•Stabilization and Protection:

•Enzyme/Antibody Stabilizer: Encapsulates macromolecules (e.g., enzymes, antibodies) via hydrogen bonding and hydrophobic interactions, preventing denaturation or aggregation and extending active preservation time.

•Protective Colloid: Inhibits aggregation and sedimentation of particles (e.g., latex microspheres, nanogold particles), maintaining the homogeneity of the detection system.

• Dispersion and Solubilization Functions:

•Dispersant: Prevents aggregation of hydrophobic particles (e.g., lipids, insoluble substrates) through steric hindrance, improving reaction efficiency.

•Solubilizer: Increases the solubility of hydrophobic substances (e.g., certain chemiluminescent substrates) in aqueous phases.

•Film-Forming and Sustained Release:

•Film-Forming Ability: Forms a uniform film on the surface of microplates or test strips, protecting active ingredients from environmental interference (e.g., oxidation).

•Sustained-Release Carrier: Controls the release rate of detection reagents (e.g., color development time regulation in POCT test strips) through physical embedding or adsorption.

•Immunoassays:

•ELISA/Chemiluminescence: Used as a component of blocking or dilution buffers to reduce non-specific adsorption (e.g., blocking unbound sites on microplate surfaces).

•Latex-Enhanced Immunoturbidimetry: Stabilizes latex particle-antibody complexes, preventing false positives/negatives caused by aggregation.

•Molecular Diagnostics:

•PCR/qPCR: Inhibits non-specific binding of DNA polymerase, improving amplification specificity.

•Nucleic Acid Extraction: Adsorbs interferents (e.g., phenols, tannins) from samples to purify DNA/RNA (similar to the principle of plant enzyme purification).

•Biochemical Detection:

•Enzymatic Reaction Systems: Stabilizes enzyme activity (e.g., horseradish peroxidase HRP) and prevents substrate auto-oxidation.

•Chromogenic Substrate Preparation: Disperses insoluble chromogenic agents (e.g., TMB) to ensure uniform color development.

•Point-of-Care Testing (POCT):

•Test Strip Coating: Improves the hydrophilicity of nitrocellulose membranes, accelerates sample diffusion, and shortens detection time.

Luvitec  is a trademark of BASF

•Blocking/Dilution Buffer: 0.1%–1% (e.g., 0.5% PVP K30 is commonly used in ELISA blocking buffers).

•Particle Dispersion Systems: 0.5%–3% (e.g., latex particle suspensions).

•Enzyme Stabilizer: 0.1%–0.5% (impact on enzyme activity requires validation).

•Nucleic Acid Purification: 1%–5% (adsorbs phenolic interferents).

•Direct Dissolution: Readily soluble in water and ethanol; stir at room temperature without heating.

•Pre-mixed Storage: Prepare a 10% stock solution to avoid microbial growth during long-term storage.

•Store sealed in a dry, cool place (recommended 15–25°C) to prevent moisture absorption, clumping, or microbial contamination.

•Slight yellowing may occur during long-term storage but does not affect functionality; store protected from light.

•Temperature Sensitivity: High temperatures (>80°C) may cause molecular chain breakdown, losing film-forming ability.

•pH Compatibility: Stable within pH 3–10; may degrade under strongly acidic/alkaline conditions.

•Plastic Containers: Prolonged contact may swell polystyrene (PS) containers; use short-term or switch to glass containers.

•Protein Interference: Excess may adsorb antigens/antibodies; optimize concentration through pre-experiments.

•Strong Oxidizers: May undergo oxidation reactions with high concentrations of persulfates, hypochlorites, etc.

•Polyvalent Cations: May form precipitates when combined with Al³⁺, Fe³⁺, etc.