Buffer and Reagent Preservative: Add 5% (w/v) Sodium Azide stock to prepare 0.02–0.1% working solutions that prevent microbial growth in PBS, TBS, ELISA wash buffers, and antibody diluents (avoid with HRP-conjugates).

Flow Cytometry/Staining Buffers: Used as a preservative in FACS staining and wash buffers to maintain sample integrity during storage and handling.

Quenching Peroxidase Activity: Inhibits horseradish peroxidase (HRP) to stop peroxidase-based reactions in Western blotting and immunohistochemistry.

Mitochondrial Respiration Studies: Inhibits cytochrome c oxidase to probe oxidative phosphorylation, ATP synthesis, and apoptosis pathways.

Selective Agent in Microbiology Media: Suppresses Gram-negative growth (e.g., Escherichia coli, Pseudomonas aeruginosa) and enriches for enterococci on azide-containing media.

BOD5 and Water Testing: Inhibits nitrifying bacteria (e.g., Nitrosomonas, Nitrobacter) to prevent nitrite oxidation during biochemical oxygen demand measurements.

Enzyme Mechanism Controls: Used as a heme-enzyme inhibitor (e.g., catalase, peroxidases) to dissect redox enzyme contributions in biochemical assays.

Sample and Stock Preservation: Maintains sterility of stored lab solutions and reference standards without refrigeration by deterring microbial contamination.

Immunoassay Reagent Stability: Extends shelf-life of non-peroxidase immunoreagents and coating buffers by preventing bacterial proliferation.

Working Solution Preparation: 5% (w/v) Sodium Azide stock enables rapid, accurate dilution to common preservative levels for routine lab use.