**11. References**


[6] Dekant W. The role of biotransformation and bioactivation in toxicity. EXS. 2009;99:57- 86.

118 Chromatography – The Most Versatile Method of Chemical Analysis

DMPK, drug metabolism and pharmacokinetic; CYP, cytochrome P450; UGT, UDPglucuronosyltransferase; NAT, N-acetyltransferase; GST, glutathione-S-transferase; SULT, sulfotransferase; UDPGA, uridine diphospoglucuronic acid; PAPS, phospohoadenosine phosphosulfate; HLM, human liver microsomes; LC-MS, liquid chromatography-mass spectrometry; LC-MS/MS, liquid chromatography-tandem mass spectrometry; GC-MS, gas chromatography-mass spectrometry; CE, capillary electrophoresis; LC-NMR, liquid chromatography-nuclear magnetic resonance; HPLC, high performance liquid chromatography; UHPLC, ultra-high performance liquid chromatography; HILIC, hydrophilic interaction chromatography; PGC, porous graphic carbon; RAD, radioactivity detector; MS, mass spectrometry; MS/MS, tandem mass spectrometry; API, atmospheric pressure ionization; ESI, electrospay ionization; APCI, atmospheric pressure chemical ionization; APPI, atmospheric pressure photoionization; QQQ, triple quadrupole; IT, ion trap; QTrap, triple quadrupole-linear ion trap; TOF, time of flight; Q-TOF, triple quadrupole-time of flight; FT-ICR, fourier transform-ion cyclotron resonance; IM-MS, ion mobility mass spectrometry; MRM, multiple reaction monitoring; SRM, selected reaction monitoring; SIM, single ion monitoring; CNL, constant neutral loss scan; PI, precursor ion scan; PP, protein precipitation; LLE, liquid-liquid extraction; SPE, solid-phase extraction;

RAM, restricted access materials; ME, matrix effect; IS, internal standard.

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**Chapter 5** 

© 2012 Lucci et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2012 Lucci et al., licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

**Current Trends in Sample Treatment Techniques** 

Nowadays, there is a growing need for applications in food and environmental areas able to cope with the analysis of a large number of analytes in very complex matrices [1]. The new analytical procedures demand sensitivity, robustness, effectiveness and high resolution with reduced analysis time. Many of these requirements may be met to a certain extent by the total or partial automation of the conventional analytical methods, including sample preparation or sample pre-treatment coupled on-line to the analytical system. Furthermore, the recent use of ultra-high-performance liquid chromatography (UHPLC) for environmental and food chemical analysis has increased the overall sample throughput and laboratory efficiency without loss (and even with an improvement) of resolution obtained

Nonetheless, despite the advances in chromatographic separations and mass spectrometry techniques, sample treatment is still one of the most important parts of the analytical process and effective sample preparation is essential for achieving good analytical results [1]. Ideal sample preparation methods should be fast, accurate, precise and must keep sample integrity. Therefore, over the last years, considerable efforts have been made to develop modern approaches in sample treatment techniques that enable the reduction of the analysis time without compromising the integrity of the extraction process. The use of on-line solidphase extraction (SPE), which minimizes sample manipulation and provides both high preconcentration factors and recoveries [2-5], is an increasingly powerful and rapid technique used to improve the sample throughput and overcome many of the limitations associated with the classical off-line SPE procedure. However, in most of the cases, matrix related compounds may also be co-extracted and could interfere in the analysis. Consequently, in order to minimize the effect of all these possible interferences a selective clean-up step may be required. Higher specificity and selectivity together with satisfactory extraction efficiency can be obtained using sorbents based on molecularly imprinted polymers (MIPs) [6-8].

**for Environmental and Food Analysis** 

Paolo Lucci, Deborah Pacetti, Oscar Núñez and Natale G. Frega

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/47736

by conventional HPLC systems.

**1. Introduction** 

