Diethylenetriaminepentaacetic acid DTPA

Alkaline-earth metals are often deterruined volumetricaHy by complexometric titration at pH 10, using Eriochrome Black T as indicator. The most suitable complexing titrant for barium ion is a solution of diethylenetriaminepentaacetic acid (DTPA). Other alkaline earths, if present, are simultaneously titrated, and in the favored analytical procedure calcium and strontium are deterruined separately by atomic absorption spectrophotometry, and their values subtracted from the total to obtain the barium value. 

The chelates employed were diethylenetriaminepentaacetic acid (DTPA), 1,2-... 

No reports were located regarding death in humans that could be associated with acute-, intermediate,- or chronic-duration dermal exposure to americium. An explosion and accidental exposure of a 64-year-old man to 1-5 Ci (37-185 GBq) of241 Am was followed by immediate treatment to reduce contamination to approximately 6 mCi (222 MBq) and to 1 mCi (37 MBq) after the first day (Thompson 1983 Toohey and Kathren 1995). Survival was likely the result of intense and long-term chelation therapy, such as with diethylenetriaminepentaacetic acid (DTPA). The patient lived until natural death 11 years after the accident (see Section 3.2.3.2 for more detailed information regarding this accidental exposure and subsequent treatment and follow-up). 

Open-chain ligands were the first evaluated for complexation studies with indium and yttrium. The use of diethylenetriaminepentaacetic acid (DTPA) anhydride permitted early evaluation of labeled chelate-conjugates (Figure 2).80 The use of this activated chelating agent was quite popular, until the drawbacks associated with its crosslinking of proteins became apparent. 

Citric acid and nitriloacetic acid (NTA) lanthanide complexes were used in the earliest ion exchange separations of lanthanides from fission product mixtures (Kf = 3.2 for Ce(H3 Cit.)3 and Kf = 10.8 for CeNTA2) (Sillen and Martell, 1964). More recently such polyamino-polycarboxylic acids as ethylenediaminetetraacetic acid (EDTA), 1,2-diaminocyclohexaneacetic acid (DCTA), and diethylenetriaminepentaacetic acid (DTPA) have been prepared. Their lanthanide complexes are very stable (Table 3) and have been widely used in analysis and separation of lanthanide mixtures. They have also been used experimentally to remove internally-deposited 144Ce and other radioactive lanthanide nuclides from animals and man (Foreman and Finnegan, 1957 Catsch, 1962 Balabukha et al., 1966 Palmer et al., 1968 among others). 

Baybarz, R. D. (1965). Dissociation contents of the transplutonium chelates with diethylenetriaminepentaacetic acid (DTPA) and the application of DTPA chelates to solvent extraction separations of transplutonium elements from the lanthanide elements, J. Inorg. Nucl. Chem. 27,1831. 

Liu and others (Liu et al., 2007) conjugated polyethylene glycol (PEG) to C60 (C60-PEG), and diethylenetriaminepentaacetic acid (DTPA) was subsequently introduced to the terminal group of PEG to prepare C60-PEG-DTPA that was mixed with gadolinium acetate solution to obtain Gd3+-chelated C60-PEG-DTPA-Gd. Following intravenous injection of C60-PEG-DTPA-Gd into tumor-bearing mice, the PDT... 

The removal of thorium from the body has been achieved by the use of chelating agents, primarily ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) (Fried and... 

Promethium—147, the isotope used commercially, is isolated from fission product wastes. The radioactive materials must be handled safely in a glove box. The metal complexes either with ethlenediaminetetraacetic acid (EDTA) or diethylenetriaminepentaacetic acid (DTPA) and is isolated by elution from Dowex 50. 

Sander and Henze [50] have performed ac investigations of the adsorption potential of metal complexes at Hg electrode. Later, Sander etal. [51] have studied electrosorption of chromium - diethylenetriaminepentaacetic acid (DTPA) on mercury in 0.1 M acetate buffer at pH 6.2 using a drop-time method. The changes in the interfacial activity of the Cr(III)-DTPA complex with the bulk concentration obeyed the Frumkin adsorption isotherm. 

BH4 in CSF is sensitive to auto-oxidation, and correct sample collection and storage are essential for the performance of the method. CSF (1 ml) should be collected in tubes containing 1 mg DTE and 1 mg diethylenetriaminepentaacetic acid (DTPA). Samples should be immediately stored at -70°C [14]. 

The most common and best known chelant is ethylenediaminetetraacetic acid (EDTA). The related compounds diethylenetriaminepentaacetic acid (DTPA) and nitrilotriacetic acid (NTA) are also well known (Figure 10.2). EDTA is a powerful chelant that complexes strongly with most metal ions to form six-coordinate complexes. It has therefore become the first choice in most applications. Indeed, a search of the bathroom cabinet will spot EDTA on the ingredient list of many personal care formulations. DTPA is also a powerful chelant, but tends to be used more often in industrial settings. NTA has only four binding sites and is used more often where hardness ions require control, such as in cleaning, for example, hard surface cleaners, dishwashing, and the dairy industry. 

A mixture of well-known extractants, di-(2-ethylhexyl)phosphoric acid (HDEHP) and CMPO, in n-paraffin was used for the study of combined extraction of different actinides (americium, plutonium, and uranium) and lanthanides (cerium and europium) and their separation from fission products (cesium, strontium, ruthenium, and zirconium).54 Combined extraction of MAs and lanthanides was studied together with group separation of MAs from lanthanides by selective stripping with a solution of diethylenetriaminepentaacetic acid (DTPA), formic acid, and hydrazine hydrate. This solution strips only MAs, leaving lanthanides in the organic phase. Subsequently, the lanthanides are stripped using a mixture of DTPA and sodium carbonate. 

Because the drug and the mobilized metals are excreted via the urine, the drug is contraindicated in anuric patients. Nephrotoxicity from EDTA has been reported, but in most cases this can be prevented by maintenance of adequate urine flow, avoidance of excessive doses, and limitation of a treatment course to 5 or fewer consecutive days. EDTA may result in temporary zinc depletion that is of uncertain clinical significance. An experimental analog of EDTA, calcium disodium diethylenetriaminepentaacetic acid (DTPA), has been used for removal ("decorporation") of uranium, plutonium, and other heavy radioisotopes from the body. 

Alkylphosphonate groups are monodentate donors of intermediate hardness that may replace carboxylate groups in chelating agents such as nitrilotriacetic acid (NTA), ethylenediaminetetra-acetic acid (EDTA), and diethylenetriaminepentaacetic acid (DTPA). The corresponding ligands nitrilotrimethylenephosphonic acid (NTP), 1, ethylenediaminetetramethylenephosphonic acid (EDTP),... 

Fig. 63. Xanthene-modified diethylenetriaminepentaacetic acid (dtpa) derivatives.

Other non-cyclic ligands can be used to bind Gd3+ with most based on the diethylenetriaminepentaacetic acid (DTPA) skeleton. These include GdDTPA, or Magnevist [31], and a di(methyl)amide derivative GdDTPA-BMA, or Omniscan [32], illustrated in Fig. 6.13. 

Fig-1 Schematic presentation of the radiopharmaceutical design. The targeting biomolecule serves as the vehicle to carry a radionuclide to the receptor site on tumor cells. The radionuclide is the radiation source. The bifunctional chelator (BFC) is used for radiometal chelation and attachment of the targeting molecule. The linker is often used for modification of pharmacokinetics. Diethylenetriaminepentaacetic acid (DTPA), 1,4,7,10-tetraaza-cyclododecane-N>N, N">Ar,"-tetraacetic acid (DOTA)... 

Diethylenetriaminepentaacetic acid (DTPA) possesses amine and carboxylic acid functional groups and could form octadentate complexes with heavy metals. It is used as a chelator to determine metal bioavailability in soil to plants and mobility to the aquatic environment. 

The L1 complexes of the middle lanthanides Gd(III), Eu(III), and Tb(III) decompose less rapidly at pH 7.4, 37 °C than do the L1 complexes of La(III) or Lu(III) (14). The fit of the lanthanide ion into the macrocycle may be important here. Certainly, the macrocycle fit will vary for La3+ (116 pM) compared to Lu3+ (97.7 pM) (41). A recent study using luminescence measurements suggests a greater lability of the Eu(L1)3+ complex than previously reported (28). Detection of the Eu(DPTA)-complex produced upon addition of diethylenetriaminepentaacetic acid (DTPA) to Eu(L1)3+ indicates that the complex decomposes approximately 12% in 48 h at 37 °C, pH 7.4. It is noteworthy that solutions of Eu(L1)3+ contain two different species (28). One of them, possibly a hydroxy-bridged dimer, is present in greater amounts at high concentrations of Eu(L1)3+. 

A sample of 0. IM solution diethylenetriaminepentaacetic acid (DTPA) (1 eq) in acetonitrile was treated with triethylamine (5 eq) and degassed for 20 minutes before heating for 1 hour at 50 °C. The solution was then cooled to 45°C, treated with the dropwise addition of isobutylchloro-fomate (1.1 eq), and stirred for 1 hour. This mixture was next treated with the Step 1 product (1 eq) dissolved in acetonitrile and stirred 12 hours at ambient temperature. The solution was concentrated, the residue re-cry staUized from THF and diethyl ether, and the product isolated as a white solid. 

Domingo JL, de la Torre A, Belles M, et al. 1997. Comparative effects of the chelators sodium 4,5-dihydroxybenzene-l,3-disulfonate (tiron) and diethylenetriaminepentaacetic acid (dtpa) on acute uranium nephrotoxicity in rats. Toxicology 118( 1 ) 49-59. 

Studies of Ni(ii) complexes with the potentially 8-donor ligand diethylenetriaminepentaacetic acid (DTPA) over a wide pH range have shown (144) that only some of the carboxylic groups coordinate to the nickel ion. Deuteration studies have enabled the rate constants for the exchange between coordinated and uncoordinated carboxylic groups to be evaluated. 

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