldrich™ PBS-T Powder is widely used in:

• Western blotting wash and blocking steps
• Enzyme-linked immunosorbent assay (ELISA) workflows
• Telomere-FISH (Tel-FISH) protocols
• Telomere/immunostaining-FISH (Teli-FISH) applications
• Cell isolation and washing procedures
• General immunoassay buffer preparation

Reconstitution and Final Composition

Dissolve the contents of one foil pouch in 1 L of deionized or ultrapure water to obtain:

• 0.01 M phosphate buffered saline
• 0.138 M NaCl
• 0.0027 M KCl
• 0.05% Tween® 20
• Final pH: 7.4

Packaging

• Supplied in sealed foil pouches to protect against moisture and contamination.

Sigma-Aldrich™ PBS Powder with 0.05% Tween® 20 provides a reliable and convenient solution for preparing PBS-T wash and blocking buffer in immunoassays. With physiological pH stability, optimized ionic strength, and detergent-enhanced background reduction, it is an essential reagent for Western blotting, ELISA, fluorescence in situ hybridization workflows, and cell handling procedures. The powder pouch format ensures reproducibility, easy storage, and efficient laboratory preparation.