PERFORMANCE OF TXRF and GI-XRF ANALYSES - Total-Reflection X-Ray Fluorescence Analysis and Related Methods - page 214

Objective Method Kind of Sample Physicochemical Process

Formation Suspension Aerosols, dust, ashes, sediments,

pulverized biomaterials

Fine distribution of insoluble particles in an aqueous
solution (water + ethanol) by stirring or
ultrasonication [8,9]

Dissolution Essential oils, air dust, filters Solution in a solvent (water, tetrahydrofurane,

chloroform) at moderate temperatures [10-12]

Decomposition Ashing Air dust on filters, blood serum,

edible oils, mineral oils, digested
fine roots

Ashing of the organic matrix (cellulose, protein) in an
oxygen stream by high-frequency heating [13-16]

Open digestion Suspended matter, aerosols on

filters, algae, blood, serum, tissue,
ashes, mud, sediment

Solution of the sample in concentrated acids or mixtures
(HNO 3 , HF, HCl) by a chemical reaction at moderate
temperature with infrared or microwave
heating [5,16-19]

Pressure digestion Dust on filters, lichen, minerals, soils,

mussels, and fish

Like open digestion but in a closed vessel (PTFE-bomb)
at high temperatures (150-300 ° C) and high pressures
of 10 6 -10 7 Pa [13,17,20]

Matrix removal Drying Rainwater, ultrapure acids Evaporation of the matrix by warming up, possibly in a

nitrogen stream [16,21,22]

Freeze-drying Drinking water, ultrapure water,

acids, organic solvents

Freezing of the matrix and evaporation under high
vacuum [5,21]

Volatilization Digests of Si and SiO 2 , sulfuric acid Volatilization of silicon as SiF 4 after addition of HF [23];

volatilization of sulfur as SO 2 after addition of HI [23]

Extraction Dissolved high-purity iron, digested

blood

Extraction of the iron matrix by MIBK [24]
Extraction of the Fe-component by MIBK [18]

Complexation Rain- and seawater

Digests of river water, blood and
aluminum

Separation of the alkaline, alkaline earth or aluminum
components by complexation as carbamates,
adsorption at chromosorb/cellulose, elution of the
traces [17,20,21,25,26]

Source : From Ref. [4], reproduced with permission. Copyright1996, John Wiley and Sons.