Matrix solid phase dispersion MSPD

MSPD first reported by Barker et al. [32] is a powerful technique for disrupting and extraction of solid, semi-solid and viscous samples. A small amount of sample is homogenized with bulk-bonded silica sorbent (typical ratio 1:4) with a glass pestle in a glass mortar. The shearing forces disrupt the structures of the matrix and disperse the sample over the surface of the sorbent. The homogeneous blend of sorbent and sample is then packed in a syringe-type cartridge (like an SPE cartridge) followed by elution of targets and interfering compounds (or vice versa) by consecutive washings with appropriate solvents. For non-fatty matrices, a simultaneous clean-up often occurs during the MSPD process which allows direct analysis of the extracts [33] while further clean-up is required for MSPD extracts of fatty matrices. An elegant way to remove fat traces was described by Ferrer et al. [34]. Olives and the acetonitrile extract of olive oil were homogenized with aminopropyl silica and the obtained powder was loaded on a Florisil SPE cartridge. Elution with acetonitrile gave a nearly fat free extract. This method is compared to the conventional procedure of size exclusion clean-up.

The practical and theoretical aspects of MSPD are described in Ref. [35]. A recent review by Barker [36] contains numerous applications illustrating that the method has found wide application in the analysis of contaminants and pesticide residues from animal tissues, fruits, vegetables and other matrices.

0 0

Post a comment