| Size | Price | Stock | Qty |
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| 50mg |
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| 100mg |
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| Other Sizes |
| Targets |
DOTA‑NHS‑ester targets primary amines on proteins and peptides through the NHS ester functionality. Once conjugated, the DOTA cage chelates radiometals, including ⁶⁸Ga, ⁶⁴Cu, ¹⁷⁷Lu, ⁹⁰Y, and 22⁵Ac, with high thermodynamic stability and kinetic inertness. The compound is used in tumor pre‑targeting strategies, such as the preparation of PSMA‑targeting ligands for PET imaging or radiotherapy.
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| ln Vitro |
In vitro, DOTA‑NHS‑ester is used to label targeting ligands. A typical labeling protocol: 0.1 mM peptide (e.g., PSMA‑617) is incubated with 0.3 mM chelator in 100 mM HEPES buffer (pH 8.5) at 37 degC for 1-2 h. Conjugation efficiency (>95%) is confirmed by HPLC‑MS. The DOTA‑peptide is then purified by solid‑phase extraction and radiolabeled with ⁶⁸Ga or ¹⁷⁷Lu (40 degC, 15-30 min). The radiochemical purity often exceeds 98%.
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| ln Vivo |
DOTA‑NHS‑ester is not directly administered to animals; it is a precursor for synthesizing radiopharmaceuticals. The final radiolabeled conjugate (e.g., [⁶⁸Ga]Ga‑DOTA‑PSMA‑617) is injected intravenously (50-200 microL, 10-20 MBq) into mice bearing PSMA‑expressing tumors. PET/CT imaging shows high tumor uptake (SUV>5) and rapid renal clearance, with minimal non‑specific retention in non‑target organs.
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| Enzyme Assay |
To assess conjugation efficiency, the DOTA‑NHS‑ester (10 mM in anhydrous DMSO) is added to an amine‑containing peptide (1 mM in 0.1 M NaHCO3, pH 8.5) at a 3:1 molar ratio. The mixture is incubated at 25 degC for 2 h. The reaction is quenched with 50 mM Tris (pH 8) and analyzed by MALDI‑TOF. The shift in m/z corresponds to the number of DOTA groups attached (one per molecule is typical). Unconjugated chelator is removed by dialysis or SEC.
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| Cell Assay |
No direct cellular assay is performed with the chelator alone. After conjugation to a targeting peptide (e.g., RGD or PSMA‑617), the DOTA‑conjugate is radiolabeled with ⁶⁸Ga (25-50 microL of 0.05 M HCl eluate, 5 min, 95 degC) and diluted in PBS. Cells (5×10⁵) are incubated with the labeled conjugate (10 nM) at 4 degC for 1 h, then washed. Cell‑associated radioactivity is measured with a gamma counter. Specificity is confirmed by blocking with a 100‑fold excess of unlabeled peptide.
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| Animal Protocol |
For animal imaging, a radiolabeled DOTA‑peptide (10-20 MBq) is injected intravenously into mice (n=4-6) bearing subcutaneous xenografts of a target‑expressing cell line (e.g., LNCaP for PSMA). Static PET/CT scans are performed at 1, 2, and 4 h post‑injection. At the final time point, animals are euthanized, and organs are harvested for ex vivo gamma counting to calculate %ID/g. The compound shows high stability with minimal bone uptake.
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| ADME/Pharmacokinetics |
The pharmacokinetics of the radiolabeled DOTA‑peptide conjugate are well‑characterized. The plasma half‑life is typically 1-4 h in mice, depending on the peptide size. Clearance occurs predominantly via the renal route. The parent chelator has no intrinsic PK properties. When conjugated, the DOTA chelate remains highly stable in vivo, with <5% transchelation over 24 h as measured by blood sampling and HPLC.
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| Toxicity/Toxicokinetics |
The free chelator is not for human use. Toxicity data for the chelator alone are limited. As an NHS ester, it is a reactive compound that can cause severe skin and eye burns. The radiolabeled conjugate's toxicity is primarily due to radiation exposure. At typical diagnostic doses (10-20 MBq), no acute toxicity is observed in mice. The chelator itself should be handled with caution in a fume hood with appropriate PPE.
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| Additional Infomation |
DOTA‑NHS‑ester hexafluorophosphate TFA is not a drug but a key building block for radiotracer synthesis. It is used to prepare PSMA inhibitors for PSMA‑targeted imaging and therapy (e.g., [⁶⁸Ga]Ga‑PSMA‑11, [¹⁷⁷Lu]Lu‑PSMA‑617), which are FDA‑approved for prostate cancer management. The compound is also used for tumor pre‑targeting and radioimmunotherapy research. It is a research‑only reagent and not intended for human injection.
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| Molecular Formula |
C20H31N5O10.C2HF3O2.F6P.H
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|---|---|
| Molecular Weight |
761.48
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| CAS # |
1823122-52-6
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| Appearance |
Typically exists as solid at room temperature
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| Melting Point |
176-179°C
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| HS Tariff Code |
2934.99.9001
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| Storage |
Powder -20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month |
| Shipping Condition |
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
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| Solubility (In Vitro) |
May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples
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| Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.
Injection Formulations
Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)(e.g. IP/IV/IM/SC) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). View More
Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] Oral Formulations
Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). View More
Oral Formulation 3: Dissolved in PEG400 (Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 1.3132 mL | 6.5662 mL | 13.1323 mL | |
| 5 mM | 0.2626 mL | 1.3132 mL | 2.6265 mL | |
| 10 mM | 0.1313 mL | 0.6566 mL | 1.3132 mL |
*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.
Calculation results
Working concentration： mg/mL；
Method for preparing DMSO stock solution： mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.
Method for preparing in vivo formulation:：Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O，mix and clarify.
(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
(2) Be sure to add the solvent(s) in order.
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