Magnetic graphene dispersive solid phase extraction-ultra performance liquid chromatography tandem mass spectrometry for determination of β-agonists in urine

Fluorescence immunoassay for simultaneous detection typical β-agonists in animal derived food using blue-green upconversion nanoparticles as labels

Common typical β-agonists mainly include ractopamine (RAC), salbutamol (SAL), and clenbuterol (CLB). In view of the harm to human health causes by the ingestion of animal derived food containing β-agonists, and a series of regulations have been issued to restrict the usage of β-agonists as growth promoters. In this work, a fluorescence immunoassay is developed for the simultaneous detection of typical β-agonists based on blue-green upconversion nanoparticles (UCNPs) combine with magnetic separation. Here, blue-green UCNPs act as a signal amplification source, and magnetic polystyrene microspheres (MPMs) act as an ideal separation medium. Based on a competitive form, capture probe competes (RAC-OVA@MPMs and SAL-OVA@MPMs) with targets to bind corresponding signal probe (anti-RAC antibody@NaYF4:Yb, Tm UCNPs and anti-SAL antibody@NaYF4:Yb, Er UCNPs). The fluorescence difference values of the competitive immune-complex obtained via magnetic separation at 483 nm and 550 nm are proportional to concentrations of RAC and SAL, respectively. The immunoassay has the wide detection linear range from 0.001 to 100 μg L-1, and the low limit of detection (LOD) is 5.04 × 10-4 μg L-1 for RAC, 1.97 × 10-4 μg L-1 for SAL, respectively. Meanwhile, use of antibody with same recognition ability for SAL and CLB makes that the fluorescence immunoassay can achieve simultaneous detection of three typical β-agonists (RAC, SAL, and CLB). This fluorescence immunoassay has good application value and practicability for simultaneous detection of typical β-agonists in animal derived food.

Novel vinylene-based covalent organic framework as a promising adsorbent for the rapid extraction of beta-agonists in meat samples

Beta-agonists are potent bronchodilators approved for the treatment of asthma and tocolysis. However, they have been extensively misused as feed additives in the veterinary field to improve feed efficiency. The concern over their potential hazard to health has come to the fore again. In this study, a novel vinylene-based covalent organic framework (V-COF-1) with a two-dimensional structure was developed. The structure shows good tolerance in a variety of mediums, which can be attributed to the low polarity linkage. The high specific surface area and variable interaction with analytes accelerate the extraction time. Furthermore, the swelling resulting from the formation of hydrogen bonds by the protic solvent intercalation with the triazine group also improves the adsorption efficiency. Finally, due to its great reusability, it is economical material in sample preparation application. The V-COF-1 based μ-dSPE approach was coupled with UHPLC-MS/MS to develop a highly sensitive and selective method. The linearity of the method ranged from 0.05 to 20 ng g^-1 with a correlation coefficient (R²) higher than 0.9958, and the limits of detection and quantification fell in the ranges of 0.01-0.10 ng g^-1 and 0.04-0.32 ng g^-1. The proposed method has been successfully applied to determine beta-agonists in meat samples, and the results indicated good recovery of 82.2-116%. The intra-day and inter-day precision were less than 6.61%, indicating the potential for sustainable application in food analysis.

Simultaneous determination of eight β-adrenergic agonists in human urine by an isotope dilution-online clean-up system coupled with liquid chromatography-tandem mass spectrometry

β-Adrenergic agonist compounds are medicines that open up the lung's medium and large airways. β-Adrenergic agonist compounds have been illegally or legally used to increase lean muscle mass in meat animals, bodybuilding, weight-loss programs, and athletes. Developing a rapid analytical approach for determining β-adrenergic agonist compounds in biological samples is crucial for individual exposure assessment. This study established an analytical method for simultaneously measuring eight β-adrenergic agonist compounds in human urine, including clenbuterol, terbutaline, salbutamol, ractopamine, zilpaterol, cimaterol, tulobuterol, and fenoterol. Two hundred microliters of a urine sample were added to eight deuterium-labeled internal standard mixtures and glucuronidase/arylsulfatase for enzymatic hydrolysis, and were then analyzed using an online clean-up system coupled with a liquid chromatography-tandem mass spectrometry system (LC-MS/MS). The limit of quantification ranged from 0.03 to 0.12 ng/mL urine for the eight β-adrenergic agonist compounds. The relative standard deviations (RSD) of the within-run and between-run precisions were less than 10%, and the relative accuracy errors were less than 17% in the three-level spiked artificial urine samples. Two hundred eighty human urine samples collected from the general population in Taiwan were assessed to demonstrate the capability and feasibility of this method. The detection frequencies were 33% for clenbuterol, 5% for ractopamine, and less than 5% for the others. We concluded that the isotope dilution-online clean-up system coupled with LC-MS/MS method is a valuable analytical method for investigating urinary β-adrenergic agonist compounds in humans and is valuable for human biomonitoring studies.

Analysis of β-blockers and β2-agonists in environmental and biological samples by magnetic solid-phase extraction combined with high-performance liquid chromatography-tandem mass spectrometry

β-Blockers and β2-agonists are commonly prescribed for therapeutic treatments and are also administered to livestock, leading to their presence in both environmental and biological samples. Hence, the development of sensitive, rapid, and reliable analytical methods for the determination of β-blockers and β2-agonists in environmental and biological samples is important. In this study, MIL-101(Cr)-NH₂ &GO-coated SiO₂ /Fe₃ O₄ magnetic particles were prepared as sorbents for magnetic solid-phase extraction and then combined with high-performance liquid chromatography-tandem mass spectrometry for the analysis of 20 β-blockers and eight β2-agonists. The experimental parameters of magnetic solid-phase extraction were studied in detail, and the optimal conditions were established. Under optimal conditions, the limits of detection were in the range of 0.002-0.007 μg/L with enrichment factors of 20.2-24.9. The developed method was successfully applied for the determination of 20 β-blockers and eight β2-agonists in river water, human urine, and freeze-dried pork liver powder. Bisoprolol and salbutamol were detected at concentrations of 2.78 mg/L in human urine and 11.5 μg/kg in freeze-dried pork liver powder.

Mixed mode monolithic sorbent in pipette tip for extraction of ractopamine and clenbuterol prior to analysis by HPLC-UV and UHPLC-Q ExactiveTM Plus Orbitrap MS

This work developed a fast and simple method for the quantification of two important β-agonists, ractopamine (RAC) and clenbuterol (CLEN) in animal urines. The method was based on micro-extraction by a mixed mode monolithic material and analysis by HPLC-UV and UHPLC-Q ExactiveTM Plus Orbitrap mass spectrometer. A mixed functional monolith with nonpolar ester-based structure containing polar carboxylic groups was thermally synthesized in situ in the pipette tips. The material combines both hydrophobic and ionic interactions. Parameters including conditions and composition of reagents for the in-pipette tip monolith synthesis, as well as the extraction process, were investigated and optimized. The procedure for extraction is 800 μL washing solvent of 10:90 (v/v) ACN:water and 150 μL eluting solvent of 30:70 (v/v) ACN:200 mM acetate buffer pH 4.0. Extraction efficiencies of 92% and 100% for RAC and CLEN, respectively, were achieved within 5 min with total organic solvent consumption of 395 μL. The extracts of spiked cattle and swine urines were analyzed by HPLC-UV and UHPLC-Q ExactiveTM Plus Orbitrap mass spectrometer. Good recovery with acceptable precision was observed. The mass spectrometry data confirmed efficient matrix removal by the synthesized extraction sorbent allowing routine analysis by the HPLC-UV method.

Application of magnetic nanomaterials in bioanalysis

The importance of magnetic nanomaterials and magnetic hybrid materials, which are classified as new generation materials, in analytical applications is increasingly understood, and research on the adaptation of these materials to analytical methods has gained momentum. Development of sample preparation techniques and sensor systems using magnetic nanomaterials for the analysis of inorganic, organic and biomolecules in biological samples, which are among the samples that analytical chemists work on most, are among the priority issues. Therefore in this review, we focused on the use of magnetic nanomaterials for the bioanalytical applications including inorganic and organic species and biomolecules in different biological samples such as primarily blood, serum, plasma, tissue extracts, urine and milk. We summarized recent progresses, prevailing techniques, applied formats, and future trends in sample preparation-analysis methods and sensors based on magnetic nanomaterials (Mag-NMs). First, we provided a brief introduction of magnetic nanomaterials, especially their magnetic properties that can be utilized for bioanalytical applications. Second, we discussed the synthesis of these Mag-NMs. Third, we reviewed recent advances in bioanalytical applications of the Mag-NMs in different formats. Finally, recently literature studies on the relevance of Mag-NMs for bioanalysis applications were presented.

Facile synthesis of magnetic sulfonated covalent organic framework composites for simultaneous dispersive solid-phase extraction and determination of β-agonists and fluoroquinolones in food samples

In this work, an efficient method for the determination of β-agonists and fluoroquinolones was established, based on a mixed-mode sorbent of magnetic sulfonated covalent organic framework composites. By coupling with HPLC-MS/MS, the main factors that affect the extraction procedure were optimized. Under the optimal conditions, the proposed HPLC-MS/MS method was successfully utilized for the extraction of β-agonists and fluoroquinolones in milk and pork meat samples. The method showed good linearities (R² ≥ 0.9916), and low LOQs of 0.1-0.2 ng g^-1 for β-agonists and fluoroquinolones. The adsorption mechanism was investigated with the assistance of quantum chemistry calculation method, and it is worth noting that the sorbent relied mainly on the multiple adsorption mechanisms, including π-π stacking, hydrophobic, electrostatic attraction and hydrogen-bonding interactions. This work not only provides a simple method for the preparation of a mixed-mode sorbent, but also a routine analysis strategy for monitoring the illegal use of β-agonists and fluoroquinolones.

Synthesis of 3D magnetic porous carbon derived from a metal–organic framework for the extraction of clenbuterol and ractopamine from mutton samples

Synthesis of MIL-100(Fe)-derived MPC and its application for the MSPE of CLB and RAC.