Evaluation of surface-enhanced laser desorption time-of-flight mass spectroscopy in the development of biomarkers of occupational acrylamide exposure.
Am Lab 2011 Nov-Dec; 43(11):34, 36-39
Surface-enhanced laser desorption time-of-flight mass spectroscopy (SELDI-TOF-MS) is a bioanalytical technique used for the rapid examination of intact protein or protein mixtures to exploit the biochemical or biophysical characteristics of intact molecules to separate a complex protein mixture or isolate specific protein classes. Surface-enhanced laser desorption time-of-flight mass spectroscopy allows for rapid examination of protein components of body fluids or cell lysates without extensive extraction or preparative measures. The levels and composition of proteins found in blood and urine may change after exposure to toxic agents. Such potential changes make the proteins found in these easily obtained fluids a desirable source of new or altered proteins that indicate toxic exposure. This article describes the use of SELDI-TOF to examine urinary proteins or hemoglobin present in erythrocyte lysates. Acrylamide is a widely used industrial chemical intermediate with many applications, such as a polymerizing agent in grouts and in the preparation of laboratory gels for protein and nucleic acid electrophoresis. Low levels of acrylamide present in baked, fried, and roasted foods and in tobacco smoke are common sources of human exposure. Acrylamide is a potent neurotoxin and is a probable human carcinogen that makes exposure a concern for human health. Acrylamide and its metabolite glycidamide, also considered a toxicant, are reactive compounds and readily form adducts with biological macromolecules, including proteins. Both acrylamide and glycidamide react with hemoglobin (HGB), specifically at the N-(2 carbamoylethyl) valine residue of the ß-peptide subunit. These valine adducts are considered a biomarker of long-term acrylamide exposure. Possible reactions of acrylamide and glycidamide with other amino acids suggest that urinary proteins may be affected in acrylamide exposure. One of the goals of this work was to identify proteins in human urine modified by acrylamide exposure using SELDI-TOF-MS and four types of ProteinChip array (Bio-Rad Laboratories, Hercules, CA) to determine which array would be most useful for the planned analysis of urine from occupationally exposed workers. A second goal was to evaluate SELDI-TOF-MS as a low-cost, rapid screening method to demonstrate acrylamide or glycidamide adducted hemoglobin.
Biochemical-analysis; Biological-effects; Biomarkers; Biophysics; Blood-cells; Hemodynamics; Hemolysis; Hemoproteins; Mass-spectrometry; Measurement-equipment; Screening-methods; Statistical-analysis; Urine-chemistry
Patricia I. Mathias, NIOSH, US Dept Hlth & Human Serv,Robert A Taft Labs, Ctr Dis Control & Prevent,Assessment Branch, Div Appl Sci & Technol Biomonitoring & Hlth, 4676 Columbia Pkwy, Cincinnati, OH 45226
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