Rapid and simultaneous relaxometric methods to study paramagnetic ion complexes in solution: An alternative to spectrophotometry

Author(s)

Crizostomo Kock, Flavio Vinicius ^[1] ; Colnago, Luiz Alberto ^[2]

Affiliation

^[1] Univ Sao Paulo, Inst Quim Sao Carlos, BR-13566590 Sao Carlos, SP - Brazil

^[2] Embrapa Instrumentacao, BR-13560970 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Microchemical Journal; v. 122, p. 144-148, SEP 2015.
• Web of Science Citations: 11

Abstract

T-1 and T-2 relaxation times, measured with rapid and simultaneous continuous wave free precession (CWFP) and Carr-Purcell-continuous wave free precession (CP-CWFP) pulse sequences were used to study complexes of EDTA with paramagnetic ions in solution. The relaxation times of Cu(II)-EDTA and {[}CuEDTA(center dot)NH(3)](-2) complexes, from pH 1 to 13, measured in a 0.47 T time-domain nuclear magnetic resonance (TD-NMR) spectrometer show good agreement with the absorbance at approximately 730 nm. These methods were also used to study colorless complexes containing paramagnetic ions, not accessible by electronic spectroscopy, such as Mn(II)-EDTA. Therefore, these sequences can be used in any bench top TD-NMR spectrometers as faster alternative to spectrophotometry in analytical routine analyses. (C) 2015 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 12/23169-8 - In situ study of action of quitosan biopolymer in the decontamination of metals and herbicides in aqueous system by electrochemistry coupled to high and low field NMR
• Grantee: Flavio Vinicius Crizostomo Kock
• Support Opportunities: Scholarships in Brazil - Doctorate