Ammonium fluoride - UPSS grade,Single metal impurity ≤ 0.1ppb, 40wt.% in H2O , CAS No.12125-01-8

CAS: 12125-01-8 Cat. No.: A1524030 Formula: H₄FN Molecular Weight: 37.04 EC Number: 235-185-9 PubChem CID: 25516

GRADE & PURITY UPSS grade, Single metal impurity ≤ 0.1ppb, 40wt.% in H2O

Storage

Room temperature

Shipped In

Normal

Specifications

Specifications & Purity

UPSS grade,Single metal impurity ≤ 0.1ppb, 40wt.% in H2O

Storage

Room temperature

Shipped In

Normal

Grade

UPSS grade

Names and Identifiers

Isomeric SMILES

[NH4+].[F-]

WGK Germany

1

RTECS

BQ6300000

PubChem CID

25516

UN Number

2505

Packing Group

III

Molecular Weight

37.04

Chemical and Physical Properties

• Solubility: Soluble in cold water, slightly soluble in alcohol, insoluble in ammonia

Application Protocols

No item-specific, validated application protocols are provided in the Product Data.

General guidance (literature/practice) for two common laboratory uses:

• Desilylation setup:

  • Dissolve substrate in MeOH or MeOH/H2O.
  • Add NH4F (solid or concentrated aqueous solution) to achieve 3–10 equiv.
  • Stir at 20–60 °C; monitor progress by TLC/GC/LC–MS.
  • Quench and work up as described under Reaction Conditions; manage fluoride waste via CaF2 precipitation.

• Oxide surface preparation (conceptual):

  • Prepare aqueous NH4F solution in plasticware with DI water.
  • If HF buffering is required (BOE), follow institutional SOPs for HF work; use appropriate PPE and engineering controls.

Because real-world outcomes depend on substrate, matrix, and equipment, users should validate and document their own SOPs. For research use only.

Biological Roles

This section provides general biochemical context; it does not imply suitability for biological or clinical use.

• Ions and equilibria (literature/general):

  • Ammonium (NH4+) is a conjugate acid of ammonia and participates in nitrogen metabolism and acid–base homeostasis in living systems. However, elevated ammonium is toxic to cells and organisms.
  • Fluoride (F−) is a potent enzyme inhibitor; classic targets include glycolytic enolase, where fluoride complexes Mg2+ at the active site, reducing enzymatic turnover. Fluoride also interacts with H-bond networks and can affect proton transport.

• Cellular effects:

  • At millimolar concentrations, fluoride can alter phosphorylation cascades (e.g., via aluminum fluoride complexes that mimic phosphate), and inhibit various metalloenzymes.
  • Ammonium salts can acidify compartments and influence membrane potentials through NH3/NH4+ diffusion equilibria.

• Practical implications for lab work:

  • NH4F solutions are generally incompatible with most live-cell systems due to fluoride toxicity; any biological application should be strictly in vitro and well-controlled.
  • In protein/enzymology experiments, fluoride is sometimes used as a mechanistic probe or to suppress metalloprotease activity, but concentrations and exposure times must be carefully optimized to avoid non-specific effects.

No item-specific biological validation, purity for bio-use, or endotoxin levels are provided in the Product Data; confirm suitability with your internal QC as needed.

Buffer Applications

Ammonium fluoride is not a conventional biological buffer. However, it participates in two buffer-related contexts (literature/general):

• Buffered oxide etch (BOE):

  • NH4F combined with HF forms a chemical buffer that moderates free HF activity, enabling controlled etching of SiO2 in microfabrication. Multiple formulations (e.g., 6:1 or 7:1 NH4F:HF volume ratios) are used in the semiconductor industry. Due to HF hazards, recipe preparation, handling, and waste treatment must follow institutional protocols; do not attempt without specialized facilities.

• Ammonium/ammonia buffering:

  • In water, NH4+ and NH3 constitute a buffer around pH ~9.25 (pKa of NH4+), but the presence of fluoride (a weak base conjugate to HF) alters solution pH via competing equilibria. As a stand-alone buffer for biochemical assays, NH4F is uncommon and generally not recommended due to enzyme inhibition by fluoride and potential glass etching.

Practical guidance:

• For biological pH control, prefer established buffers (HEPES, Tris, phosphate) with well-characterized ionic strength and minimal side reactivity.
• For oxide etching, use dedicated BOE solutions prepared in plasticware, verify concentration by titration or conductivity if required, and label clearly with HF warnings.

Green Alternatives

Selecting a fluoride source involves tradeoffs among hazard, solvent, and waste. General, literature-based comparison:

• Hazard and exposure:

  • NH4F avoids direct handling of anhydrous HF but can generate HF with acids; still requires strong controls. Fluoride waste must be complexed (e.g., with Ca2+) before disposal per regulations.
  • Organic fluorides like TBAF pose different toxicity and persistence concerns; some formulations contain residual HF or water.

• Solvent and process:

  • NH4F is effective in aqueous/alcoholic media, enabling water-based processing and potentially lowering VOCs.
  • KF/CsF in green solvents (e.g., PEGs, glycerol, water/ethanol) can sometimes substitute for NH4F, offering lower volatility and simpler waste profiles.

• Equipment and compatibility:

  • Aqueous NH4F systems can attack glass; plastics are preferred. KF/CsF are less aggressive to glass in neutral media but still can etch silica under certain conditions.

Illustrative comparison (literature/general):

• NH4F (H2O/MeOH):
  • Pros: Water-compatible; controllable fluoride delivery; useful in oxide processing.
  • Cons: HF liberation risk with acids; glass etching; fluoride toxicity.
• KF (H2O/EtOH or PEG):
  • Pros: Lower volatility; benign counterion; broad availability.
  • Cons: Lower solubility; may require phase-transfer catalysts for organic media.
• TBAF (THF/MeOH):
  • Pros: Strong fluoride donor in aprotic media; efficient desilylation.
  • Cons: Moisture sensitivity; organic cation persistence; different EHS profile.

Green-by-design tips:

• Use minimal fluoride charge consistent with target performance.
• Prefer aqueous/alcoholic systems and closed equipment.
• Implement fluoride capture/neutralization (e.g., CaF2 precipitation) at point of generation.

Pharmaceutical Uses

No item-specific pharmacopeial status or excipient role is provided in the Product Data.

General considerations (literature/industry knowledge):

• Ammonium fluoride is not a common pharmaceutical excipient due to fluoride toxicity and potential reactivity. Its use in drug product formulation is rare to nonexistent.
• In pharmaceutical manufacturing or analytical contexts, fluoride salts may occasionally be used for etching/cleaning of silica-containing components, or as reagents in synthetic steps for intermediates, but such uses are confined to controlled plant or lab environments with appropriate waste management.
• Regulatory aspects: If contemplated for any GMP-relevant application (e.g., as a process reagent), full qualification of grade, impurity profile (especially metals and other halides), and residual limits in the final product must be established. No such specifications are provided here; consult the CoA and your QA unit.

Conclusion: For research and process development only. Do not use for human or veterinary applications. For any contact with manufacturing assets, ensure compatibility testing (e.g., elastomers, glass, stainless steels) and confirm that fluoride-containing effluents are properly neutralized and disposed of.

Physical Properties

Item-specific numeric specifications (e.g., exact assay, trace metals, water, peroxide, UV cutoff) are not provided. Use the CoA/Spec Sheet for authoritative values.

Literature/general properties for anhydrous ammonium fluoride (for planning only):

• Physical state/appearance: White, hygroscopic crystalline solid (literature)
• Melting point: ~100 °C (some decomposition; literature)
• Boiling point: Not applicable; decomposes/sublimes before boiling (literature)
• Density: ~1.01 g/cm³ at 25 °C (literature)
• Solubility:
  • Water: Freely soluble; highly dissociated to NH4+ and F− (literature)
  • Alcohols: Soluble in methanol and ethanol to useful concentrations (literature)
  • Aprotic/nonpolar solvents (e.g., ethers, hydrocarbons): Essentially insoluble (literature)
• pKa/pKb context (literature): NH4+/NH3 conjugate acid pKa ≈ 9.25; HF/F− conjugate acid pKa ≈ 3.2. Solutions of NH4F are typically near-neutral to slightly acidic/basic depending on concentration and dissolved CO2.
• Hygroscopicity: Picks up moisture; solutions can slowly attack glass (literature)
• Odor: Odorless to faint ammonia note when traces of NH3 are present (literature)

Practical notes (general):

• Strong hydration of F− leads to endothermic dissolution; stir to avoid localized cooling.
• Avoid heating above its melting point; thermal decomposition can release ammonia and HF-containing vapors.

All numeric data above are typical literature values and not product specifications.

Quality & Grades

• Item-specific grade: UPSS grade (as listed). The precise definition/specification envelope for UPSS grade is not provided in the Product Data.
  • Implication: Without a published, external standard (e.g., ACS, USP, EP) explicitly stated, users should consult the product’s CoA/Spec Sheet for assay, impurity limits (e.g., heavy metals), particle size, water content, and any stabilizers.

General guidance on grade context (literature/market knowledge):

• Inorganic salts for materials science often emphasize low particulate and low trace-metal profiles when used in microfabrication or catalysis research. If such attributes are critical, verify with the CoA.
• Chromatography- or electronics-oriented grades may also specify low non-volatile residue and defined conductivity in solution. Again, confirm item-specific details on the CoA.

Recommendations for this item:

• Request current CoA for your lot to confirm:
  • Assay (%), loss on drying, and trace metal content.
  • Insoluble matter and pH of a defined aqueous solution.
  • Bioburden/endotoxin if relevant to your process (rare for this salt, but occasionally requested in sensitive environments).
• If process-critical, perform incoming QC (ion chromatography for anions/cations; ICP-MS for metals; Karl Fischer for moisture if applicable).

Note: No stabilizers or additives are indicated in the Product Data; if present, they will be listed on the CoA.

Reaction & Applications

Ammonium fluoride serves as a convenient, water-compatible fluoride source and a component in materials processing. Key uses (literature/general):

• Surface treatment and microfabrication:

  • Component of buffered oxide etch (BOE) with HF to etch SiO2 and silicate glasses; NH4+ moderates free HF via complexation, improving rate control. Use only with appropriate HF safety infrastructure.
  • Cleaning/activation of silica, glass, and metal oxides; can remove native Si–O layers prior to deposition steps.

• Organic synthesis:

  • Desilylation (Si–O/Si–C cleavage): NH4F in MeOH/H2O can remove silyl protecting groups (e.g., TMS ethers) under relatively mild, protic conditions; rates increase with temperature and water content. Substrate-dependent selectivity; tertiary silyl groups often require stronger fluoride donors or higher temperature.
  • Silicon-mediated transformations: Fluoride activation of hypervalent silicon intermediates (e.g., Tamao–Fleming type sequences) often uses more lipophilic fluorides; however, NH4F can be employed in biphasic/protic setups when substrates tolerate water/alcohol.
  • Mineralizer in zeolite/materials syntheses: Fluoride media can template framework formation and reduce defect density.

• Analytical/sample prep:

  • Aids dissolution of silica-containing matrices for analysis (with caution regarding glassware and HF formation with acids).

Practical tips:

• Use plastic spatulas/containers; avoid glass for storage of concentrated solutions.
• Control pH and temperature; acidic conditions can generate HF in situ.
• For desilylation, start with 3–10 equiv NH4F in MeOH or MeOH/H2O at 20–60 °C; monitor by TLC/GC/MS. Adjust solvent and temperature per substrate.

All procedures should be validated and executed under appropriate safety controls.

Reaction Conditions

The following are literature/general guidelines for common applications; they are not product specifications.

• Desilylation of TMS ethers:

  • Solvent: MeOH, MeOH/H2O (up to 1:1), or EtOH. Plastic vessels or PTFE-lined reactors preferred for concentrated solutions.
  • Reagent charge: 3–10 equiv NH4F relative to silyl groups; increase for more hindered silyl ethers.
  • Temperature: 20–60 °C; typical reactions complete within 0.5–6 h depending on substrate/equivalents.
  • Workup: Dilute with water, extract with suitable organic solvent; neutralize fluoride-containing aqueous waste with CaCl2/Ca(OH)2 to precipitate CaF2.

• Surface/oxide processing (BOE conceptually):

  • Composition: Aqueous NH4F with defined HF addition to buffer free HF activity (handled only in specialized facilities).
  • Temperature: Typically ambient; rate increases with temperature but at the cost of safety and selectivity.
  • Materials: Use HDPE/PP/PTFE tanks, tools, and tubing. Glass and many metals are incompatible.

• Materials synthesis/mineralization (zeolites/sol–gel):

  • Media: H2O or alcohol/water mixtures; pH controlled to avoid HF formation unless explicitly required.
  • Temperatures: Ambient to 120 °C (sealed systems) depending on formulation; consult specific literature protocols.

• Compatibility and monitoring:

  • Avoid acids; maintain neutral to slightly basic conditions when HF is not desired.
  • Monitor by TLC/GC/LC as appropriate; fluoride can interfere with some silica-based chromatography; condition columns appropriately and consider alumina when feasible.

Always conduct hazard assessments and small-scale trials before scale-up.

Safety & Handling

Item-specific GHS fields in Product Data are not provided. Always consult the product SDS for authoritative hazard classification, pictograms, and first-aid.

General/literature safety considerations for ammonium fluoride:

• Hazards (general): Fluoride salts are toxic if swallowed or upon significant skin/eye exposure. Contact with acids liberates hydrogen fluoride (HF), a highly corrosive, systemic toxin. Thermal decomposition can release ammonia and HF-containing fumes.
• PPE: Use chemical-resistant gloves (e.g., nitrile; change regularly), lab coat, splash goggles or face shield. Employ a fume hood when weighing, transferring, or preparing solutions, especially if acids may be present.
• Incompatibilities: Acids (HF release), strong oxidizers (general caution), and bases that may shift equilibria to ammonia release. Concentrated aqueous fluoride can etch/scratch glass; prefer plastic (HDPE, PP, PTFE) for storage and handling.
• Storage: Keep tightly closed at room temperature (item-specific), in a dry place. Use secondary containment; store away from acids. Minimize ambient moisture uptake.
• First aid (overview; defer to SDS):
  • Skin/eye contact: Immediate irrigation with copious water for ≥15 min; urgent medical evaluation. Calcium gluconate gel is commonly cited for fluoride skin exposures (per institutional protocols).
  • Inhalation: Move to fresh air; medical evaluation if symptoms develop.
  • Ingestion: Rinse mouth; do not induce vomiting; seek medical care.
• Spill/cleanup: Avoid dust; collect with minimal water into plastic containers. Neutralize/complex fluoride with calcium salts per institutional guidance.

Always refer to the current SDS and institutional EHS procedures for detailed guidance.

Solvent Selection

As an ionic inorganic salt, ammonium fluoride is a reagent/solute rather than a solvent. Solvent choice should maximize solubility, control reactivity of fluoride, and protect equipment.

• Polarity and solvation (literature/general):

  • Highly soluble in polar protic solvents, especially water, methanol, and ethanol, where strong hydrogen bonding stabilizes F− and NH4+.
  • Poorly soluble to insoluble in aprotic, low-dielectric media (ethers, hydrocarbons, chlorinated solvents).

• Typical solvent systems by application:

  • Aqueous processing/etching: Deionized water is standard. For silicon oxide etching, NH4F is commonly combined with HF to form buffered oxide etch (BOE); use only with appropriate facilities and plastics.
  • Organic synthesis/desilylation: MeOH or EtOH often used; NH4F can activate Si–O cleavage in protic media. Water/MeOH blends balance rate and substrate compatibility.
  • Fluoride delivery to phase-separated systems: Consider phase-transfer strategies or switch to more soluble fluoride sources (e.g., TBAF) if nonprotic solvents are mandatory.

• Compatibility notes:

  • Avoid long contact with glassware for concentrated or hot solutions; prefer PTFE, PP, or HDPE reactors and storage.
  • Control water content: hydration state of fluoride affects nucleophilicity and selectivity.

Brief comparison (literature/general):

• NH4F in H2O/MeOH: safer than HF alone; moderate basicity; good for silica interactions.
• TBAF in THF/DMF: higher nucleophilicity in aprotic media but more moisture sensitive and different safety profile.

Select solvent to balance solubility, substrate stability, and equipment compatibility.

Storage & Reconstitution

• Storage (item-specific): Room temperature, tightly closed. Shipped under normal conditions per Product Data.
• Container/materials: Use plastic (HDPE/PP/PTFE) containers; avoid prolonged storage of concentrated solutions in glass due to potential etching.
• Moisture control: Hygroscopic; store in a dry area. Reseal promptly after use. If clumping occurs from moisture uptake, gently break up under dry conditions; do not heat aggressively (risk of decomposition).

Reconstitution/preparation of solutions (general):

• Solvent: Deionized water is typical; methanol or ethanol can be used for organic-compatible applications.
• Concentration: Prepare only what is needed; common lab stocks range from 0.1–4 M in water depending on use (literature/general; set according to your process and safety limits).
• Technique: Add solid NH4F slowly to solvent with stirring; dissolution is endothermic. Prepare in plasticware. Avoid acids; do not mix with glass etchants unless under approved SOPs.
• Filtration: If particulate control is required, filter through fluoride-compatible membranes (PTFE, PVDF). Avoid cellulose nitrate for strong fluoride solutions.
• Stability: Aqueous solutions are generally stable for days to weeks when clean and closed; monitor pH and clarity. Discard if contamination, precipitation, or significant pH drift is observed.

Waste: Treat fluoride-containing solutions with calcium salts to precipitate CaF2 before disposal, following institutional and regulatory requirements.

For any exact solution specifications (e.g., conductivity, pH), consult the CoA/Spec Sheet for this item or perform in-house QC.

Structure & Identity

Ammonium fluoride is an inorganic, ionic fluoride salt composed of a tetrahedral ammonium cation and a fluoride anion.

• Item-specific identifiers (from Product Data):

  • SKU: A1524030
  • CAS: 12125-01-8
  • Category: Materials Science (research use only)
  • Grade: UPSS grade
  • Storage (item-specific): Room temperature
  • Shipping (item-specific): Normal
  • SMILES: Not specified for this item; refer to CoA/Spec Sheet.
  • InChIKey: Not specified for this item; refer to CoA/Spec Sheet.

• Core chemical identity (literature/general):

  • Preferred name: Ammonium fluoride
  • Molecular formula: NH4F (literature)
  • Molecular weight: ~37.04 g/mol (literature)
  • SMILES (ionic): [NH4+].[F-] (literature)

• Structural features (descriptive):

  • Contains a tetrahedral ammonium cation (NH4+) engaged in extensive hydrogen bonding in the crystal lattice.
  • Fluoride anion (F−) is a hard base with strong hydrogen-bond accepting ability.
  • No stereocenters; 2D depiction shows a separated cation [NH4+] and anion [F−].

• Synonyms (literature/general): ammonium fluoride (anhydrous); ammonia fluoride; ammonium monofluoride.

Note: Where specific identifiers are required for regulatory or analytical purposes, consult the product CoA/Spec Sheet for item-specific confirmation.

Synthetic Utility

Ammonium fluoride delivers fluoride in protic media and engages strongly with silicon and many metal oxides. Literature/general uses include:

• Fluoride-mediated deprotections:

  • Desilylation of trimethylsilyl (TMS) ethers and some aryl/alkenyl silyl groups in MeOH/H2O or EtOH, providing a practical alternative to TBAF when aprotic conditions are not required. Benzylic/allylic silyl ethers typically react faster; bulky silyl groups (TBDMS/TIPS) may need higher temperature or stronger fluoride.

• Activation of Si-based intermediates:

  • Fluoride initiates formation of hypervalent siliconates, enabling downstream transformations (e.g., migration/oxidation sequences). NH4F is suitable when substrates tolerate water/alcohol.

• Mineralizer/template in materials synthesis:

  • In sol–gel and zeolite preparations, F− can reduce defect density and influence morphology. NH4+ introduces volatility upon calcination, simplifying removal of the counterion.

• Inorganic/analytical chemistry:

  • Promotes dissolution of siliceous matrices and modifies surface hydroxyl densities on oxides prior to functionalization.

Strategic advantages:

• Water/alcohol compatibility; simple workup by aqueous partition and precipitation of fluoride as CaF2 during quench/waste treatment.
• Avoids lipophilic ammonium residues associated with quaternary ammonium fluorides.

Caveats:

• Acidic conditions generate HF; rigorously segregate acids.
• Limited solubility in aprotic organic solvents restricts its use without co-solvents or phase-transfer methods.

Always verify substrate compatibility and optimize equivalents, temperature, and solvent composition on small scale first.

Target Specificity

Not applicable. This product is an inorganic salt reagent, not a biological affinity reagent or antibody. No antigen/epitope, clone, isotype, or species reactivity information applies.