Current trends in sample preparation by solid-phase extraction techniques for the determination of antibiotic residues in foodstuffs: a review

The presence of antibiotic residues in foodstuff has been of growing concern in recent years. They are associated with several adverse effects on human health such as the transmission of antibiotic-resistant pathogenic bacteria through the contaminated food, weakness of the immune system, allergic or toxic reactions and imbalance of the gut microbiota. Therefore, monitoring of the levels of antibiotic residues in animal-derived food is necessary to guarantee the safety of food products as well as the public health. Since the residual antibiotics in the foodstuff are in trace levels which are often lower than the limits of detection of analytical instruments, the sample preparation before the analysis is very important. This step is an essential part of an analytical process, especially for the extraction of chemical residues from a sample, preconcentration of the extract and elimination of any matrix interferences that may affect the selectivity, sensitivity and the overall performance of the analytical methods. Solid-phase extraction (SPE) is one of the most widely used techniques for the sample preparation that provides an efficient and reproducible method for selective concentration of target analytes in complex matrices. The objective of this research was to provide an updated overview of the recent trends in SPE techniques over the past five years. Different variations of this method, including solid-phase microextraction, stir bar sorptive extraction, matrix solid-phase dispersion, micro-solid-phase extraction, dispersive micro solid-phase extraction, magnetic solid-phase extraction, and molecularly imprinted solid-phase extraction are also given in the present study. The review is focused on recent developments and innovations in the SPE which tries to improve the efficiency, safety and performance of sample preparation.