Ammonium sulfate - UltraBio™, Ultra pure, ≥99% , CAS No.7783-20-2

CAS: 7783-20-2 Cat. No.: A434061 Formula: (NH₄)₂SO₄ Molecular Weight: 132.14 EC Number: 231-984-1

GRADE & PURITY UltraBio™, Ultra pure, ≥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,Desiccated

Shipped In

Normal

Overview

Application

Ammonium sulfate has been used as an additive in salting-out procedure to prepare the g-globulin fraction. It is also used as a component in synthetic minimal dextrose (SD) liquid medium.

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

UltraBio™, Ultra pure, ≥99%

Biochemical and Physiological Mechanisms

Ammonium sulfate ((NH 4 ) 2 SO 4 ) is mainly used as a soil fertilizer. It is also used as a wood preservative. This inorganic salt plays a role in flame retardant chemicals.

Storage

Room temperature,Desiccated

Shipped In

Normal

Grade

Ultra pure, UltraBio™

Purity

≥99%

Names and Identifiers

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: H2O: 1M, clear, colorless
• x_melt_point_char: >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

Item-specific, tested protocols (WB, IHC, IF, FC, etc.) are not applicable to this inorganic salt, and none are provided in the Product Data. For general guidance, consult standard references for:

• Ammonium sulfate precipitation (“cut”) procedures tailored to your protein of interest.
• Salting-out extraction methods for sample cleanup prior to GC/LC analysis.
• Aqueous two-phase system setup using polymer/salt diagrams.

For precise, validated steps, buffer compositions, and saturation tables, refer to established biochemical method manuals and peer-reviewed literature.

Biological Roles

Ammonium sulfate itself is not a metabolite but dissociates into ions with clear biological relevance (literature):

• Ammonium (NH4+):

  • Interconvertible with ammonia (NH3) depending on pH; participates in nitrogen metabolism, including assimilation via glutamine synthetase/glutamate dehydrogenase pathways in microbes and plants.
  • Can modulate enzyme activity and protein stability in vitro by altering ionic strength and hydrogen-bond networks.

• Sulfate (SO4 2−):

  • Essential inorganic sulfur source for many organisms, reduced to sulfide and incorporated into cysteine and methionine via the sulfur assimilation pathway in plants and microbes.

Biochemical utility (literature):

• Protein precipitation and stabilization: High sulfate kosmotropic character promotes water structuring and drives “salting-out,” concentrating proteins while preserving activity in many cases.
• Enzyme assays: Controlled ionic strength with ammonium sulfate can suppress proteolysis, reduce nonspecific interactions, and tune activity coefficients.
• Microbial culture: Occasionally used as a nitrogen and sulfur source in minimal media formulations; selection depends on the organism and desired pH regime.

Note: While biologically relevant ions are involved, ammonium sulfate in this catalog is intended for laboratory research use only. It is not supplied for clinical or diagnostic applications.

Buffer Applications

Ammonium sulfate is not typically used as a primary buffering agent because the NH4+/NH3 conjugate pair has useful buffering capacity only at relatively high pH near the pKa of ammonium (~9.25, literature), where ammonia volatility and protein stability may become concerns. The sulfate anion does not provide appreciable buffering in the biological pH range.

Practical use cases (literature):

• Ionic strength adjustment: Often added to buffered solutions (e.g., phosphate, Tris, HEPES) to increase ionic strength without changing the buffer chemistry.
• Precipitation setups: Employed alongside a chosen buffer to maintain pH while executing “ammonium sulfate cuts.”

Alternatives for buffering (literature):

• For volatile buffer systems compatible with MS or lyophilization, use ammonium acetate (pH ~3.8–5.8) or ammonium bicarbonate (pH ~7.8–8.4).
• For robust biological buffers in the neutral range, use phosphate, HEPES, MOPS, or Tris, and add ammonium sulfate only to tune ionic strength or induce salting-out when required.

Green Alternatives

Assessment (literature): Ammonium sulfate is inorganic, non-volatile, and generally considered low-hazard in laboratory use. Environmental concerns relate mainly to nutrient loading (eutrophication) if released to waterways. From a green chemistry perspective, its use is justified when high ionic strength is essential, but alternatives may be preferable for volatile/low-residue workflows.

Potential alternatives and trade-offs (literature):

• Ammonium acetate or bicarbonate (volatile ammonium salts)

  • Pros: Volatile; easily removed by lyophilization; MS-compatible; lower residue.
  • Cons: Weaker salting-out effect; lower ionic strength ceiling; narrower stability ranges for some proteins.

• Sodium/potassium sulfate or chloride

  • Pros: Widely available; low hazard; effective for generic ionic strength adjustment.
  • Cons: Do not provide ammonium buffering; may change protein behavior differently; non-volatile residues persist.

• Process considerations:

  • Minimize use by optimizing cut ranges to reduce total salt mass.
  • Recycle mother liquors where feasible; consider dialysis water reuse with appropriate treatment.
  • Prevent releases to drains; collect saline waste for appropriate disposal.

Small comparison (literature):

• Property | Ammonium sulfate | Ammonium acetate
• Residue after drying | High (non-volatile) | Minimal (volatile)
• Salting-out strength | Strong | Moderate
• MS compatibility | Poor | Good
• Environmental aspect | Nutrient load if discharged | Organic load but readily removed by evaporation

Pharmaceutical Uses

No therapeutic claims are made. The following describes general formulation and manufacturing contexts (literature):

• Bioprocessing aid: Widely used for upstream concentration and fractionation of protein therapeutics, enzymes, and vaccine antigens by salting-out prior to chromatographic polishing.
• Stabilizer during intermediate holds: Elevated ionic strength can stabilize certain proteins against aggregation or proteolysis during processing steps; removal is subsequently performed by diafiltration/dialysis.
• Excipient status: Not typically used as a final-dosage excipient due to high residual ionic strength and non-volatility; instead, it serves as a process reagent. Pharmacopeial monographs may exist for ammonium sulfate, but compliance specifics for this item are Not specified for this item; refer to CoA/Spec Sheet.

Manufacturing considerations:

• Residuals control: Because ammonium sulfate is non-volatile, robust removal steps (UF/DF) are necessary to meet residual salt specifications.
• Analytics: Monitor conductivity, osmolality, and sulfate/ammonium residuals; choose orthogonal methods (e.g., ion chromatography) when needed.
• Materials compatibility: High-salt solutions can stress stainless steel and elastomers; verify compatibility and rinse protocols in GMP settings.

Physical Properties

Item-specific physical specifications (water content, metal limits, UV cutoff, etc.): Not specified for this item; refer to CoA/Spec Sheet.

Literature/general properties for ammonium sulfate (for reference; not item-specific specs):

• Physical state: Colorless to white crystalline solid; odorless (literature)
• Molecular weight: 132.14 g/mol (literature)
• Density (solid): ~1.77 g/cm³ at 20 °C (literature)
• Melting/decomposition: Decomposes on heating >235–280 °C, releasing ammonia and sulfur oxides; no true boiling point (literature)
• Solubility:
  • Highly soluble in water; forms endothermic solutions (literature)
  • Sparingly soluble to insoluble in typical organic solvents (ethanol, acetone, ethers) (literature)
• Aqueous behavior:
  • Fully dissociates to NH4+ and SO4 2−; strong ionic strength contributor (literature)
  • pH of 1% solutions typically mildly acidic due to NH4+/NH3 equilibrium (literature)
• Hygroscopicity: Slightly hygroscopic; tends to cake on moisture uptake (literature)
• Partitioning: Not applicable (inorganic salt; logP not meaningful)
• Refractive index: Not typically reported for the solid; depends on solution concentration (literature)

Notes for practitioners:

• Because dissolution is endothermic, warm water and stirring markedly accelerate dissolution.
• High solubility enables preparation of saturated solutions for “salting-out” protocols; verify exact saturation curves from reliable solubility tables when designing precipitation cuts.

Quality and Grades

• Item-specific grade: UltraBio™, Ultra pure (per Product Data)

  • Intended for demanding biochemical workflows such as protein fractionation, nucleic acid precipitation, and bioprocessing where background contaminants must be minimized.
  • Typical implications of “Ultra pure/biochemical” grades include tight control of trace metals, organic residues, and insoluble particulates; however, exact numerical limits are not specified for this item; refer to CoA/Spec Sheet.

• What this means in practice:

  • Low background in spectroscopic assays and enzyme work, aiding reproducibility in ammonium sulfate cuts and chromatographic sample prep.
  • Reduced bioburden and particulates to minimize fouling of filtration units and columns.

• Not provided for this item (consult CoA/SDS):

  • Heavy metal content, bioburden/endotoxin, UV absorbance profile, pH of defined solutions, and moisture content. Not specified for this item; refer to CoA/Spec Sheet.

• Fit-for-purpose guidance:

  • For analytical chromatography or MS workflows requiring volatile buffers, consider switching to ammonium acetate/bicarbonate during final steps; use ammonium sulfate upstream for precipitation only.
  • When doing quantitative proteomics, verify lot-to-lot background by preparing blank matrices since even ultra-pure inorganic salts can carry trace contaminants.

Reaction and Applications

Key laboratory applications (literature; expandable from typical manufacturer use):

• Protein fractionation by “ammonium sulfate cut” (salting-out):
  • Exploits reduced protein solubility at elevated ionic strength. Different saturation levels selectively precipitate protein classes based on surface hydrophobicity and charge distribution.
  • Common in enzyme purification workflows to concentrate and stabilize labile proteins prior to chromatography.
• Precipitation and stabilization:
  • Concentration of immunoglobulins and other serum proteins; stabilization of protein structure by preferential exclusion of sulfate ions from hydration shells.
• Phase behavior and extraction:
  • Creation of aqueous two-phase systems (e.g., polymer/salt ATPS) for biomolecule partitioning.
  • Salting-out extraction of small organics from water by adding ammonium sulfate to drive phase separation with water-miscible organics (e.g., acetonitrile), improving recoveries and GC sample prep.
• Reaction media effects:
  • Control of ionic strength and activity coefficients in enzymatic assays; modulation of enzyme kinetics, often reducing protease activity.
• Synthetic contexts:
  • Source of ammonium for ion-exchange equilibration and precipitation of metal sulfates; occasionally used to adjust crystallization conditions in materials and coordination chemistry.

Practical tips (literature):

• Prepare fresh solutions; filter to remove dust/insolubles for sensitive applications.
• Use accurate solubility tables to set saturation levels; temperature affects solubility and precipitation boundaries.
• Dialysis or diafiltration is typically required post-precipitation to remove excess salt before downstream steps.

Reaction Conditions

General laboratory conditions for common uses (literature; indicative only—optimize per system):

• Protein precipitation (ammonium sulfate cut):

  • Medium: Aqueous buffered protein solution (e.g., phosphate, Tris) kept at 0–10 °C to favor stability.
  • Addition: Incremental addition of solid or concentrated stock with vigorous stirring to reach a target % saturation; equilibration times typically 15–60 min per step.
  • Isolation: Centrifugation at 4–10 °C; pellets redissolved in appropriate buffer; excess salt removed by dialysis or ultrafiltration.

• Salting-out extraction (SOE):

  • Medium: Aqueous sample with added ammonium sulfate to near-saturation; extractant such as acetonitrile or methyl tert-butyl ether added to induce phase split.
  • Temperature: Ambient; ensure complete dissolution of salt before phase contact.
  • Notes: Validate partitioning of analytes; monitor water content in organic phase.

• ATPS (polymer/salt):

  • Components: PEG or similar polymer + ammonium sulfate + water; compositions selected from phase diagrams to position within two-phase region.
  • Temperature: Ambient to chilled; gentle mixing followed by phase settling.

• Materials/metal precipitation:

  • pH control is critical; addition of ammonium sulfate can precipitate certain metal sulfates; confirm solubility products and avoid co-precipitation of unwanted species.

Always verify solubility curves and temperature dependence from authoritative tables; protein-specific behavior varies widely and demands empirical optimization.

Safety and Handling

Safety information specific to this catalog item (GHS, H-statements, pictograms): Not specified for this item; refer to SDS.

General safety profile for ammonium sulfate (literature; consult SDS for authoritative guidance):

• Classification: Often not classified as hazardous under GHS for laboratory use; may cause eye/skin irritation and respiratory tract irritation as a nuisance dust.
• Decomposition hazards: On strong heating, decomposes to ammonia, sulfur dioxide, and sulfur trioxide; avoid heating in confined spaces.
• Incompatibilities: Strong bases (release of ammonia), strong oxidizers, and nitrates at elevated temperatures. Avoid mixing with alkaline materials in damp conditions to limit ammonia evolution.
• PPE: Laboratory coat, safety glasses or goggles, and appropriate gloves (e.g., nitrile). Use dust control measures and avoid inhalation of particulates.
• Engineering controls: Handle powders in a fume hood or with local exhaust ventilation; minimize dust generation.
• First aid (overview):
  • Inhalation: Move to fresh air; seek medical attention if irritation persists.
  • Skin/Eye contact: Rinse with water for several minutes; remove contaminated clothing; obtain medical attention for persistent irritation.
  • Ingestion: Rinse mouth; do not induce vomiting; seek medical advice if unwell.
• Environmental considerations: Solutions can contribute to eutrophication; prevent uncontrolled discharge to waterways.

Always consult the product’s SDS for definitive hazard classification, exposure limits, and emergency procedures for your jurisdiction.

Solvent Selection

This product is a solid inorganic salt; “solvent selection” pertains to its dissolution and use environment rather than choosing it as a solvent.

• Polarity and miscibility (literature):

  • Highly water-soluble; effectively insoluble in common organic solvents (alcohols, ketones, ethers, hydrocarbons).
  • Aqueous solutions display high ionic strength and promote salting-out of proteins and some organics.

• Practical dissolution guidance:

  • Use deionized water; dissolution is endothermic—mild warming (room temperature to ~37 °C) and vigorous stirring accelerate dissolution.
  • Add solid gradually to avoid local supersaturation and caking. Prepare concentrated stocks or saturated solutions as required by protocol.

• When to choose ammonium sulfate vs. alternatives:

  • Use ammonium sulfate when you need strong, controllable ionic strength for protein precipitation or to modulate phase behavior in aqueous two-phase systems.
  • Prefer volatile ammonium salts (e.g., ammonium acetate or bicarbonate) when downstream drying, lyophilization, or MS compatibility is critical.
  • For generic ionic strength adjustment without ammonium, sodium/potassium sulfate or chloride may be used, but they do not confer the same buffering behavior of NH4+/NH3.

• Small comparison (literature):

  • Ammonium sulfate: very high ionic strength, strong salting-out, non-volatile, low UV background.
  • Ammonium acetate: moderate ionic strength, volatile, MS-friendly, weaker salting-out.

Storage and Reconstitution

• Storage conditions (per Product Data): Room temperature, Desiccated, Cool. Shipments: Normal.

  • Keep container tightly closed in a dry environment to prevent caking from moisture uptake.
  • Avoid prolonged exposure to humidity; use desiccant packs where appropriate.

• Stability (general literature):

  • Chemically stable as a solid for extended periods when dry. Aqueous solutions are stable but can support microbial growth; prepare fresh or filter-sterilize and store cold if required by your application.

• Reconstitution and solution preparation:

  • Dissolves readily in deionized water; dissolution is endothermic—use stirring and mild warming to accelerate.
  • For sensitive biochemical work, prepare solutions with high-purity water, then clarify/sterile-filter (e.g., 0.22 µm) to remove particulates/bioburden.
  • Avoid strong bases during dissolution to prevent ammonia evolution; set pH with compatible buffers rather than concentrated alkali.

• Specifications not provided for this item:

  • Water content/moisture, insolubles, bioburden/endotoxin, UV cutoff. Not specified for this item; refer to CoA/Spec Sheet.

Always follow your lab’s quality system and consult the SDS for safe handling during storage and solution preparation.

Structure and Identity

Ammonium sulfate is an inorganic salt comprising two ammonium cations and one sulfate dianion.

• Product Data identifiers:
  • CAS: 7783-20-2
  • CID: 6097028
  • InChIKey (as provided): 23496
  • SMILES (as provided): Not specified for this item; refer to CoA/Spec Sheet.
• Literature/typical identifiers (for reference):
  • Molecular formula: (NH4)2SO4 (literature)
  • Molecular weight: 132.14 g/mol (literature)
  • Canonical SMILES: [NH4+].[NH4+].O=S([O-])(=O)[O-] (literature)
• Structural features (general chemistry description):
  • Contains two ammonium (NH4+) ions electrostatically paired with one sulfate (SO4 2−) tetrahedral anion.
  • The sulfate center is a tetrahedral sulfur(VI) atom double-bonded to two oxygens and single-bonded to two anionic oxygens; no stereogenic centers.
  • In the solid state, forms an extended ionic lattice; in water, fully dissociates to NH4+ and SO4 2−.
• 2D description in words:
  • A central SO4 unit with S=O bonds to two oxygens and S–O− bonds to two negatively charged oxygens. Two discrete, spherical NH4+ cations associate with the two O− sites through ionic interactions and hydrogen bonding in the crystal lattice.

Synthetic Utility

Although not a classical organic reagent, ammonium sulfate offers practical utility across synthetic and analytical workflows (literature):

• Salting-out extraction (SOE): Addition to aqueous matrices reduces the solubility of organics and promotes phase separation with water-miscible solvents (e.g., acetonitrile), improving recovery for GC/LC sample preparation.
• Crystallization control: Ionic strength and kosmotropic effects can modulate crystallization kinetics of inorganic complexes and some organic salts, aiding purification.
• Precursor/ion source: Provides ammonium for ion-exchange equilibration and sulfate for precipitating metal sulfates under controlled pH; useful in materials chemistry and coordination complexes preparation.
• Aqueous two-phase systems (ATPS): Serves as the salt component (polymer/salt) to partition biomolecules and certain nanoparticles.
• Analytical chemistry: Employed to adjust ionic strength in electrophoresis and capillary methods to influence migration and reduce electroosmotic flow, when compatible with detection.

Strategic value:

• Non-volatile, inexpensive, and high solubility enable robust control of ionic environments. However, its persistence demands post-process desalting when purity or volatility is required. For workflows culminating in MS or drying, plan a switch to volatile ammonium salts after the high-salt operations.

Target Specificity

Not applicable. This product is an inorganic salt, not a biological targeting reagent or antibody. No antigen, epitope, clone, isotype, or species reactivity applies. For application-relevant details, see Reaction & Applications and Synthetic Utility.

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.

What does UltraBio? mean?

UltraBio? indicates that the product has been processed and tested for biological and biochemical applications. Specifications may include endotoxin limits, microbial controls, sterility, low DNase/RNase/protease activity, and verified biological activity where relevant.

What does Ultra pure mean?

Ultra pure is a defined analytical purity tier suitable for general analytical and reagent applications. It specifies a minimum assay percentage, controlled limits on common impurities (water, heavy metals, residue on ignition), and lot-to-lot consistency. Ultra pure is one of several purity tiers — choose based on the sensitivity and regulatory requirements of your method.

How should this product be stored?

Store in a cool place, desiccated. Keep the container tightly closed with desiccant — the material is moisture-sensitive.

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.