Spectroscopic studies of citrulline and its metal complexes in aqueous solutions

CHED 1224

Felicia Marie Magnaterra, fmagnaterra@mytsu.tnstate.edu1, Emanuel A. Waddell, ewaddell@chemistry.uah.edu2, Stephen Shreeves2, Anderson Sunda Meya, asundame@xula.edu3, and Nsoki Phambu, nphambu@tnstate.edu1. (1) Department of Chemistry, Tennessee State University, 3500 John A. Merritt Blvd., Nashville, TN 37209, (2) Chemistry, University of Alabama in Huntsville, MSB 203C, John Wright Drive, Huntsville, AL 35899, (3) Department of Physics and Dual Engineering, Xavier University of Louisiana, 1 Drexel Drive, New Orleans, LA 70125
Citrulline is an amino acid that is a key intermediate in the urea cycle, the pathway by which mammals excrete ammonia. The binding of metal ions to citrulline and the effect that metal ions have on the structure of citrulline is of great interest. Complexes of lead, arsenic, cadmium, mercury I and II, chromium, and iron ions with citrulline in aqueous solution at different pHs and metal ion concentrations have been investigated using infrared, Raman, and 1H NMR techniques. The infrared and Raman spectra show dramatic changes in the position and intensity of the amide and carboxylic bands of citrulline upon metal complexation, which indicates that the structure is affected. The 1H NMR spectra indicate that the amide and carboxylic groups of citrulline are deprotonated in the presence of these metal ions. The relative stability constants for the binding of citrulline by metal ions were determined by potentiometric titrations
 

Undergraduate Research Poster Session: Inorganic Chemistry
2:00 PM-4:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Poster

Division of Chemical Education

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008