(±)11-HETE-d , CAS No.2750534-80-4

CAS: 2750534-80-4 Cat. No.: H1447603 Fórmula: C₂₀H₂₄D₈O₃ Peso molecular: 328.52

Storage

Store at -20°C

Shipped In

Ice chest + Ice pads

Visão geral

(±)11-HETE-d 8 is the deuterium labeled (±)11-HETE.

Specifications

Condições de armazenamento de armazenamento

Store at -20°C

Enviado em

Ice chest + Ice pads

Este produto requer transporte de cadeia fria. Serviços terrestres e outros serviços econômicos não estão disponíveis.

Nomes e identificadores

• Peso molecular: 328.52

Application Protocols

The following are general, literature-based protocols for using deuterated eicosanoid standards in LC‑MS/MS. Adjust to your instrument and validated SOPs. These are not product-specific instructions.

A. Stock and working solution preparation

• Allow vial to equilibrate to room temperature while protected from light. Briefly centrifuge to collect contents.
• Prepare a primary stock (e.g., 1–10 mg/mL) in ethanol, methanol, acetonitrile, or DMSO. Mix gently; avoid vigorous vortexing that entrains air.
• Aliquot into amber, low‑adsorption vials; backfill headspace with N2/Ar; store at −20 °C.
• Prepare intermediate and working solutions in MeOH or 50:50 MeOH:water with 0.1% acetic/formic acid as needed for spiking and calibration.

B. Sample preparation for plasma/serum (example)

• Spike a fixed volume of internal standard working solution into each sample, calibrator, and QC prior to protein precipitation or extraction.
• Precipitate proteins with 3–4 volumes of cold ACN or MeOH; vortex and centrifuge. Alternatively, apply to SPE (C18 or mixed‑mode) conditioned with MeOH and water; wash and elute with MeOH or MeOH:EtOAc.
• Evaporate solvent under N2 at room temp or ≤30 °C; reconstitute in initial LC mobile phase.

C. LC‑MS/MS settings (typical)

• Chromatography: C18, water/MeOH gradient with 0.01–0.1% acid. Column temp 35–45 °C.
• Ionization: ESI negative mode. Optimize source parameters (capillary voltage, gas flows, temperature) for your instrument.
• Transitions: Select MRM transitions appropriate for your deuterated analog per CoA/method; verify fragmentation and retention.

Quality controls

• Include system suitability, blanks, zero calibrators, and QCs (low/mid/high). Monitor recovery, matrix effects, and stability (bench‑top, autosampler, freeze–thaw).

Biological Roles

Context (general/literature; no medical claims):

• 11‑HETE (11‑hydroxyeicosatetraenoic acid) is a monohydroxylated metabolite of arachidonic acid produced via oxidative pathways, including cytochrome P450 epoxidation/hydroxylation and non‑enzymatic peroxidation followed by reduction. Multiple positional and stereochemical isomers can arise depending on the pathway.
• As an eicosanoid, 11‑HETE belongs to a class of lipid mediators that modulate cellular signaling. It can influence pathways associated with inflammation biology, vascular tone, and cell signaling cascades in vitro, although specific receptor interactions and downstream effects vary by isomer and context.
• Cellular handling: 11‑HETE is bound and transported by albumin and intracellular fatty acid‑binding proteins; it may be further conjugated (e.g., to CoA derivatives) or esterified into phospholipids/neutral lipids.
• Turnover: It can be oxidized at the alcohol to form corresponding oxo‑eicosatetraenoic acids (11‑KETE) or undergo β‑oxidation and ω‑oxidation. Enzymatic reduction/oxidation steps are compartmentalized across cytosol, peroxisomes, and mitochondria.
• Analytical significance: Due to potential isomeric complexity and low endogenous levels, stable isotope‑labeled internal standards like 11‑HETE‑d are essential for reliable quantification in complex matrices by LC‑MS/MS, enabling correction for recovery and ionization variability.

Note: The biological roles summarized above describe endogenous 11‑HETE. The deuterated compound serves as a tracer/internal standard and is not intended for biological effects studies. All uses are for research only.

Buffer Applications

This compound is a hydrophobic, weakly acidic lipid and is not used as a buffering agent. It lacks a conjugate acid–base pair suitable for maintaining pH over a defined range.

Practical guidance:

• When incorporating into aqueous buffers for assays, dissolve first in a miscible organic solvent (e.g., ethanol, methanol, or DMSO) and add to buffer with vigorous mixing to prevent precipitation. Maintain sufficient co‑solvent (often 0.1–1% v/v for working solutions; method-dependent) to ensure solubility.
• For high aqueous content systems, consider forming the sodium or potassium salt transiently or using carrier proteins (e.g., BSA) and surfactant systems consistent with your protocol, recognizing potential impacts on recovery and ionization in LC‑MS.

For buffer recipes, pH ranges, and ionic strength guidance, refer instead to standard biological buffers (e.g., phosphate, HEPES, Tris), as they are applicable to the assay environment rather than this analyte.

Green Alternatives

Although (±)11‑HETE‑d is a specialty analyte rather than a process solvent or bulk reagent, greener choices can be made around its use.

Greener handling choices (general):

• Solvent selection:
  • Prefer ethanol or methanol for stock/working solutions where compatible with your LC‑MS method, instead of halogenated solvents (CH2Cl2, CHCl3).
  • Use acetonitrile or methanol for protein precipitation and SPE rather than more hazardous ethers.
• Miniaturization:
  • Employ microextraction and microsampling approaches (SPE µcartridges, SPME) to reduce solvent consumption.
• Waste reduction:
  • Pool calibrators across analyte panels to minimize duplicate preparations.
  • Use multi-well plate SPE to decrease per‑sample solvent volumes.

Comparison (general considerations):

• Ethanol vs Dichloromethane for dissolution
  • Safety/Environment: EtOH is low toxicity/biodegradable; CH2Cl2 is volatile, toxic, and a suspected carcinogen.
  • Performance: EtOH adequately dissolves 11‑HETE derivatives for most analytical uses; CH2Cl2 offers rapid drying and high solubility but is seldom necessary.
• MTBE vs Hexane in LLE for lipids
  • Safety: MTBE has lower neurotoxicity concerns than hexane; both are VOCs—capture vapors appropriately.
  • Performance: MTBE provides efficient phase separation with aqueous buffers and good recovery for eicosanoids.

Sourcing and lifecycle:

• Order quantities aligned with short‑term study needs to limit degradation/waste.
• Store in durable, light‑protective containers to extend shelf life and reduce re‑orders and shipping frequency.

Pharmaceutical Uses

No therapeutic/clinical uses are claimed. For research use only.

Relevant roles in pharmaceutical R&D and QC (general/literature):

• Analytical reference standard: Deuterated 11‑HETE is used in bioanalytical method development and validation (LC‑MS/MS) to quantify endogenous 11‑HETE in preclinical and clinical study samples. It supports calibration curve construction, internal standardization, and stability assessments under method validation guidelines (e.g., FDA/EMA bioanalytical guidance).
• Process and formulation studies: May be used to study lipid mediator stability in biological matrices, evaluate extraction recoveries, and assess matrix effects during sample preparation approaches (protein precipitation, SPE, LLE).
• System suitability: Employed as a system suitability/internal standard to monitor LC‑MS performance (retention time stability, ion ratio consistency, detector sensitivity) during analytical runs.
• Cross‑platform harmonization: Provides a common internal standard for interlaboratory comparison and proficiency testing in lipidomics panels.

Documentation needs:

• For regulated bioanalysis, ensure traceable CoA specifying chemical purity, isotopic enrichment, and isomeric composition; retain shipping/stability records and storage logs (−20 °C) to support data integrity.

Note: This section describes roles as an analytical standard/excipient in R&D and QC contexts only; no claims are made regarding therapeutic application or clinical efficacy.

Physical Properties

Item-specific values (this product):

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Grade/Purity: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.

General/literature physical properties for 11‑HETE and deuterated analogs (for context; not product specifications):

• Physical state: Typically a viscous oil or low‑melting waxy solid at room temperature; tends to form films upon drying.
• Solubility: Sparingly soluble in water (free acid). Readily soluble in polar organic solvents (ethanol, methanol, acetonitrile, isopropanol) and in aprotic solvents (DMSO, DMF). Soluble in nonpolar/medium polarity solvents (chloroform, dichloromethane, ethyl acetate, hexane) as the neutral acid; solubility improved by conversion to salts (e.g., Na+).
• Partitioning: Highly lipophilic due to C20 chain and multiple C=C bonds; expected high logP (literature, qualitative).
• Acid/base: Carboxylic acid pKa typically ~4.5–5 for long-chain fatty acids (literature typical range; actual pKa influenced by solvent and microenvironment). Hydroxyl at C11 is weakly acidic (alcoholic OH).
• UV/Vis: Conjugated polyunsaturation provides absorbance in the UV; λmax and cutoff vary with geometry/solvent (literature guidance only). For quantitative work, LC‑MS/MS with SRM/MRM is preferred over UV due to specificity.
• Stability: Susceptible to autoxidation and isomerization under light/air, especially in solution. Deuteration can modestly influence kinetic stability at labeled positions but does not eliminate oxidation risk.

Handling note: For exact density, refractive index, melting/boiling points, and specific solubility for this lot, consult the CoA/Spec Sheet.

Quality and Grades

Item-specific quality information:

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

Interpretation and typical expectations (general guidance for deuterated lipid standards):

• Isotopic labeling: “‑d” denotes deuterium incorporation. The exact deuterium number and labeling positions critically affect mass spectrometric behavior (isotopic mass shift, retention time matching). This information is lot‑specific—verify on the CoA.
• Purity descriptors you may see in CoAs: Chemical purity (often by HPLC or LC‑MS), isotopic enrichment (atom % D), and isomeric composition (geometric isomers; R/S at C11 for racemates). For quantitative LC‑MS/MS, low levels of unlabeled 11‑HETE are important to minimize interference.
• Residual solvents/volatiles: High-end analytical standards may report residual solvents and water content (Karl Fischer). These are not specified here; consult the CoA if required by your method validation.
• Stabilizers: Some lipid standards are supplied with trace antioxidant (e.g., BHT) to limit autoxidation. Presence/absence and concentration of any stabilizer are item-specific; not specified for this item.
• Documentation: For regulated work (GLP/GMP bioanalysis), obtain CoA with traceability, lot number, test methods, and acceptance criteria. Consider verifying retention time, response factor, and isotopic purity in-house as part of method qualification.

When to choose this item:

• Use a deuterated 11‑HETE internal standard when quantifying endogenous 11‑HETE by LC‑MS/MS to correct for extraction efficiency, ion suppression, and matrix effects. Match the ion transitions and chromatographic behavior specified in your method.

Reaction and Applications

This product is primarily an analytical/internal standard rather than a synthetic reagent. Typical research applications (literature/general):

Analytical/lipidomics uses:

• Internal standard for quantitative LC‑MS/MS of endogenous 11‑HETE in plasma, serum, cell lysates, and tissue extracts. Deuteration provides a defined mass shift (Δm), co‑eluting species for matrix-matched quantitation, and correction for extraction losses and ion suppression.
• Method development/validation: Calibration curve preparation, accuracy/precision assessment, recovery, matrix effect studies, and stability testing (short‑term bench‑top, freeze–thaw, long‑term at −20 °C).
• Extraction workflows: Solid‑phase extraction (SPE, e.g., reverse phase or mixed‑mode weak anion exchange) and liquid–liquid extraction (e.g., MTBE/EtOAc) with internal standard spiked prior to extraction to normalize recovery.

Biochemical research:

• Tracing arachidonic acid metabolism pathways to hydroxyeicosatetraenoic acids under enzymatic (CYP/LOX) and non‑enzymatic oxidation conditions by using a deuterated reference to disambiguate isobaric interferences.
• Assay control in inhibitor screening targeting enzymes that generate or consume 11‑HETE (no biological efficacy implied).

Practical tips (general):

• Prevent oxidation/isomerization: Work cold, minimize light and oxygen, and prepare fresh working solutions. Consider amber glassware and inert gas.
• Adsorption control: Pre‑rinse plastics with solvent or use silanized glass to reduce losses.
• MS conditions: Negative‑ion ESI is commonly employed for eicosanoids. Optimize collision energies for the deuterated analog separately, as D‑labeling can slightly shift fragmentation pathways.

Reaction Conditions

As an analytical standard, (±)11‑HETE‑d is not typically “reacted,” but derivatization is common for GC‑MS or to modulate properties. The following are general literature conditions; adjust to your SOP and safety rules. These are not product specifications.

Common derivatizations:

• Methyl ester formation:
  • Reagent: Diazomethane in ether (classic) or trimethylsilyl‑diazomethane (safer alternative).
  • Conditions: 0–25 °C, minutes to 1 h; quench excess reagent; avoid moisture.
  • Notes: Preserves double‑bond geometry better than acid‑catalyzed methods; verify D‑label retention.
• BF3–MeOH esterification:
  • Reagent: 14% BF3–MeOH.
  • Conditions: 60–80 °C, 10–60 min.
  • Notes: Efficient but harsher; risk of double‑bond isomerization and H/D exchange—use caution.
• PFB ester formation (for GC‑NICI):
  • Reagent: Pentafluorobenzyl bromide + base (e.g., DIPEA) in acetonitrile/acetone.
  • Conditions: RT, 15–60 min.
  • Notes: Greatly enhances NICI sensitivity; minimize water.
• Silylation of 11‑OH:
  • Reagent: BSTFA (with 1% TMCS) or MSTFA.
  • Conditions: 60–70 °C, 15–30 min.
  • Notes: Protects hydroxyl and increases volatility; handle moisture‑free.

LC‑MS handling (non‑derivatized):

• Mobile phases: Water/MeOH or Water/ACN with 0.01–0.1% formic or acetic acid; negative‑ion ESI typically used.
• Columns: C18 or phenyl‑hexyl; sub‑2 µm or core‑shell for high resolution; temperatures 30–50 °C.
• Sample prep: Spike internal standard prior to extraction (protein precipitation, SPE, or LLE) to correct recovery.

Yields/metrics: Derivatization yields are generally high (>80% in literature best practices) but are method- and matrix‑dependent; confirm by recovery experiments using the deuterated standard.

Safety and Handling

Authoritative safety information should be obtained from the product SDS.

Item-specific hazard data (from Product Data):

• Signal word: Not specified for this item; refer to SDS.
• H‑statements: Not specified for this item; refer to SDS.
• GHS classification: Not specified for this item; refer to SDS.
• Pictograms: Not specified for this item; refer to SDS.

General safety considerations for polyunsaturated fatty acid derivatives and deuterated eicosanoids (literature/general guidance):

• Likely hazards: May cause skin and eye irritation; avoid inhalation of aerosols and ingestion. Handle in a chemical fume hood.
• Oxidation sensitivity: Polyunsaturated chains are prone to peroxidation and rancidity. Minimize exposure to air and light; consider handling under inert gas (N2/Ar) and including antioxidants in working solutions if compatible with your assay (check method/SOP).
• Thermal/light sensitivity: Store cold and protect from light to limit isomerization and decomposition.
• Incompatibilities: Strong oxidizers; bases promote soap formation (salts) and can alter extraction/assay behavior; avoid prolonged contact with reactive metals and peroxides.
• Recommended PPE: Lab coat, safety glasses, and appropriate chemical-resistant gloves (e.g., nitrile). Use secondary containment for solutions.
• First aid (overview): Skin—wash with soap/water. Eyes—rinse cautiously with water for several minutes; remove contacts. Inhalation—move to fresh air. Ingestion—rinse mouth; seek medical attention. Always follow your institution’s EHS procedures.

Storage and shipping (from Product Data):

• Storage: Store at −20 °C.
• Shipping: Ice chest + ice pads.

Waste: Dispose according to local regulations for organic chemical waste; avoid drain disposal. Contaminated absorbents/containers should be treated as chemical waste.

Solvent Selection

Solvent behavior (general/literature for 11‑HETE and deuterated analogs):

• Polarity class: Amphiphilic weak acid; overall highly lipophilic due to C20 chain but with polar –CO2H and –OH.
• Miscibility/solubility profile:
  • Water: Very limited solubility as free acid; improved as salt (e.g., Na+, K+) or when mixed with co‑solvent.
  • Alcohols (MeOH, EtOH, i‑PrOH): Good solubility; commonly used for stock solutions and LC mobile phases.
  • Aprotic polar (DMSO, DMF, ACN): Good solubility; DMSO is excellent for concentrated stocks but may not be ideal for all bioassays.
  • Halogenated (CH2Cl2, CHCl3): Excellent solubility; frequently used for extraction but less preferred for routine handling due to toxicity/volatility.
  • Esters/ethers (EtOAc, MTBE): Good solubility; useful in liquid–liquid extraction and SPE conditioning/elution.

Practical recommendations (method-dependent):

• Prepare concentrated stocks (e.g., 1–10 mg/mL) in ethanol, methanol, acetonitrile, or DMSO, then dilute into aqueous mobile phases containing 0.1% formic/acetic acid for LC‑MS. Use amber vials and inert gas headspace.
• For biological matrices, spike internal standard in a protein-precipitating solvent (MeOH or ACN) to ensure rapid mixing and reduce adsorption losses.
• Avoid neat aqueous solutions of the free acid; consider forming sodium salt in situ if aqueous work is essential, or maintain ≥50% organic co‑solvent.

Comparison (general):

• Ethanol vs DMSO: EtOH is greener and LC‑compatible; DMSO allows higher concentrations but can alter chromatography and ionization.
• ACN vs MeOH (LC): ACN often affords sharper peaks; MeOH can enhance negative‑ion ESI response for some eicosanoids—optimize empirically.

Storage and Reconstitution

Item-specific storage/shipping (from Product Data):

• Storage conditions: Store at −20 °C.
• Shipped in: Ice chest + ice pads.

General best practices for deuterated eicosanoid standards (literature/guidance):

• Light/oxygen protection: Store in amber vials under inert gas (N2/Ar). Minimize headspace and exposure to light to reduce autoxidation and isomerization.
• Aliquoting: Prepare small single‑use aliquots of concentrated stock to avoid repeated freeze–thaw cycles and adsorption losses on vial walls/caps.
• Reconstitution solvents: Ethanol, methanol, acetonitrile, or DMSO are commonly used for primary stocks. For aqueous systems, dilute into water with organic co‑solvent (≥50%) and weak acid (e.g., 0.1% formic or acetic) as compatible with your assay.
• Thawing: Warm to room temperature in the dark before opening to prevent moisture condensation. Briefly spin down to collect contents.
• Stability checks: Verify concentration periodically by LC‑MS/MS, especially after long storage or multiple thaw cycles. Prepare fresh working solutions frequently (e.g., daily/weekly) depending on your method’s stability data.
• Container choice: Use low‑adsorption, silanized glass or certified low‑bind plastics. Avoid rubber septa that may leach.

Note: Exact shelf life, stabilizers (if any), and solution stability are not specified for this item; refer to the CoA/Spec Sheet and the SDS, and confirm empirically under your laboratory conditions.

Research use: For research use only.

Structure and Identity

Brief description: (±)11-HETE-d is a deuterium-labeled, racemic monohydroxylated eicosatetraenoic acid standard, commonly used in lipidomics as an internal standard for quantifying endogenous 11‑HETE.

• SKU: H1447603
• Product name: (±)11-HETE-d
• CAS: 2750534-80-4
• Category: Life science research reagent; isotopically labeled eicosanoid standard (deuterated)

Item-specific identifiers (from Product Data):

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

Structural features (general/literature description):

• Core scaffold: C20 polyunsaturated fatty acid backbone bearing a terminal carboxylic acid (–CO2H) and a secondary alcohol at C11 (11‑hydroxy group).
• Unsaturation: Four carbon–carbon double bonds (eicosatetraene framework). Exact double-bond positions/geometry and deuterium placement can vary by supplier specification; consult CoA for this lot.
• Stereochemistry: Racemic at C11 for this listing ((±)). Double-bond geometries and any chiral centers beyond C11 are typically defined in detailed specs; not provided here.
• Isotopic label: Deuterium substitution (–d) at defined positions (commonly several non-exchangeable positions on the aliphatic chain). Label positions and D-count are item-specific; see CoA.

2D structure (verbal): A 20‑carbon chain ending in a carboxyl group at C1, containing four C=C bonds distributed along the chain, and a hydroxyl substituent at C11; selected hydrogens replaced by deuterium atoms on the chain (positions per CoA).

Synthetic Utility

While deuterated 11‑HETE is primarily an analytical standard, it can serve as a labeled substrate or intermediate in mechanistic and synthetic studies (general/literature):

Functional groups and reactivity:

• Carboxylic acid (–CO2H): Amenable to esterification (Fischer, Steglich) and amide formation (carbodiimides, uronium reagents). Methyl/ethyl esters improve volatility for GC‑MS or adjust lipophilicity.
• Secondary alcohol at C11: Can be protected (e.g., silyl ethers) or derivatized (e.g., acylation, carbamates). Oxidation affords the corresponding 11‑keto metabolite (11‑KETE).
• Polyunsaturation: Subject to epoxidation, dihydroxylation, or hydrogenation; caution that such reactions may scramble double‑bond geometry and compromise isotopic integrity.

Use cases:

• Isotopically labeled tracer: Map metabolic conversions by tracking deuterium retention/loss, distinguishing enzymatic vs non‑enzymatic pathways.
• Derivatization for analytics: Formation of pentafluorobenzyl (PFB) esters for GC‑MS with negative chemical ionization; trimethylsilyl (TMS) ether/ester derivatives to enhance volatility and MS response.

Caveats with D‑labeled substrates:

• Kinetic isotope effects can subtly alter reaction rates at labeled positions. Avoid labeling at reactive sites if you intend to mimic unlabeled behavior exactly (verify CoA for D positions).
• Acid/base exchange and protic conditions can lead to H/D exchange at activated positions; conduct reactions under dry, aprotic conditions when retention of deuterium is critical.

For rigorous synthetic applications, verify deuterium location and enrichment by NMR and HRMS before and after transformation.

Target Specificity

Not an antibody, enzyme, or receptor ligand product; no target specificity data are applicable.

Use context (general):

• Functions as an isotopically labeled internal standard for quantifying endogenous 11‑HETE by mass spectrometry. It does not possess “specificity” in the immunological sense; rather, its analytical utility derives from mass shift and chromatographic co‑elution relative to the unlabeled analyte.