Western Blotting: Commonly used as a wash buffer (TBS or TBST) to reduce nonspecific binding and maintain protein integrity during transfer and probing.

ELISA: Serves as a plate wash and antibody diluent to minimize background and preserve antigen–antibody interactions.

Immunohistochemistry/Immunocytochemistry: Used for tissue and cell washing, and as an antibody diluent to maintain physiological pH and ionic strength.

Protein Sample Preparation: Provides a stable, isotonic environment for protein dilution, storage, and preparation of blocking solutions.

Immunoprecipitation: Employed in wash steps to maintain pH and ionic strength, improving specificity of antigen–antibody binding.

General Laboratory Buffer: Utilized for routine washing, dilution, and reagent preparation where a pH 7.4 buffering system is required.