Metal Chelator

Pentetic acid is a pentacarboxylic acid. It has a role as a copper chelator. It is a conjugate acid of a pentetate(1-).
Pentetic acid, also known as diethylenetriaminepentaacetic acid (DTPA), is a synthetic polyamino carboxylic acid with eight coordinate bond forming sites that can sequester metal ions and form highly stable DTPA-metal ion complexes. DTPA, along with its calcium and zinc trisodium salts, are the only FDA approved agents for the treatment of internal contamination by transuranics. It is currently considered, in all the dosage forms, as a member of the list of approved inactive ingredients for drug products by the FDA. DPTA was developed by the pharmaceutical company CIS US and FDA approved on April 14, 2004.
Pentetic acid is a Lead Chelator. The mechanism of action of pentetic acid is as a Lead Chelating Activity.

DTPA is widely used in industry and medicine. As a medical agent, it is approved for its use in medical imaging and for the decorporation of internally deposited radionuclides. It is FDA approved for the treatment of individuals with known or suspected internal contamination with plutonium, americium or curium to increase the rates of elimination. Due to the pharmacokinetic elimination by the kidneys, pentetic acid conjugated with technetium Tc-99m is being used clinically to estimate physiological parameters such as glomerular filtration rat and effective renal plasma flow.

Pentetic Acid is an edetate and a chelating agent used in preparing radiopharmaceuticals. Pentetic acid (DTPA) has strong affinity for iron but also shows affinities for other heavy metals, thereby is used in the treatment of iron-storage disease and poisoning from heavy and radioactive metals. DTPA may chelate metallic moieties of unbound, extracellular radioimmunotherapeutics, thereby aggregating radioimmunotherapeutics locally to higher concentrations, and improving tumor cell radiocytotoxicity, while sparing normal tissues from the radiocytotoxic effects. In addition, DTPA is used in radioimaing procedures when complexes with radioisotopes, ex., Tc 99m or In 111.
An iron chelating agent with properties like EDETIC ACID. DTPA has also been used as a chelator for other metals, such as plutonium.

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Preparation of adsorbents [1]
The magnetic nanoparticles Fe3O4@SiO2 (FFO@Sil) and Fe3O4@SiO2@CS (FFO@Sil@Chi) were prepared respectively by Stöber method and water/oil emulsion crosslinking reaction, as detailedly stated can be found in Text S1. The Fe3O4@SiO2@CS-DTPA (FFO@Sil@Chi-DTPA) was fabricated via an amidation reaction. Firstly, 2 ml of Na5DTPA was dispersed in 60 ml of deionized water and adjust the mixture pH to about 5.5. After continuing the magnetic stirring of the liquid mixture for 1 h, add 60 ml of amidation reagent (ice water reagent with 5.32 g of EDC and 0.79 g of NHS), which was prepared in advance, continue stirring until a homogeneous solution was formed, and then added 1.1 g the prepared FFO@Sil@Chi into the above solution. After continuously stirring for another 8 h on a magnetic stirrer, the solid black product was obtained by magnetically separated. Then washed, dried, and recorded as adsorbent FFO@Sil@Chi-DTPA for experimental use. The other amidated adsorbent Fe3O4@CS-DTPA (FFO@Chi-DTPA) was also synthesized under the same experimental conditions as above. Scheme 1 shows the synthetic route of the adsorbents. Furthermore, the details of the characterization of the adsorbents can be seen in Text S2.

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Performance of adsorbents [1]
In this study, the adsorption experiment is divided into three parts. The first one is the adsorption of Pb(II) ions and MB in a single solution using the as-prepared adsorbents. The batch experiments were conducted to evaluate the adsorption kinetics, thermodynamics, isotherms, and effects of solution pH and ionic strength on uptake of each pollutant by as-prepared adsorbents. Secondly, the adsorption isotherms of the FFO@Sil@Chi-DTPA toward Pb (II) and MB in binary systems were also carried out. The last part is the competitive adsorption in the multi-ion coexisting solution or MB-multi-ion solution (coexistence of different concentrations of MB). All experiments were performed in triplicate, and the average value was used as the final result. All detailed instructions for the experiment are provided in the Supplementary Material (Text S4).

Absorption, Distribution and Excretion
DTPA and its trisodium salts have extremely low oral bioavailability. Therefore, DTPA is usually administered via slow intravenous infusion or nebulized inhalation. When inhaled, absorption is approximately 20% of the administered dose. DTPA metal complexes are rapidly excreted in the urine. It is primarily excreted via the kidneys, with almost no excretion outside the kidneys. The volume of distribution of DTPA is 17 liters. Pentetic acid has a very rapid blood clearance, which explains its short half-life. Clearance has been reported to be 80-120 ml/min in patients with normal renal function. Metabolism/Metabolites Pentetic acid and its derivatives are minimally metabolized in the body. Biological Half-Life Preclinical studies have shown that the half-life of DTPA after intravenous injection is short, ranging from 18.5 to 31.8 minutes.

Protein Binding
The rapid clearance and extremely short half-life of Pentetic acid suggest that this compound is highly unlikely to bind significantly to serum proteins. DPTA has been reported to bind negligibly to α1-antitrypsin. Adverse Reactions Reproductive Toxicity - Chemicals that are toxic to the reproductive system, including offspring defects and impairment of male or female reproductive function. Reproductive toxicity includes developmental effects. See the Reproductive Toxicity Risk Assessment Guidelines. 3053 Rat Intraperitoneal LD50 587 mg/kg Behavior: seizures or effects on the seizure threshold; Behavior: aggression; Lung, pleural, or respiratory: chronic pulmonary edema, Toxicology Letters, 32(37), 1986 [PMID:3090738] 3053 Mouse Intraperitoneal LD50 543 mg/kg, Archives of Toxicology, 57(212), 1985 [PMID:3933457]

[1]. Enhanced selective adsorption of lead(II) from complex wastewater by DTPA functionalized chitosan-coated magnetic silica nanoparticles based on anion-synergism. J Hazard Mater. 2022;422:126856.

Pentetic acid is a pentacarboxylic acid that acts as a copper chelating agent. It is the conjugate acid of the valerate (1-) group. Pentetic acid, also known as diethylenetriaminepentaacetic acid (DTPA), is a synthetic polyaminocarboxylic acid with eight coordination bond formation sites, enabling it to chelate metal ions and form highly stable DTPA-metal ion complexes. DTPA and its calcium, sodium, and zinc sodium salts are currently the only drugs approved by the FDA for the treatment of transuranic internal contamination. Currently, all dosage forms of DTPA are listed by the FDA as inactive ingredients in pharmaceutical products. DTPA was developed by the pharmaceutical company CIS US and approved by the FDA on April 14, 2004. Pentetic acid is a lead chelating agent. Its mechanism of action is the chelation of lead. Pentetic acid is an ethylenediaminetetraacetic acid (EDTA) chelating agent used in the preparation of radiopharmaceuticals. Pentetic acid (DTPA) has a strong affinity for iron, but also for other heavy metals, thus it can be used to treat iron metabolism disorders and heavy metal and radioactive metal poisoning. DTPA can chelate the metal fractions of free extracellular radioimmunotherapy drugs, thereby increasing the local concentration of the drug, enhancing the radiotoxicity of tumor cells, and protecting normal tissues from radiotoxicity. In addition, DTPA is also used in radiographic imaging when it forms complexes with radioisotopes such as Tc-99m or In-111. It is an iron chelating agent with properties similar to ethylenediaminetetraacetic acid (EDTA). DTPA can also be used as a chelating agent for other metals such as plutonium.
See also: Trisodium calcium pentanoate (active fraction); Trisodium zinc pentanoate (active fraction); Disodium indium-111 pentanoate (active fraction).
Pharmaceutical Indications
DTPA has wide applications in industry and medicine. As a medical drug, it is approved for medical imaging and for the removal of radionuclides deposited in the body. It has been approved by the FDA for the treatment of patients with known or suspected plutonium, americium, or curium contamination in the body to improve the clearance rate of radionuclides. Because it is cleared by renal pharmacokinetics, pentiformin bound to technetium-99m is clinically used to assess physiological parameters such as glomerular filtration rate and effective renal plasma flow.
FDA Label

Mechanism of Action

DTPA's calcium and zinc sodium salts exert their therapeutic effect by exchanging calcium and zinc ions with transuranic radionuclides to form high-affinity complexes, thereby promoting their entry into the urine through glomerular filtration. As an acid, DTPA's mechanism of action is very similar, utilizing its eight coordination bonds to form chelate ions.
Pharmacodynamics

In vivo studies have reported that the complexes formed by DPTA with uranium and neptunium are less stable, leading to radionuclide deposition in tissues. For plutonium, some preclinical studies have shown very high urinary excretion efficiency within 1 hour of initial contamination. This efficiency can be maintained for approximately 24 hours during radiocontaminant circulation. DPTA has been reported to reduce lung deposits by up to 98% after inhalation of radionuclides.
It is worth noting that Pentetic acid can directly bind to other trace metals in the body, leading to metal deficiency. Simultaneously removing heavy metals and dyes from complex wastewater is of great significance for industrial wastewater treatment. This paper successfully prepared a novel magnetic adsorbent—DTPA-modified chitosan-coated magnetic silica nanoparticles (FFO@Sil@Chi-DTPA)—and utilized anionic synergy to enhance its selective adsorption of Pb(II) in multi-metal wastewater. In competitive experiments conducted in multi-ion solutions, the selective adsorption type of the adsorbent for metals changed before and after amidation. Specifically, FFO@Sil@Chi-DTPA exhibited excellent selective adsorption capacity for Pb(II), while FFO@Sil@Chi showed highly selective adsorption capacity for silver. More importantly, under pH 6.0 conditions, when the concentration of coexisting MB increased from 0 to 100 mg L⁻¹, the selective adsorption capacity of FFO@Sil@Chi-DTPA for Pb(II)S increased from 111.71 mg g⁻¹ to 268.01 mg g⁻¹. In the Pb(II)-MB binary system, Pb(II) and MB exhibit a synergistic effect. The presence of MB enhances the adsorption effect of Pb(II) because the sulfonic acid group in the MB molecule provides a new specific site for the adsorption of Pb(II); at the same time, the presence of Pb(II) also enhances the adsorption effect of MB. This work provides a new strategy for exploring novel adsorbents that can enhance the selective removal of heavy metals from complex wastewater based on anionic synergistic effects. [1]

C14H23N3O10

393.35

393.138

C, 42.75; H, 5.89; N, 10.68; O, 40.67

67-43-6

3053

White to off-white solid powder

1.5±0.1 g/cm3

721.1±60.0 °C at 760 mmHg

219-220 °C(lit.)

389.9±32.9 °C

0.0±5.0 mmHg at 25°C

1.590

0.05

5

13

16

27

481

0

C(CN(CC(=O)O)CC(=O)O)N(CCN(CC(=O)O)CC(=O)O)CC(=O)O

QPCDCPDFJACHGM-UHFFFAOYSA-N

InChI=1S/C14H23N3O10/c18-10(19)5-15(1-3-16(6-11(20)21)7-12(22)23)2-4-17(8-13(24)25)9-14(26)27/h1-9H2,(H,18,19)(H,20,21)(H,22,23)(H,24,25)(H,26,27)

2-[bis[2-[bis(carboxymethyl)amino]ethyl]amino]acetic acid

Penthamil (VAN); Acidum penteticum; diethylenetriaminepentaacetic acid; 67-43-6; DTPA; Detapac; Detarex; Titriplex V; Perma kleer; Pentetic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~5 mg/mL (~12.71 mM)

Solubility in Formulation 1: ≥ 0.5 mg/mL (1.27 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 5.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 0.5 mg/mL (1.27 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 5.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 0.5 mg/mL (1.27 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 5.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)