Ammonium sulfate - Suitable for molecular biology, ≥99% , CAS No.7783-20-2

CAS: 7783-20-2 Cat. No.: A112103 Formula: (NH₄)₂SO₄ Molecular Weight: 132.14 EC Number: 231-984-1

GRADE & PURITY Suitable for molecular biology, ≥99%

Synonyms

Ammonium sulfate ((NH4)2SO4) | Ammonium sulfate, 99+% (ACS) | AMMONIUM SULPHATE (2:1) | AMMONIUM SULFATE | Ammonium sulfate, ultrapure | Ammonium Sulfate ACS grade | CHEBI:62946 | Sulfuric acid-d2, di(ammonium-d4) salt (8CI,9CI) | BFNBIHQBYMNNAN-UHFFFAOYS

Storage

Room temperature

Shipped In

Normal

Overview

Ammonium sulfate is a versatile inorganic sulfate salt, plays crucial role in biochemical research, molecular biology, and cell culture. It serves as an indispensable tool for purifying antibodies and precipitating or fractionating proteins. Furthermore, it is instrumental in crystallographic analysis of nucleic acids and proteins and also used as a nitrogen supplement in synthetic laboratory media. Our premium-grade Ammonium Sulfate is meticulously crafted to be DNase, RNase, and Protease-free, ensuring its suitability for cutting-edge research.

Specifications

Synonyms

Ammonium sulfate ((NH4)2SO4) | Ammonium sulfate, 99+% (ACS) | AMMONIUM SULPHATE (2:1) | AMMONIUM SULFATE | Ammonium sulfate, ultrapure | Ammonium Sulfate ACS grade | CHEBI:62946 | Sulfuric acid-d2, di(ammonium-d4) salt (8CI,9CI) | BFNBIHQBYMNNAN-UHFFFAOYS

Specifications & Purity

Suitable for molecular biology, ≥99%

Application

Ammonium sulfate helps in quick precipitation of celluar proteins. Ammonium sulfate may be used for the precipitation or fractionation of proteins or for purification of antibodies. It is also useful for crystallographic analysis of nucleic acids and prot

Storage

Room temperature

Shipped In

Normal

Grade

Suitable for molecular biology

Purity

≥99%

Names and Identifiers

Pubchem Sid

488195668

Pubchem Sid Url

https://pubchem.ncbi.nlm.nih.gov/substance/488195668

Canonical Smiles

[NH4+].[NH4+].[O-]S(=O)(=O)[O-]

IUPAC Name

diazanium;sulfate

InChIKey

BFNBIHQBYMNNAN-UHFFFAOYSA-N

INCHI

1S/2H3N.H2O4S/c;;1-5(2,3)4/h2*1H3;(H2,1,2,3,4)

Isomeric SMILES

[NH4+].[NH4+].[O-]S(=O)(=O)[O-]

WGK Germany

1

RTECS

BS4500000

Molecular Weight

132.14

Reaxy-Rn

11343144

Reaxys-RN_link_address

https://www.reaxys.com/reaxys/secured/hopinto.do?context=S&query=IDE.XRN=11343144&ln=

Taxonomic Classification

Taxonomy Tree

• Kingdom Inorganic compounds
  • Superclass Homogeneous non-metal compounds
    • Class Non-metal oxoanionic compounds
      • Subclass Non-metal sulfates

• Kingdom: Inorganic compounds
• Superclass: Homogeneous non-metal compounds
• Class: Non-metal oxoanionic compounds
• Subclass: Non-metal sulfates
• Intermediate Tree Nodes: Not available
• Direct Parent: Non-metal sulfates
• Alternative Parents: Organic sulfuric acids Inorganic oxides
• Molecular Framework: Not available
• Substituents: Non-metal sulfate - Sulfuric acid - Inorganic oxide
• Description: This compound belongs to the class of inorganic compounds known as non-metal sulfates. These are inorganic non-metallic compounds containing a sulfate as its largest oxoanion.
• External Descriptors: ammonium salt - inorganic sulfate salt

Data sources

1. Djoumbou Feunang Y, Eisner R, Knox C, Chepelev L, Hastings J, Owen G, Fahy E, Steinbeck C, Subramanian S, Bolton E, Greiner R, and Wishart DS. ClassyFire: Automated Chemical Classification With A Comprehensive, Computable Taxonomy. Journal of Cheminformatics, 2016, 8:61.

DOI: 10.1186/s13321-016-0174-y

Chemical and Physical Properties

• Solubility: Soluble in water. Insoluble in alcohol and acetone
• Sensitivity: Moisture sensitive.
• Melt Point(°C): >280 °C
• Molecular Weight: 132.140 g/mol
• Hydrogen Bond Donor Count: 2
• Hydrogen Bond Acceptor Count: 4
• Rotatable Bond Count: 0
• Exact Mass: 132.02 Da
• Monoisotopic Mass: 132.02 Da
• Topological Polar Surface Area: 90.600 Ų
• Heavy Atom Count: 7
• Formal Charge: 0
• Complexity: 62.200
• Isotope Atom Count: 0
• Defined Atom Stereocenter Count: 0
• Undefined Atom Stereocenter Count: 0
• Defined Bond Stereocenter Count: 0
• Undefined Bond Stereocenter Count: 0
• The total count of all stereochemical bonds: 0
• Covalently-Bonded Unit Count: 3

XLogP3

Application Protocols

No manufacturer-verified, item-specific application protocols were provided for this SKU. The following are high-level, literature-based outlines; adapt to your system and consult detailed methods.

• Example: 0–60% ammonium sulfate cut for protein enrichment (literature)

  • Cool sample and salt to 4 °C. While stirring, add ammonium sulfate to reach desired percent saturation (consult tables). Equilibrate 30 min, centrifuge 15 min at ~15,000 × g. Collect pellet (or supernatant) as dictated by your target’s solubility.

• Example: Preparing saturated stock at 4 °C (literature)

  • Add excess solid ammonium sulfate to ice-cold ultrapure water, stir until no more dissolves, confirm temperature, decant supernatant, and filter-sterilize (0.22 µm). Store tightly capped to minimize evaporation and crystallization.

• Example: HIC loading buffer setup (literature)

  • Prepare buffer (e.g., 50 mM phosphate, pH 7.0) and adjust to 1.0–1.5 M ammonium sulfate. Clarify by filtration before column loading to maximize binding and reduce fouling.

Note: Validate recovery, activity, and purity for your specific biomolecule. For RNase/DNase-sensitive applications, confirm the grade on the CoA for this lot.

Biological Roles

• General biochemical context (literature)

  • The ions derived from ammonium sulfate participate in fundamental cellular chemistry: ammonium (NH4+) is a conjugate acid of ammonia, entering nitrogen assimilation pathways (e.g., glutamine synthetase/glutamate dehydrogenase), while sulfate (SO4)2− is a source for sulfur assimilation (APS/PAPS pathways) leading to cysteine and sulfate ester biosynthesis in organisms capable of assimilation.
  • In vitro, high concentrations modulate protein solvation and hydration shells, reflecting Hofmeister series behavior; sulfate is strongly kosmotropic, promoting structure formation in water and stabilizing folded states at moderate ionic strength.

• Practical implications for lab workflows (literature)

  • At moderate concentrations, can stabilize some enzymes by suppressing proteolysis and aggregation; at higher concentrations, drives precipitation enabling purification and fractionation.
  • Ammonium vs. sodium/potassium counterions: Ammonium can slightly acidify solutions and may volatilize as ammonia at elevated pH; this can be advantageous or detrimental depending on the assay.

• Not a biological buffer per se

  • Ammonium sulfate solutions exhibit limited buffering capacity; pH is governed by ammonium/ammonia equilibrium and background buffer components.

Note: These are general biological roles of the ions; they do not constitute clinical or therapeutic claims.

Buffer Applications

Ammonium sulfate is not a dedicated buffering agent; however, it is routinely used to set ionic strength and drive precipitation in aqueous systems.

• Practical use in solutions (literature)

  • Percent saturation concept: Protein fractionation relies on the percent saturation of ammonium sulfate in water at a given temperature. Reference saturation tables (e.g., at 0–4 °C) to calculate grams of salt needed per volume of solution for a target cut.
  • pH considerations: Solutions are typically mildly acidic (≈pH 5–6). For pH-sensitive proteins, add ammonium sulfate to an appropriate external buffer (e.g., 50 mM phosphate, HEPES, MES) to maintain pH.
  • Preparation tips: Cool both the sample and solid salt; add salt gradually with gentle stirring to avoid local supersaturation and heat release; verify final volume changes in precise workflows.

• Compatibility (literature)

  • Avoid combining with buffers/ions that generate insoluble sulfates (e.g., Ba2+, Sr2+, Pb2+). With Mg2+ and Ca2+, solubility limits may be approached at high sulfate.

• Example guidance (literature)

  • For a 50% saturation at 4 °C, consult published tables to determine the grams of ammonium sulfate to add per liter of solution; adjust empirically based on sample volume increase after salt addition.

Green Alternatives

Ammonium sulfate is an inorganic salt with relatively low inherent hazard; environmental impacts are primarily related to nitrogen and sulfate loading in wastewater.

• Greenness context (literature)

  • Advantages: Nonflammable, low volatility, minimal worker exposure risk aside from dust; aqueous processing avoids organic solvents.
  • Drawbacks: High salt waste streams require appropriate disposal; eutrophication potential if discharged untreated.

• Alternatives by function (literature)

  • Protein precipitation:
    • PEG precipitation: Lower ionic strength waste; often milder to proteins; can be more expensive; PEG removal may be necessary downstream.
    • Organic solvents (ethanol/isopropanol/acetone): Effective but flammable; may denature sensitive proteins and introduce VOC emissions.
    • Ammonium acetate or sodium sulfate: Different selectivity/solubility; may ease downstream desalting but can have lower efficiency.

• Comparison snapshot (literature)

  • Ammonium sulfate: High selectivity via Hofmeister effect; inexpensive; generates high-salt effluent.
  • PEG: Tunable by MW/concentration; gentle; polymer carryover.
  • Alcohols: Rapid precipitation; safety and denaturation concerns.

Recommendations

• Implement salt recovery or high-capacity desalting (e.g., diafiltration) to reduce wastewater impact.
• Opt for lower-salt precipitants (PEG) when compatible with product quality and process economics.

Pharmaceutical Uses

No therapeutic or clinical claims are made for this product. The following reflects general, non-clinical manufacturing and analytical contexts.

• Bioprocessing roles (literature)

  • Protein capture and fractionation: Employed in upstream/downstream processing to precipitate target proteins or remove impurities via selective cuts.
  • Crystallization: Common precipitant in protein crystallography supporting structure-based drug discovery.
  • Chromatography interfacing: High-salt load conditions (e.g., 1–2 M) can promote binding in hydrophobic interaction chromatography (HIC); subsequent step-down gradients aid elution.

• Formulation/excipient context (literature)

  • Occasionally used to stabilize enzymes during intermediate storage (not as a final dosage excipient). Final drug products rarely contain high ammonium sulfate due to patient safety and compatibility considerations; extensive desalting is standard.

• Regulatory/quality notes

  • For cGMP use, confirm compliance of the specific lot with relevant pharmacopeial monographs if required by your process. For this SKU: only “Suitable for molecular biology” is stated; pharmacopeial status is Not specified for this item; refer to CoA/Spec Sheet.

• Handling in GMP environments

  • Control bioburden and particulates by sterile filtration of solutions; document solution preparation parameters (temperature, pH, percent saturation). Validate removal (diafiltration/dialysis) to defined residual limits.

Physical Properties

• Item-specific (from Product Data)

  • Appearance: Not specified for this item; refer to CoA/Spec Sheet.

• Literature/general properties (for professional reference; not specifications for this lot)

  • Physical state: White crystalline solid (literature)
  • Melting/decomposition: Decomposes on heating; reports indicate onset >235 °C with evolution of ammonia and sulfur oxides (literature)
  • Density: ~1.77 g/cm³ at 20 °C (literature)
  • Hygroscopicity: Slightly hygroscopic; cakes on prolonged exposure to humid air (literature)
  • Solubility (water): Highly soluble; approximate solubility increases with temperature (e.g., ~70 g/100 g H2O at 0 °C to >100 g/100 g H2O near 100 °C) (literature)
  • Solubility (organic solvents): Practically insoluble in most common organic solvents (ethanol, acetone, ether) (literature)
  • Aqueous solution pH: Typically mildly acidic (≈5.0–6.0 at moderate concentrations, due to ammonium acidity) (literature)
  • Refractive index: Not applicable (solid); saturated solutions n varies with concentration (literature)
  • Partition coefficient (logP): Not applicable to inorganic salt; distribution governed by ionic hydration (literature)

Notes

• Values above are provided for planning and method development. Do not treat as item-specific specifications. For certificate-based values, impurities, or solution assay, see the product’s CoA/Spec Sheet.

Quality & Grades

• Item-specific (from Product Data)

  • Grade/Purity: Suitable for molecular biology

• What “Suitable for molecular biology” typically implies (general guidance; not specifications for this lot)

  • Low nuclease burden: Typically screened to be free of detectable DNase/RNase and often protease activity to enable use in nucleic acid and protein workflows.
  • Low organic/metallic contaminants and particulates to minimize interference with enzymatic reactions and spectrophotometric assays.
  • Filtration or fine crystalline form to improve dissolution and solution clarity.

• Practical implications

  • Appropriate for protein precipitation/crystallization, salt-out extraction steps, and preparation of high-ionic-strength buffers used in molecular cloning and biochemistry.
  • For highly sensitive applications (e.g., crystallography, single-molecule studies), verify exact impurity limits, bioburden, and nuclease specifications on the CoA.

• Not provided for this specific item (consult CoA/Spec Sheet)

  • Assay (%), water content, heavy metals/trace metals, UV absorbance, bioburden/endotoxin, stabilizers/anti-caking agents (if any).

Selection tip

• If your protocol mandates specific limits (e.g., RNase-free verified), confirm the stated limits on the CoA for this SKU before use.

Reaction & Applications

• Protein fractionation and precipitation (literature)

  • Widely used for “salting-out” based on the Hofmeister series. Ammonium sulfate is strongly kosmotropic, reducing protein solvation to precipitate proteins selectively by percent saturation.
  • Typical workflow: Sequential cuts (e.g., 0–30%, 30–60%, 60–90% saturation) at 0–4 °C, with gentle stirring and equilibration (15–60 min) before centrifugation.
  • Tips: Maintain cold conditions to preserve activity; adjust pH near protein stability optima; add salt slowly to avoid local supersaturation/denaturation.

• Protein crystallization (literature)

  • Common precipitant in vapor diffusion and batch crystallization screens. Its high ionic strength and sulfate kosmotropy promote nucleation for many proteins.
  • Consider screening across 0.5–2.0 M and pH 4–9 depending on protein isoelectric point; pair with additives (e.g., PEGs, salts) as needed.

• Nucleic acid-related uses (literature)

  • Can assist in phase separation in phenol–chloroform extractions and modulate ionic strength in certain DNA/RNA precipitation workflows (less common than NaOAc/EtOH).

• Aqueous biphasic systems and extractions (literature)

  • Employed to form aqueous two-phase systems with polymers (e.g., PEG) for partitioning biomolecules and cells.

• Process and analytical uses (literature)

  • Stabilizes some enzymes during storage at moderate ionic strengths; can be used to suppress non-specific interactions in chromatography loading buffers.

Note: No manufacturer-specific applications were provided for this item; above are general, literature-based uses.

Reaction Conditions

Because ammonium sulfate primarily serves as a precipitant/ionic-strength modifier rather than a classical reactant, “reaction conditions” here focus on precipitation and crystallization workflows (literature guidance).

• Protein precipitation (salting-out)

  • Temperature: 0–4 °C to preserve activity and improve selectivity.
  • Addition: Slow addition of finely divided solid or concentrated stock solution (e.g., saturated at 4 °C) with gentle stirring.
  • Equilibration: 15–60 min after each incremental addition; verify complete equilibration before centrifugation.
  • Centrifugation: 10,000–20,000 × g for 10–30 min (bench scale) depending on pellet characteristics.
  • Desalting: Resuspend pellet and dialyze or diafilter to remove sulfate and ammonium.

• Protein crystallization

  • Concentration range: 0.5–2.5 M commonly screened; precise values are protein-dependent.
  • pH: Broadly 4–9; select based on protein pI and stability.
  • Method: Vapor diffusion (sitting/hanging drop) or batch; equilibrate at constant temperature (e.g., 18 °C or 4 °C).

• Aqueous two-phase systems (ATPS)

  • Combine PEG (various MW) with ammonium sulfate to form two phases; adjust polymer/salt to tune partition coefficients.

These parameters are typical literature values for planning. Optimize empirically and consult primary protocols for your target macromolecule.

Safety & Handling

• Item-specific (from Product Data)

  • GHS classification, signal word, H-statements, pictograms: Not specified for this item; refer to SDS.
  • Storage conditions: Room temperature (per Product Data)
  • Shipping: Shipped under normal conditions (per Product Data)

• General safety information (literature; consult SDS for authoritative guidance)

  • Hazard overview: Typically considered of low acute toxicity; may cause eye/skin/respiratory irritation, especially as dust. Thermal decomposition can release ammonia and sulfur oxides.
  • PPE: Wear lab coat, safety glasses/goggles, and suitable gloves (e.g., nitrile). Use dust control measures; avoid generating aerosols.
  • Engineering controls: Handle solid in a well-ventilated area; use a fume hood for weighing large quantities or preparing concentrated solutions.
  • Incompatibilities: Strong oxidizers, strong bases (promote ammonia evolution), nitrites (risk of nitrosamine formation in some matrices), and reactive metals in presence of moisture (literature).
  • First aid (overview):
    • Inhalation: Move to fresh air; seek medical attention if symptoms persist.
    • Skin/eye contact: Rinse with water for several minutes; remove contaminated clothing.
    • Ingestion: Rinse mouth; avoid inducing vomiting; seek medical attention if unwell.
  • Fire response: Product is nonflammable, but packaging may burn. Decomposition products can be irritating/toxic; firefighters should use self-contained breathing apparatus.

Always defer to the product SDS for current classification, exposure limits, and detailed first-aid measures.

Solvent Selection

This product is a solid inorganic salt rather than an organic solvent; “solvent selection” is not directly applicable.

• Practical guidance (literature/general)
  • Dissolution medium: Use ultrapure water (e.g., 18 MΩ·cm) for molecular biology workflows. Solutions can be sterile-filtered (0.22 µm) to remove particulates.
  • Ionic strength control: Ammonium sulfate is employed to adjust ionic strength or to induce protein “salting-out.” Choice of solvent is thus about aqueous buffer composition (pH, co-salts) rather than selecting among organic solvents.
  • Buffer compatibility: Compatible with many neutral buffers (e.g., phosphate, HEPES) but note that high sulfate can precipitate with certain multivalent cations (e.g., Ba2+, Pb2+). Avoid buffers that significantly shift ammonium/ammonia equilibrium to ammonia (high pH) if volatilization is a concern.

Alternatives

• If a protocol demands organic precipitation, consider ethanol/isopropanol or acetone precipitation (for nucleic acids/proteins), or PEG precipitation, noting different selectivity and recovery behavior.

Storage & Reconstitution

• Item-specific (from Product Data)

  • Storage conditions: Room temperature
  • Shipped in: Normal conditions

• General storage guidance (literature; apply good laboratory practice)

  • Solid: Store in a tightly sealed container to minimize moisture uptake and caking. Desiccant use is beneficial in humid environments. Protect from large temperature swings that can promote condensation.
  • Shelf life: Inorganic salts are typically stable for extended periods when kept dry; however, always refer to the lot-specific CoA for any assigned retest date.

• Reconstitution and solution handling (literature)

  • Water quality: Use nuclease-free, ultrapure water for molecular biology applications.
  • Filtration: Filter-sterilize solutions (0.22 µm) to remove particulates and bioburden.
  • Concentrated stocks: Prepare at working molarity or percent saturation appropriate for your workflow (e.g., saturated at 4 °C for rapid salting-out steps). Label with temperature, concentration, and preparation date.
  • Storage of solutions: Store tightly capped at room temperature or 2–8 °C depending on concentration and microbial control strategy. Highly concentrated solutions may crystallize upon cooling; warm gently and mix to re-dissolve if needed.
  • Avoid repeated freeze–thaw of solutions; not necessary for inorganic salts and may cause crystallization/precipitation artifacts.

For any item-specific attributes (appearance, assay, impurity limits), Not specified for this item; refer to CoA/Spec Sheet.

Structure & Identity

Ammonium sulfate is an inorganic, highly ionic sulfate salt composed of two ammonium cations and one sulfate anion.

• Item-specific (from Product Data)

  • Product name: Ammonium sulfate (SKU: A112103)
  • CAS: 7783-20-2
  • CID: 6097028
  • InChIKey: 23496 (as provided)
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.

• Literature/computed identifiers (general reference; not item-specific specs)

  • Molecular formula: (NH4)2SO4
  • Average molecular weight: ~132.14 g/mol (literature)
  • Common synonyms: Diammonium sulfate; Ammonium sulphate

• Structural features (descriptive, literature)

  • Ionic compound consisting of two tetrahedral ammonium ions [NH4]+ electrostatically associated with a tetrahedral sulfate dianion [SO4]2−.
  • No stereocenters; no covalent C–H framework. Extended ionic lattice in the solid state.
  • 2D depiction: Central S atom double-bonded to two O atoms and single-bonded (formally) to two O− atoms; charge-balanced by two [NH4]+ counterions placed near the anionic oxygens.

Synthetic Utility

• Role as a kosmotropic electrolyte (literature)

  • In organic and medicinal chemistry workflows, ammonium sulfate is used to “salt out” water from mixtures, facilitating phase separation during extractions and improving recovery of moderately water-soluble organics.

• Workup and purification (literature)

  • Brine replacement: Concentrated ammonium sulfate solutions can outperform NaCl brine for collapsing emulsions and extracting polar organics into organic phases.
  • Protein/biomacromolecule removal: Precipitation from fermentation broths or cell lysates prior to downstream chromatographic purification.

• As a reagent/auxiliary (literature)

  • In certain oxidative systems, sulfate acts as an inert counterion; ammonium ion can serve as a transient base/acid pair in buffered conditions. Limited direct use as a stoichiometric reagent compared with ammonium acetate or ammonium carbonate, but valuable in establishing controlled ionic environments.

• Inorganics/materials (literature)

  • Precursor for mixed sulfate salts (e.g., alums) and in some crystallization-driven separations.

Note: For direct synthetic transformations, alternatives such as ammonium acetate (for acylations/condensations) or ammonium carbonate (as ammonia source) are more reactive; ammonium sulfate’s principal value is in workup, separations, and bioprocess interfacing.

Target Specificity

Not applicable. This product is a simple inorganic salt, not a biological targeting reagent (e.g., antibody, ligand, inhibitor). It exhibits no target specificity beyond general ionic-strength and Hofmeister effects on macromolecules.

Frequently Asked Questions

What is the purity of this product?

This product is supplied at ≥99% purity (chemical assay). Lot-specific values are stated on the Certificate of Analysis.

How should this product be stored?

Store at room temperature.

What does Suitable for molecular biology mean?

Suitable for molecular biology indicates that the product has been processed and tested for molecular biology and proteomics. Typical specifications include low or undetectable nuclease/protease activity, low endotoxin, controlled microbial limits and high lot-to-lot reproducibility.

How is this product shipped?

This product ships under standard ambient conditions. No temperature-controlled packaging is required.

What are the CAS number, molecular formula and molecular weight?

The CAS Number is 7783-20-2, the molecular formula is H8N2O4S, and the molecular weight is 132.14 g/mol. InChIKey BFNBIHQBYMNNAN-UHFFFAOYSA-N.

What documentation is provided?

Available product documentation, including Certificates of Analysis (COA), Safety Data Sheets (SDS), and specification sheets, is shown in the product document area. Document availability and access follow the current site policy.