Rivalta Reagent - BioReagent

Cat. No.: R1528796

GRADE & PURITY BioReagent, for Protein analysis

Storage

Store at 2-8°C,Protected from light

Shipped In

Wet ice

Application

1093

Overview

Rivalta test, also known as Rivalta reaction, is a qualitative test for serous mucin. The principle is that serous mucin is a complex composed of polysaccharides and proteins. Its isoelectric point is pH 3–5, and it is also called acid glycoprotein. A white precipitate will form when it is added to a large volume of dilute acetic acid, which indicates a positive result. It is used for qualitative detection of serous mucin in serous cavity effusion. The detection principle is that serous mucin produces a white cloudy precipitate under acidic conditions, namely the Rivalta reaction. This reagent is corrosive. Please take anti-corrosion precautions.

Operating Procedure (For Reference Only):

Add 100 mL of reagent into a 100 mL graduated cylinder, drop 1–2 drops of serous cavity puncture fluid, and observe whether a white cloudy turbidity sinks below the 50 mL mark. A positive result is confirmed if this phenomenon occurs.

Precautions:

1. For your safety and health, wear a lab coat and disposable gloves during operation.

2. This product is for research use only. Do not use it for other purposes.

Specifications

Specifications & Purity

BioReagent, for Protein analysis

Stability And Storage

Store at 2-8℃ long term (12 months). Store in the dark.

Storage

Store at 2-8°C,Protected from light

Shipped In

Wet ice

This product requires cold chain shipping. Ground and other economy services are not available.

Grade

BioReagent, for Protein analysis

Product Line

Biological Products

Chemical and Physical Properties

• Sensitivity: Light-sensitive

Application Protocols

No item-specific, validated protocols are provided in the Product Data. The following is a generalized, literature-style protocol for qualitative precipitation screening using a Rivalta-type reagent. Adjust to your SOP and confirm item composition from the CoA.

• Materials

  • Rivalta Reagent (SKU R1528796)
  • Clear test tubes (10–15 mL) or glass vials
  • Micropipette and tips
  • Negative and positive control samples (internal standards)

• Procedure (literature guidance)

  1. Bring reagent and samples to room temperature (20–25 °C).
  2. Aliquot 3–5 mL of reagent into a clear tube.
  3. Gently deliver 30–50 µL of sample onto the liquid surface or along the tube wall to minimize mixing.
  4. Observe for up to 2 minutes without agitation. A persistent, descending cloud or string suggests a positive precipitation response. No persistent turbidity indicates negative.
  5. Document results (photo if possible) and compare to controls.

• QA notes

  • Use consistent drop volume and introduction technique across tests.
  • Replace reagent if turbidity, discoloration, or microbial contamination is observed.
  • Record lot numbers and environmental conditions for traceability.

This protocol is provided for research use only and should be validated in your laboratory.

Biological Roles

This product is a laboratory reagent and does not possess intrinsic biological roles as a metabolite or ligand. However, understanding the biochemical principle underlying its use can aid experimental design.

• Mechanistic basis (literature)

  • Mild acidification of aqueous biological samples shifts protein surface charge, reduces solvation, and can promote aggregation via decreased electrostatic repulsion and enhanced hydrophobic interactions. High–molecular weight glycoproteins/mucopolysaccharides may also flocculate under these conditions.
  • The visible “cloud” or string observed in the Rivalta test represents colloidal aggregates settling through the bulk aqueous phase.

• Factors affecting response (literature)

  • Protein concentration and composition (albumin vs globulins), presence of acute-phase proteins, and extracellular matrix components influence precipitation behavior.
  • Salinity and buffering capacity of the sample can counteract acidification, attenuating the response.
  • Temperature and viscosity alter diffusion and aggregation kinetics, impacting visual endpoints.

• Research context

  • In research laboratories, Rivalta-type precipitation can serve as a rapid qualitative screen for proteinaceous content in complex biological fluids prior to more quantitative proteomic or biochemical analyses.

Note: No clinical or diagnostic claims are made. Use is restricted to research applications, and outcomes should be corroborated with validated analytical methods (e.g., total protein assays, electrophoresis) when quantitative interpretation is required.

Buffer Applications

Rivalta Reagent is not a buffer system; it is an acidic aqueous solution used to induce precipitation/flocculation in qualitative tests. As such, it is not typically selected for buffering cell culture media, electrophoresis, or pH control.

• If your workflow requires controlled pH buffering, consider established buffer systems with defined pKa and buffering ranges (e.g., acetate, phosphate, Tris, HEPES). The choice should match the target pH and downstream assay compatibility.

• For precipitation-based qualitative screening in biological matrices, refer instead to the Reaction & Applications and Reaction Conditions sections for practical guidance.

Green Alternatives

Because Rivalta Reagent is typically an aqueous, dilute-acid preparation, its environmental profile is generally more benign than many strong mineral acid or halogenated systems. Nonetheless, greener-by-design considerations can help optimize lab sustainability.

• Comparative overview (literature; not item-specific)

  | Option | Typical composition | Relative hazard | Waste considerations | Notes | |---|---|---|---|---| | Rivalta reagent (dilute organic acid in water) | Water + weak acid (e.g., acetic acid) | Low to moderate (irritant) | Neutralize to pH 6–8; aqueous drain disposal may be permitted where regulations allow | Minimal VOC at dilute levels; verify local rules | | Sulfosalicylic acid (SSA) | Aromatic sulfonic acid | Moderate; eye/skin irritant | Collect as hazardous aqueous acidic waste | Stronger precipitation; more persistent residues | | Trichloroacetic acid (TCA) | Chlorinated carboxylic acid | Higher; corrosive, toxic | Halogenated organic waste stream | Potent precipitant; greater EHS burden |

• Greening tips

  • Use minimal volumes consistent with your detection needs; miniaturize into microtubes or multiwell plates to cut waste.
  • Standardize protocols to reduce repeats and improve first-pass success.
  • Neutralize acidic waste on the bench (with proper PPE) to reduce downstream treatment burden, then segregate per local regulations.
  • Store at 2–8 °C to maintain quality and reduce unnecessary discards due to degradation or microbial growth.

Always follow your institution’s waste and sustainability policies; the above comparisons are general literature guidance.

Pharmaceutical Uses

This product is a laboratory BioReagent supplied for research use only. It is not produced under GMP, and no pharmacopeial status is claimed in the Product Data.

• Not typically used as an excipient or manufacturing aid in pharmaceutical formulations.
• No claims are made regarding clinical diagnostic use, lot release testing for therapeutics, or patient-contact applications.

If you require a reagent for regulated pharmaceutical workflows, consider verifying:

• Documented compliance with relevant pharmacopeial monographs, where applicable.
• Supplier qualifications, change control, and audit support.
• Composition, bioburden/endotoxin limits, and elemental impurity profiles suited to your intended use.

For SKU R1528796, consult the CoA/Spec Sheet for the exact composition and QC attributes if you intend to develop internal SOPs that interface with regulated environments (e.g., as an in-process qualitative check within research-stage development).

Physical Properties

Item-specific physico-chemical specifications are not provided in the Product Data. The following fields are accordingly left unspecified for this catalog item and should be confirmed from the CoA/SDS.

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Density, pH, refractive index, conductivity: Not specified for this item; refer to CoA/Spec Sheet.
• Water content, UV cutoff, metallic/ionic impurities: Not specified for this item; refer to CoA/Spec Sheet.

General/literature context for typical Rivalta reagents (for planning only; not item specifications):

• Physical state: Aqueous solution (clear, colorless) when freshly prepared with water and a weak acid such as acetic acid.
• Odor: Vinegar-like if acetic acid is present (literature).
• pH: Mildly acidic by design; the exact pH depends on formulation and should be verified for each lot (literature).
• Solubility: Fully miscible with water (literature, for acetic acid–water systems).
• Boiling/Freezing behavior: Governed by water-rich mixture properties; freezing near 0 °C and boiling near 100 °C shift modestly with acid content (literature).

Important: Do not treat the above as specifications for SKU R1528796. Always consult the item-specific CoA/SDS for quantitative properties and acceptance criteria relevant to your method validation or QA documentation.

Quality & Grades

• Item-specific (from Product Data)

  • Grade: BioReagent

• What BioReagent grade implies (general guidance)

  • BioReagent grade materials are suitable for common life-science workflows, providing consistent performance in biological assays and lab protocols. Typical expectations include low levels of particulate and fluorescent impurities, and lot-to-lot consistency that supports qualitative/semiquantitative research use.
  • For a formulated solution like Rivalta Reagent, BioReagent grade generally emphasizes controlled composition, clarity, and microbiological quality appropriate for research settings (not sterile unless specified). It does not imply clinical diagnostic or GMP suitability.

• Documentation and verification

  • Composition, pH range, and acceptance criteria: Not specified for this item; refer to CoA/Spec Sheet for the exact formulation and QC parameters of this SKU.
  • Stabilizers/preservatives: Not specified for this item; refer to CoA/Spec Sheet. If a preservative is present, consider downstream assay compatibility.
  • UV background/fluorescence: Not specified for this item; refer to CoA/Spec Sheet if your method is spectroscopic.

• Practical notes for users

  • Record lot numbers and retain CoAs with experimental records to ensure traceability.
  • If your method is pH- or ionic-strength–sensitive, verify these parameters upon receipt and prior to critical measurements.
  • For regulated work, validate the reagent in-house against your method SOPs; this product is for research use only.

Reaction & Applications

• Item scope

  • Rivalta Reagent (BioReagent grade) is intended for research use as a qualitative precipitation medium. It is not a synthetic reagent for bond-forming reactions.

• Principle and typical laboratory application (literature)

  • The Rivalta test relies on acid-induced precipitation/flocculation of high–molecular weight biomolecules (predominantly proteins, glycoproteins, and mucopolysaccharides) from aqueous biological samples. When a drop of the sample is introduced into the reagent, formation of a persistent, descending “cloud” or string is interpreted as a positive precipitation event.

• Practical tips for research workflows

  • Use clean, clear glassware to observe flocculation. Compare test drops to a blank (reagent alone) and to a negative control sample.
  • Standardize the drop size and introduction height to improve reproducibility. Gentle introduction along the wall of the vessel minimizes turbulence.
  • Temperature can influence viscosity and diffusion; perform tests at a consistent ambient temperature, and equilibrate the reagent and samples beforehand.
  • Consider sample preclarification (low-speed spin) to remove cells/debris that can confound visualization.
  • Document outcomes by imaging or by an ordinal scoring rubric (e.g., negative/trace/positive) suitable for your lab notebook.

• Interferences (literature)

  • High concentrations of detergents, strong buffers, or extreme ionic strengths may suppress or modify precipitation behavior. Hemolysis or lipemia can complicate visual endpoints.

Note: The above are general literature practices. For SKU R1528796, consult the CoA for any composition-specific guidance that may affect behavior.

Reaction Conditions

As a qualitative precipitation reagent, Rivalta Reagent use is governed by observational conditions rather than stoichiometric kinetics. The following guidance reflects general literature practices and should be adapted to your SOP. These are not item-specific specifications.

• Typical setup (literature)

  • Temperature: Ambient (20–25 °C). Maintain consistent conditions across tests.
  • Vessel: Clear glass test tube or conical tube to visualize flocculation.
  • Volume: 2–10 mL reagent per test is common; scale to vessel size to permit clear visualization.

• Procedure outline (literature example)

  • Equilibrate reagent and samples to room temperature.
  • Add a standardized drop (e.g., 20–50 µL) of the sample carefully to the surface or sidewall of the reagent without mixing.
  • Observe for up to 2 minutes for formation of persistent cloud/string descending through the solution.
  • Record as negative/trace/positive per an internal rubric; include a blank and control samples.

• Controls and robustness

  • Include a negative control matrix known to be low in protein to benchmark background.
  • If your samples vary in ionic strength or surfactant content, consider serial dilutions to assess matrix effects.

• Notes

  • The exact pH and acid concentration of the reagent strongly influence sensitivity/specificity; confirm these values for SKU R1528796 from the CoA, and keep them consistent across lots for comparative studies.

Safety & Handling

Item-specific hazard classification and statements were not provided in the Product Data. Always consult the product SDS for authoritative safety information.

• Item-specific (from Product Data)

  • GHS Classification: Not specified for this item; refer to SDS.
  • Signal Word / H-Statements / Pictograms: Not specified for this item; refer to SDS.
  • Storage Conditions: Store at 2–8 °C.
  • Shipped In: Wet ice.

• General safety considerations (literature; for acetic acid–based Rivalta reagents)

  • Hazards: Mildly acidic aqueous solutions can be irritating to skin and eyes; splashes may cause discomfort. Concentrated acetic acid is corrosive; however, Rivalta reagents are typically dilute. Handle according to your institution’s chemical hygiene plan.
  • PPE: Chemical-resistant gloves, lab coat, and safety goggles. Use splash protection when handling bulk volumes.
  • Engineering controls: Work in a well-ventilated area. Fume hood recommended when preparing reagent from concentrated acetic acid.
  • Incompatibilities: Avoid contact with strong bases (neutralization/heat), oxidizers (if other acids present), and reactive metals susceptible to acid corrosion (literature).
  • First aid (overview; defer to SDS): Rinse affected skin/eyes with water for ≥15 minutes; remove contaminated clothing. If inhaled (mists), move to fresh air. If ingested, rinse mouth; seek medical attention.

• Spill/waste

  • Small spills: Dilute with water, neutralize carefully with sodium bicarbonate, and absorb with inert material; dispose per local regulations (literature guidance).
  • Waste: Collect acidic aqueous waste in appropriate containers; label and dispose following institutional and regulatory requirements.

Solvent Selection

This product is a prepared aqueous reagent rather than an organic solvent. Traditional solvent-selection frameworks are not directly applicable. The following general considerations may assist in method planning:

• Polarity and medium

  • The reagent is water-based and mildly acidic (literature for typical Rivalta reagents). It functions as a proton-donating medium to promote colloidal/precipitation phenomena in proteinaceous samples.

• Miscibility profile (literature)

  • Fully miscible with water. Mixing with high levels of organic solvents (e.g., ethanol, acetone) will change precipitation behavior and is not recommended unless validated.

• When to choose Rivalta reagent vs alternatives

  • Choose Rivalta reagent for qualitative protein flocculation/precipitation screens on biological fluids in research settings where a rapid yes/no assessment is sufficient.
  • Consider alternatives when you need sharper selectivity or quantitative endpoints:
    • Trichloroacetic acid (TCA) or sulfosalicylic acid (SSA) for stronger protein precipitation (more aggressive; handle with care).
    • Turbidimetric or dye-binding protein assays (e.g., Bradford) when quantitation is required.

• Compatibility notes

  • High surfactant, high salt, or strongly buffered samples can alter precipitation outcomes. If present, consider diluting or pretreating samples, and always include appropriate controls.

Always verify the exact composition and pH of this item from the CoA to align your protocol and expectations.

Storage & Reconstitution

• Item-specific (from Product Data)

  • Storage Conditions: Store at 2–8 °C.
  • Shipped In: Wet ice.

• Reconstitution/Preparation

  • Supplied form and any reconstitution steps are not specified for this item; refer to CoA/Spec Sheet. If provided as a ready-to-use solution, mix gently before use. If provided as a concentrate, dilute with high-purity water as directed on the CoA while monitoring pH.

• Handling and stability (general guidance)

  • Protect from contamination: Work aseptically where possible. Do not return used aliquots to the stock container.
  • Visual inspection: Discard if precipitate, haze, discoloration, or microbial growth is observed.
  • Temperature excursions: Brief room-temperature handling during use is acceptable; return to 2–8 °C promptly.
  • Freeze–thaw: Avoid freezing unless explicitly permitted on the CoA, as freeze–thaw may change composition or promote gas bubble formation that interferes with visual tests.

• Shelf life

  • Not specified for this item; refer to CoA/Spec Sheet. For best reproducibility, note the receipt date and implement an internal retest period aligned with your QC policy.

Always consult the SDS and CoA for authoritative guidance on storage, stability, and any preparation instructions specific to SKU R1528796.

Structure & Identity

Item-specific identifiers are not provided for this catalog listing. Where helpful, general/literature information about typical Rivalta reagents is noted separately.

• Item-specific (from Product Data)

  • Product Name: Rivalta Reagent
  • SKU: R1528796
  • Grade: BioReagent
  • CAS: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular Formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular Weight: Not specified for this item; refer to CoA/Spec Sheet.
  • SMILES / InChIKey / CID: Not specified for this item; refer to CoA/Spec Sheet.

• General description (literature)

  • “Rivalta reagent” is commonly an aqueous, mildly acidic solution used for qualitative protein precipitation tests (the Rivalta test) in biological fluids. Many literature procedures prepare it as dilute acetic acid in water (e.g., a small amount of glacial acetic acid in distilled water), though exact composition varies by lab SOP.
  • Structural features: as a preparation rather than a single defined molecule, the reagent comprises water plus a weak organic acid (typically acetic acid). No discrete stereochemical features apply.

• 2D structural depiction (literature, if acetic acid–based)

  • Major component: H2O (solvent).
  • Acid component (typical): CH3–C(=O)–OH (acetic acid), containing a carboxylic acid functional group capable of donating a proton to lower solution pH.

Note: Because this is a formulated reagent rather than a pure compound, structure/identity fields such as a single CAS or InChIKey are not generally applicable unless the exact composition is specified on the CoA.

Synthetic Utility

Rivalta Reagent is not a synthetic building block or a reagent for bond-forming/cleaving transformations. It serves as an aqueous acidic medium for qualitative precipitation phenomena.

• Not applicable

  • No direct role in named organic reactions, catalysis, or polymerizations.
  • Not used as a protecting-group reagent or as an oxidant/reductant.

• Indirect utility in workflows (literature)

  • Sample preparation: A rapid screen for proteinaceous content of complex fluids before committing samples to resource-intensive analyses (chromatography, electrophoresis, MS).
  • Method development: Can help assess whether acid-induced precipitation will foul downstream separations, informing pretreatment or filtration needs.

If your aim is chemical synthesis requiring a weak acid, consider well-defined reagents (e.g., glacial acetic acid, formic acid) with specified assay, water content, and impurity profiles appropriate for reaction stoichiometry and reproducibility.

Target Specificity

Not applicable. This product is not an antibody, enzyme inhibitor, ligand, or probe directed toward a discrete molecular target. It is an acidic aqueous reagent used to induce non-specific precipitation/flocculation of macromolecules in complex biological fluids for qualitative research screening.