Ce-MXRF: the power of separation with bench top element sensitive detection

Conference · Tue Jan 01 04:00:00 EST 2002

OSTI ID:976233

Miller, T C ^[1]; Joseph, M R ^[2]; Havrilla, G J ^[3]

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1. Thomasin C.
2. Martha R.
3. George J.

Capillary electrophoresis (CE) is a proven separation technique that offers highly efficient separation, rapid analysis, and minute sample consumption. When combined with a element specific detection scheme, it can be used for chemical speciation of biologically and environmentally relevant species such as metal containing proteins. In this study, a new tool was developed for separation and elemental detection. Specifically, a simple CE apparatus was constructed using a thin-walled fused Si capillary and interfaced with a bench top micro x-ray fluorescence (MXRF) system. X-ray excitation and detection of the separated sample volumes was performed using an EDAX Eagle II micro x-ray fluorescence system equipped with a Rh target excitation source and a SiLi detector. It was demonstrated that the system could be used for the separation and detection of two metals from one another, specifically Cu{sup 2+} and Co{sup 2+}. Free Co{sup 2+} could also be isolated from Co{sup 2+} bound to cyanocobalamin (Vitamin B-12). Other systems that were explored were the separation of two organics, ferritin from cyanocobalamin as well as the separation of the different Cu and Zn isoforms of metallothinein. CE-MXRF was also used to separate the important serum isoforms of transferrin. Direct comparisons were made between CE-MXRF system and other elemental separation techniques such as CE-PIXE, CE-synchrotron-XRF, and CE-ICPMS.

• Research Organization: Los Alamos National Laboratory
• Sponsoring Organization: DOE
• OSTI ID: 976233
• Report Number(s): LA-UR-02-4576
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
99 GENERAL AND MISCELLANEOUS
DETECTION
ELECTROPHORESIS
EXCITATION
FERRITIN
FLUORESCENCE
PROTEINS
TARGETS
TRANSFERRIN
VITAMIN B-12