Fast analysis of 19 anabolic steroids in bovine tissues by high performance liquid chromatography with tandem mass spectrometry

Development of a method for the determination of sedatives in bovine and porcine urine and kidneys by liquid chromatography-tandem mass spectrometry

Introduction

Sedatives have been used for a long time as animal tranquillisers to prevent stress and weight loss during their transportation. The proper determination of these substances in food of animal origin is essential for consumer safety.

Material and Methods

A 1 g portion of pig or cow urine or homogenised kidney was mixed with acetonitrile, sodium chloride was added, and the solution was further mixed and then centrifuged. The supernatant was transferred to a new centrifuge tube with primary and secondary amine, octadecylsilane and ZrO2, and mixed rapidly. The filtered solution was evaporated under a nitrogen stream. The residue was dissolved in 200 μL of acetonitrile, centrifuged with filters and then transferred to vials. Samples were analysed by high-performance liquid chromatography-tandem mass spectrometry.

Results

The decision limit for confirmation was calculated at 2.5 μg kg-1 for all sedatives with relative standard deviation repeatability and reproducibility below 20%.

Conclusion

The validation results showed that this method meets the pertinent EU criteria for such methods and is suitable for sedative analysis in urine and kidney matrices.

Determination of anabolic androgenic steroids in dietary supplements and external drugs by magnetic solid-phase extraction combined with high-performance liquid chromatography-tandem mass spectrometry

The widespread abuse of anabolic androgenic steroids by healthy people leads to the risk of major mood disorders and heart failure; thus, the determination of anabolic androgenic steroids is vital. In this study, 17 anabolic androgenic steroids in dietary supplements and external drugs were identified, and their concentration was determined. For this purpose, polyaniline-coated magnetic nanoparticles were prepared and then subjected to magnetic solid-phase extraction combined with high-performance liquid chromatography-tandem mass spectrometry. The experimental parameters of magnetic solid-phase extraction were studied in detail, and the optimal conditions were established. Under the optimal conditions, the limits of detection were in the range of 0.001-0.02 μg/L, with relative standard deviations of 5.52-11.6% (n = 7) for all the steroids, and the enrichment factors were in the range of 20.0-24.8. The developed method was then successfully applied for the determination of 17 anabolic androgenic steroids in real samples, and dehydroepiandrosterone (prasterone) was detected in a commercially available external drug.

Hormones and Hormonal Anabolics: Residues in Animal Source Food, Potential Public Health Impacts, and Methods of Analysis

The demand for nutritious food, especially food of animal origin, is globally increasing due to escalating population growth and a dietary shift to animal source food. In order to fulfill the requirements, producers are using veterinary drugs such as hormones and hormone-like anabolic agents. Hormones such as steroidal (estrogens, gestagens, and androgens), nonsteroidal, semisynthetic, and synthetic or designer drugs are all growth-promoting and body-partitioning agents. Hence, in food animal production practice, farm owners use these chemicals to improve body weight gain, increase feed conversion efficiency, and productivity. However, the use of these hormones and hormonal growth-promoting agents eventually ends up with the occurrence of residues in the animal-originated food. The incidence of hormone residues in such types of food and food products beyond the tolerance acts as a risk factor for the occurrence of potential public health problems. Currently, different international and national regulatory bodies have placed requirements and legislative frameworks, which enable them to implement residue monitoring test endeavors that safeguard the public and facilitate the trading activity. To make the tests on the animal-origin food matrix, there are different sample extraction techniques such as accelerated solvent extraction, supercritical fluid extraction, solid phase extraction, solid-phase microextraction, and hollow-fiber liquid-phase microextraction. After sample preparation steps, the analytes of interest can be assayed by screening and confirmatory methods of analysis. For screening, immunological tests such as ELISA and radioimmunoassay are used. Detection and determination of the specific residues will be done by chromatographic or instrumental analysis. Mainly, among high-performance liquid chromatography, liquid chromatography with mass spectrometry (LC-MS, LC-MS/MS), and gas chromatography with mass spectrometry (GC-MS and GC-MS/MS) methods, LC-MS/MS is being preferred because of easier sample preparation without a derivatization step and high detection and quantification capacity.

Single-particle-frit-based packed columns for microchip chromatographic analysis of neurotransmitters

The fabrication of effective microchip liquid chromatography (LC) systems tends to be limited by the availability of suitable chromatographic columns. Herein, we developed a glass microchip LC system in which porous single-particle silica was adopted as frits and a freeze-thaw valve was utilized to achieve sample injection without interfering with sampling. The fabrication of single-particle-frit-based packed columns did not require an additional packing channel, thus avoiding dead volumes within the channel interface that can influence chromatographic separation. Further, the length of the packed column could be adjusted using the location of single-particle frits within the column channel. The fabricated frits exhibited high mechanical strength, good permeability, and tolerance for high pressures during chromatographic separation. In particular, the developed microchip LC system was able to withstand high separation pressures of more than 5000 psi. The microchip LC system was applied to the separation of neurotransmitters. Three different monoamine neurotransmitters were completely separated within 5 min with theoretical plate numbers on the order of 100,000 plates m^-1. The microchip LC system has a potential for application in a variety of fields including environmental analysis, food safety, drug analysis, and biomedicine.

Screening for twenty-eight target anabolic-androgenic steroids in protein supplements using QuEChERS extraction followed by liquid chromatography-tandem mass spectrometry

Anabolic-androgenic steroids (AASs) are very potent muscle builders, and professional sportsmen often take protein supplements to improve their performance. Several studies have emphasised that protein supplements may contain undeclared AASs banned by the International Olympic Committee/World Anti-Doping Agency. The widespread occurrence and abuse of contaminated protein supplements is extremely dangerous because of their side effects. To minimise the chances of an unattended positive doping test or to avoid serious health problems, adequate screening methods for the detection of a wide range of steroids is essential. To address this requirement, a rapid and effective modified QuEChERS (quick, easy, cheap, effective, rugged and safe) method was developed and validated to screen and quantify the simultaneous analysis of twenty-eight AASs in protein supplements using LC-MS/MS. The validated method was applied to 198 protein supplements collected from on-line and, off-line markets, and direct purchase from overseas between 2019 and 2020. Of the 198 samples, two samples contained testosterone and stanozolol at concentrations of 0.27 μg/g and 0.023 μg/g, respectively. In addition, 5α-hydroxylaxogenin was detected for the first time in three products purchased in Korea from overseas. The modified QuEChERS method was established and successfully applied to screen and determine AASs as a measure of continuous control and supervision in protein supplements.