Recent approaches for on‐line analysis of residues and contaminants in food matrices: A review†

Abstract

This review highlights recent developments for on-line determination of residues and contaminants in complex matrices such as food samples. This involves the on-line coupling of a sample preparation technique (as the first "dimension") with a chromatographic system (second "dimension"), usually followed by mass spectrometry. Although frequently treated as quite distinct techniques, the role of all devices utilized as the first dimension in this approach aims to decrease the sample complexity while eliminating as much as possible the matrix contaminants to facilitate the qualitative and quantitative determination of the compounds of interest. This review will focus on the following techniques as the first dimension: (i) on-line solid-phase extraction; (ii) in-tube solid-phase microextraction; (iii) matrix solid-phase dispersion; and (iv) turbulent flow chromatography. The second dimension is usually performed using a chromatographic column to isolate the analyte(s) of interest for further mass spectrometry determination. A description of the basis of this on-line approach and its distinct set up possibilities is presented, which is followed by a critical review of the literature covering this subject in the last ten years (focusing on the last five years) with emphasis on the analysis of residue and contaminants in food samples.

Recent advances and future trends in new materials for sample preparation

“…Combining the well-known advantages of full methodological automation, as provided by on-line techniques [12], with the use of more selective, more appropriate, novel sorption materials yet to be developed, we can easily envisage "green extraction techniques" being an important and fruitful research area in the decades ahead. Table 3.…”

“…According to this approach [12], not covered in this review, the sample is introduced into a small apparatus (column, tubing, bar, or similar device) that acts as the sample-preparation step. This device is connected to a switching valve so that, after the extraction, solvent or temperature will desorb the analytes trapped into this device to the analytical column where the separation is performed.…”

“…The middle box (sample preparation) illustrates the new materials employed in the main sorbent-based techniques, surrounded by the main modern sample-preparation techniques that utilize these materials. The last box (separation techniques) illustrates the separation techniques usually employed in combination (on-line or off-line) with these samplepreparation techniques, concluding the typical analytical workflow utilized for the analysis of complex samples [12], as presented and discussed in this work. The period covered in this review includes 2004-2014, with emphasis on the last five.…”

An overview of multidimensional liquid phase separations in food analysis

“…There have been several recent reviews of 2D separations published over the past decade . The present review focuses on recent advances with special attention given to 2D condensed‐phase separations applied to food analysis with focus on food safety.…”

Analysis of lignans in Magnoliae Flos by turbulent flow chromatography with online solid‐phase extraction and high‐performance liquid chromatography with tandem mass spectrometry

“…Turbulent flow chromatography (TF) is a method based on the principle of SEC to separate small molecule drugs from complex biological fluids such as urine, plasma, vitreous humor, and postmortem tissues . By using the online TF column for online SPE, the pretreatment can be direct and fast .…”