| Size | Price | Stock | Qty |
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| 10mg |
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| Other Sizes |
| Targets |
The compound targets primary amines (N-termini, lysine side chains) of affibody molecules, antibodies, and peptides. The NHS ester forms a stable amide bond. The chelated radiometal is the active component; for imaging, ⁶⁸Ga or ⁶⁴Cu is used for PET; for therapy, ¹⁷⁷Lu or 22⁵Ac is used for targeted radionuclide therapy (TRT) of tumors (e.g., HER2-positive cancer).
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| ln Vitro |
In vitro, DOTA-NHS-ester TFA is used to conjugate DOTA to affibody molecules. The conjugated affibody is radiolabeled with ⁶⁸Ga (pH 4.0-5.0, 95degC, 10-15 min) to form ⁶⁸Ga-DOTA-affibody. The radiolabeled probe has high affinity (Kd low nM) for HER2 receptors on cancer cells and can be used for PET imaging. The compound itself is not biologically active.
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| ln Vivo |
In vivo, DOTA-NHS-ester TFA is used to prepare radiopharmaceuticals for PET/CT imaging of HER2-positive tumors. ⁶⁸Ga-DOTA-affibody injected intravenously (1-10 MBq, 0.1-1 nmol) into mice bearing HER2+ xenografts (e.g., SKOV-3). PET/CT images show high tumor uptake (SUV >5) and low background at 1-2 h post-injection. For therapy, ¹⁷⁷Lu-DOTA-affibody (10-50 MBq) inhibits tumor growth.
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| Enzyme Assay |
For conjugation, affibody (1-5 mg/mL) in 0.1 M NaHCO3 (pH 8.5) is incubated with DOTA-NHS-ester TFA (5-20× molar excess) at 4degC for 2-4 h. Unreacted chelator is removed by dialysis (3.5 kDa MWCO) or size-exclusion chromatography. Conjugation efficiency is determined by MALDI-TOF MS (increase in molecular weight). For radiolabeling, DOTA-affibody (10-50 ug) in 0.25 M NaOAc (pH 4.5) is mixed with ⁶⁸GaCl3 (1-10 mCi) and heated at 95degC for 15 min. Radiochemical purity (>95%) is assessed by ITLC and HPLC.
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| Cell Assay |
For cell assays, SKOV-3 cells are seeded in 24-well plates (2 × 10⁵ cells/well). ⁶⁸Ga-DOTA-affibody (1-10 nM, 0.1 uCi) is added, with and without excess unlabeled affibody (100 nM). After 1 h at 4degC, cells are washed, and bound radioactivity is measured in a gamma counter. For cytotoxicity, DOTA-NHS-ester TFA alone (1-100 uM) is not toxic (IC₅0 >100 uM).
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| Animal Protocol |
For in vivo imaging, female BALB/c nude mice bearing SKOV-3 xenografts (200-300 mm3, n=5) are injected intravenously with ⁶⁸Ga-DOTA-affibody (5-10 MBq, 0.1-0.5 nmol). Dynamic PET/CT scans are acquired at 15, 30, 60, 120, and 240 min. SUV values are calculated. Ex vivo biodistribution: mice are euthanized at 2 h, and organs (tumor, liver, spleen, kidneys) are harvested and counted in a gamma counter. For therapy, ¹⁷⁷Lu-DOTA-affibody (10-30 MBq) is injected IV; tumor volumes are measured over 4 weeks.
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| ADME/Pharmacokinetics |
DOTA-NHS-ester TFA is soluble in DMSO (100 mg/mL) and slightly soluble in water. The DOTA chelator is stable at pH 4-8. Radiometal complexes are inert and stable in vivo. After IV injection of ⁶⁸Ga-DOTA-affibody, the radiotracer clears rapidly from the blood (t½ 15-30 min) and is excreted renally.
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| Toxicity/Toxicokinetics |
The chelator itself (DOTA-NHS-ester) has low toxicity (LD₅0 > 2000 mg/kg). Radiometal complexes have toxicity associated with the radionuclide (e.g., myelosuppression, nephrotoxicity) at therapeutic doses (¹⁷⁷Lu). Acute toxicity is not significant at imaging doses. No genotoxicity.
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| References | |
| Additional Infomation |
DOTA-NHS-ester TFA is a research reagent for radiopharmaceutical preparation. It is not an FDA-approved drug, but DOTA-containing radiopharmaceuticals (e.g., ⁶⁸Ga-DOTATATE) are FDA-approved for clinical use. The compound is used to radiolabel affibodies for HER2-positive cancer imaging and therapy. For research use only.
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| Molecular Formula |
C22H32F3N5O12
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|---|---|
| Molecular Weight |
615.51
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| Appearance |
White to off-white solid powder
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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 Note: (1). Please store this product in a sealed and protected environment, avoid exposure to moisture. |
| 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 | 1.6247 mL | 8.1233 mL | 16.2467 mL | |
| 5 mM | 0.3249 mL | 1.6247 mL | 3.2493 mL | |
| 10 mM | 0.1625 mL | 0.8123 mL | 1.6247 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.
Products are for research use only; We do not sell to patients
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