Detection of β-Lactams and Chloramphenicol Residues in Raw Milk—Development and Application of an HPLC-DAD Method in Comparison with Microbial Inhibition Assays

Abstract

The present study was carried out to assess the detection sensitivity of four microbial inhibition assays (MIAs) in comparison with the results obtained by the High Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) method for antibiotics of the β-lactam group and chloramphenicol in fortified raw milk samples. MIAs presented fairly good results when detecting β-lactams, whereas none were able to detect chloramphenicol at or above the permissible limits. HPLC analysis revealed high recoveries of examined compounds, whereas all detection limits observed were lower than their respective maximum residue limits (MRL) values. The extraction and clean-up procedure of antibiotics was performed by a modified matrix solid phase dispersion procedure using a mixture of Plexa by Agilent and QuEChERS as a sorbent. The HPLC method developed was validated, determining the accuracy, precision, linearity, decision limit, and detection capability. Both methods were used to monitor raw milk samples of several cows and sheep, obtained from producers in different regions of Greece, for the presence of examined antibiotic residues. Results obtained showed that MIAs could be used effectively and routinely to detect antibiotic residues in several milk types. However, in some cases, spoilage of milk samples revealed that the kits’ sensitivity could be strongly affected, whereas this fact does not affect the effectiveness of HPLC-DAD analysis.

Determination of Aflatoxin M1 in Raw Milk Using an HPLC-FL Method in Comparison with Commercial ELISA Kits—Application in Raw Milk Samples from Various Regions of Greece

“…However, most of the chromatographic methods employ solid phase pretreatment and immunoaffinity techniques to eliminate interferences and improve the analysis of mycotoxins [ 19 ]. Furthermore, the HPLC method requires complicated and time-consuming sample preparation, resulting in the consumption of many chemical solvents [ 20 ]. For this reason, at the routine level and in research studies, immunological methods are preferred more than chromatographic, such as Enzyme-Linked-Immunosorbent Assay (ELISA) [ 21 , 22 ].…”

Synthesis of Graphene Oxide Based Sponges and Their Study as Sorbents for Sample Preparation of Cow Milk Prior to HPLC Determination of Sulfonamides

“…Sulfonamides are a group of synthetic antibacterial agents, which are widely used in veterinary practice for prophylactic and therapeutic purposes and as feed additives. Due to their ability to inhibit folic acid synthesis in microorganisms, they are commonly used against a wide range of bacteria, protozoa, parasites, and fungi [1,2,3].…”

On Column Binding a Real-Time Biosensor for β-lactam Antibiotics Quantification

“…Antibiotics are commonly utilized for the treatment of infectious diseases as a means for disease prevention (prophylaxis) in animals. The fast appearance of resistant bacteria is emerging as a potential threat in the next decades, while the extensive use of therapeutic or sub-therapeutic dosages of antibiotics that are used in farms to enhance growth is considered to be important factor that significantly influences the development of bacterial multidrug-resistance [2,5,30]; therefore, consumer and regulatory agencies have a high concern regarding antibiotic residues in food-producing animals.…”