HPLC Method for Pentetic Acid (DTPA) on Pentetic Acid (DTPA) by SIELC Technologies
Diethylenetriaminepentaacetic acid (DTPA) is a chelating agent with the chemical formula C14H23N3O10. It is used as a gadolinium chelate (Gd-DTPA) in MRI contrast agents to enhance the clarity of the images and in chelation therapy to treat poisoning by heavy metals like lead, plutonium, and americium by binding these metals and facilitating their excretion from the body. Agriculturally, DTPA is used to chelate micronutrients like iron, manganese, zinc, and copper in fertilizers, making these nutrients more available to plants, especially in alkaline soils where nutrients are less soluble. it is used in water treatment to sequester metal ions, preventing scale formation and improving the efficiency of detergents and cleaners and is included in formulations to stabilize and enhance the efficacy of cosmetic products by binding metal ions that might otherwise degrade the product. DTPA works by binding to metal ions through its multiple donor atoms (nitrogen and oxygen), forming stable, water-soluble complexes that can be easily excreted or removed. Its ability to form stable complexes with metal ions makes it valuable in treating metal poisoning, enhancing plant nutrition, and improving industrial processes. You can find detailed UV spectra of Pentetic Acid (DTPA) and information about its various lambda maxima by visiting the following link.
Pentetic Acid (DTPA) can be retained and analyzed on the Newcrom BH column with a mobile phase consisting of water and Acetonitrile (MeCN) This analytical method can be detected with high resolution and peak symmetry at a wavelength of 260 nm using UV detection
| Column | Newcrom BH, 3.2 x 150 mm, 5 µm, 100 A, dual ended |
| Mobile Phase | MeCN/H2O – 2/98% |
| Buffer | H2SO4 – 0.1% |
| Flow Rate | 0.5 ml/min |
| Detection | UV 260 nm |
| Injection volume: | 1 µl |
| Sample* | 0.1 mg/ml |
| Sample Diluent | 0.01 NaOH |
| LOD** | 5 ppb |
*Sample preparation:
DTPA Standards Solution A:
For the preparation of the DTPA standard solution, 5 mg of DTPA was accurately weighed and transferred into a 5 mL volumetric flask and dissolved in 0.01N NaOH water solution with sonication or magnetic stirrer mixing. Filtered The DTPA stock solution (1.0 mg/mL) should be stored in a cold dark place and can be used for a week to prepare standards of required concentration.
Iron(III) chloride Solution B:
The standard stock solution of Iron(III) chloride (10 mg/ml) was prepared in water. 50 mg of FeCl3 was accurately weighed and transferred into a 5 mL volumetric flask and dissolved in water, with sonication if needed.
General procedure for Ferric DTPA complex analysis:
To make a sample for analysis mix 100 µL Solution A (or unknown sample) with 300 µL Solution B and 600 µL of water. Place this mixture in a plastic HPLC vial for analysis. Setup instrument and column according to the method provided.
**LOD was determined for this combination of instrument, method, and analyte, and it can vary from one laboratory to another even when the same general type of analysis is being performed.
| Class of Compounds | Acid, Hydrophilic |
| Analyzing Compounds | Pentetic Acid (DTPA) |
Application Column
Newcrom BH
Column Diameter: 3.2 mm
Column Length: 150 mm
Particle Size: 5 µm
Pore Size: 100 A
Column options: dual ended
