Simultaneous determination of coinage metals, copper, silver, and gold in tissues using electrospray ionization tandem mass spectrometry

Abstract

A rapid and sensitive mass spectrometric method was developed for the simultaneous determination of coinage metals such as copper (Cu), silver (Ag) and gold (Au). The metals in a wet ashed tissue solution were complexed with diethyldithiocarbamate (DDC; C 4 H 10 NCS 2) and were extracted together with isoamyl alcohol. After the acidification of the extract with oxalic acid, metals were quantified using their product ions, Cu(DDCH) + , Ag(DDCH) + and Au(DDCH) + that derived from the precursor ions Cu(DDC) 2 + , Ag(DDC) 2 + and Au(DDC) 2 + , respectively, by electrospray ionization tandem mass spectrometry. The limits of detection were 0.6, 0.3 and 1 gl-1 for Cu, Ag and Au and the quantification ranges were 2-100, 1-100 and 3-100 gl-1 for Cu, Ag and Au, respectively. Cu levels in spontaneously hypertensive osteogenic disorder rats at 6 weeks old and at 30 weeks old were found to be 1.8 times and 5.1 times those of the normotensive osteogenic disorder rats, respectively, when using wet-ashed kidney solutions diluted to 1,000 fold.

A novel method for determination of inorganic oxyanions by electrospray ionization mass spectrometry using dehydration reactions

“…Although these techniques deliver impressive analytical performance, researchers in this field continue to seek improvements in sensitivity, selectivity and convenience. For instance, electrospray ionization MS (ESIMS) has attracted a wide interest as testified in a number of recent studies …”

“…The use of ESIMS and complexation–extraction techniques for sample pretreatments has been extensively developed by Minakata et al . for trace analysis …”

“…used diethyldithiocarbamate (DDC) and pyrrolidine dithiocarbamate (PDC) to ligate metal and metalloid ions and to extract the complexes into the organic phase. Methods were described for determinations of cobalt, platinum, molybdenum, ruthenium, hexavalent chromium, copper, silver and gold based on DDC and for determinations of arsenic(III) and arsenic(V) in clinical samples using PDC. A novel method was also proposed for trace metal analyses based on negative ion mode ESIMS, where metal–aminopolycarboxylate (metal–APC) complexes, particularly those of trans ‐1,2‐diaminocyclohexane‐ N , N , N ′, N ′‐tetraacetic acid (CyDTA), were measured after online separation of the complexes from sample matrices with a size exclusion column.…”

Highly Selective Detection of Trace Copper(II) Using Bathocuproinesulfonate by Flow-Injection Electrospray Ionization Mass Spectrometry

“…It has also often been used as an analytical method to measure the speciation of metal complexes, based on their nature. [1][2][3][4] Typically, a heavy metal ion in a water sample that is softly ionized by ESI forms various metal-hydration complexes. 5 Therefore, the coordination of a target metal ion and a chelating agent can prevent this hydration, and can effectively separate the ion from coexisting-ionic species.…”

“…For example, several researchers have reported [2][3][4] the quantification and speciation of metal complexes with chelating agents, such as ethylenediaminetetraacetate (EDTA) or diethyldithiocarbamate (DDC).…”