Analytical methods - Al
Aluminium can be difficult to solubilise when digesting a solid sample, so under reporting can occur. Inductively coupled plasma mass spectrometry (ICP-MS), after pressure microwave digestion, in accordance with DIN EN ISO 17294 (http://www.iso.org/iso/catalogue_detail.htm?csnumber=36127) is a method that has shown to give most accurate results.
An in vitro digestion method was used for estimating the bioaccessible fractions of (Al). The method is a three-step procedure where the human digestive process occurring in the mouth, stomach and intestine are simulated, using the synthetic digestive fluids, followed by an inductively coupled plasma optical emission (ICP-OES) determination (4).
A method for direct determination by SS-GF AAS was recently developed (5).
Recently, a new chemically modified electrode was constructed by incorporating AlMCM-41 into carbon paste matrix (AlMCM-41-MCPE) and used as a sensitive sensor for detection of aluminum in aqueous and non-aqueous solutions (6).
The IC (IC - Dionex, USA) speciation can clearly distinguish between organically bound Al and free Al3+ (Boruvka et al., 2009 and Street et al., 2007).
The widely used analytical techniques for the detection of the Al are the graphite furnace atomic absorption spectrometry (GF-AAS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) (Bocca et al., 2004, Polizzi et al., 2002, Popińska et al., 1999, Roberts et al., 1998 and Sanz-Medel et al., 2002).