Electrochemical detection of aminoglycoside antibiotics residuals in milk based on magnetic molecularly imprinted particles and metal ions

Electrochemical detection of tetracycline by zinc oxide modified with molecularly-imprinted polymers

An efficient electrochemical molecularly imprinted sensor for the detection of tetracycline (TC) was prepared using ZnO/MIP. ZnO nanomaterials with large surface area improved the electrochemical detection performance and also increased the binding sites of the TC molecularly imprinted polymeric membrane. The TC molecularly imprinted polymeric membrane with pyrrole as the functional monomer specifically binds to TC and thus detects TC in the sample. In this study, the electrochemical performance of ZnO/MIP was evaluated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under the optimal conditions, ZnO/MIP showed a wide detection range. The detection range was 0.1-100 nM, and the detection limit was 0.02 nM with R2 reaching 0.9974. ZnO/MIP has good selectivity, stability, and reproducibility. The recovery of tetracycline in milk was 97-112%.

A review on molecularly imprinted magnetic solid phase extraction emphasizing the analysis of antibiotics in complex matrices:Design, preparation, and application

Magnetic solid phase extraction (MSPE) has been widely employed in the isolation and enrichment of antibiotics in complex matrices because it presents various unique advantages over traditional SPE including simple operation, fast extraction procedure, low cost and eco-friendliness. In recently years, magnetic molecularly imprinted nanoparticles (MMINs) containing highly specific recognition performance have been widely used to specific extraction of antibiotics under the format of MSPE. In this connection, recent advances of MMINs in the analysis of antibiotic residues are reviewed. Firstly, the common structure of MMINs including core-shell, core-satellite, cavity structure and nanotube/nanosheet-supported structurewere introduced. After that, a main section covers the synthesis strategies of MMINs including one-step preparation and multi-steps preparation (precipitation polymerization, emulsion polymerization, suspension polymerization and surface imprinting technique) were illustrated. Furthermore, the applications of MMINs in the selective extraction of various antibiotic residues (sulfonamides, quinolones, tetracyclines, β-lactams, aminoglycosides and so on) in environmental and food samples were summarized. Finally, the existing problems and future prospects of MMINs were outlined in the final section of the review.

Surface-enhanced Raman spectroscopy substrates for monitoring antibiotics in dairy products: Mechanisms, advances, and prospects

Antibiotic residues in dairy products have become an undeniable threat to human health. Surface-enhanced Raman spectroscopy (SERS) has been widely used in efficiently detecting antibiotics because of its characteristics including fast response, high resolution, and strong resistance to moisture interference. However, as a core part of SERS technology, the design principle and detection performance of enhanced substrates used in monitoring antibiotics in dairy products have not yet received enough attention. Thus, it is necessary to give a critical review of the recent developments of SERS substrates for monitoring antibiotics in dairy products, which can be expected to provide inspiration for the efficient utilization of SERS technology. In this work, advances in various SERS substrates applied in sensing antibiotics in dairy products were comprehensively reviewed. First, the enhancement mechanisms were introduced in detail. Significantly, the types of enhanced materials (plasmonic metal particles [PMPs], PMPs/semiconductor composite materials) and biometric design strategies including immunoassay, aptamer, and molecularly imprinted polymers-based SERS biosensors applied in dairy products were systematically summarized for the first time. Meanwhile, the performance of SERS substrates used for the detection of antibiotics in dairy products was addressed from the aspects of dynamic linear range and detection restriction strategy. Finally, the conclusions, challenges, and future prospects of SERS substrates for antibiotic monitoring in dairy products were deeply discussed, which also provide new opinions and key points for constructing SERS substrates applied in complex food matrix in the future.

Ag-modified CuO cavity arrays as a SERS-electrochemical dual signal platform for thiram detection

Rapid and sensitive determination of pesticide residues in fruits and vegetables is critical for human health and ecosystems. This paper used an Ag-modified CuO sphere-cavity array (CuO@Ag) electrode as a thiram SERS/electrochemical dual readout detection platform. Numerous Raman "hotspots" generated by uniformly distributed silver nanoparticles, charge transfer at the CuO@Ag interface, and the formation of Ag-thiram complexes contribute to the significant enhancement of this SERS substrate, which results in excellent SERS performance with an enhancement factor up to 1.42 × 106. When using SERS as the readout technique, the linear range of the substrate for thiram detection was 0.05-20 nM with a detection limit (LOD) of up to 0.0067 nM. Meanwhile, a correlation between the value of change in current density and thiram concentration was established due to the formation of stable complexes of thiram with Cu2+ generated at specific potentials. The linear range of electrochemical detection was 0.05-20.0 μM, and the detection limit was 0.0167 μM. The newly devised dual-readout sensor offers notable sensitivity and stability. The two signal readout methods complement each other in terms of linear range and detection limit, making it a convenient tool for assessing thiram residue levels in agro-food. At the same time, the combination of commercially available portable equipment makes on-site monitoring possible.

An advanced ratiometric molecularly imprinted sensor based on metal ion reoxidation for indirect and ultrasensitive glyphosate detection in fruit

An indirect and ultrasensitive ratiometric molecularly imprinted (MIP) sensor, based on metal ion reoxidation, is introduced for glyphosate (GLY) determination in fruit. As high-performance signal amplification substrates, carbon nanotubes (MWCNTs) and gold nanoparticles (AuNPs) are conveniently modified on GCE. The artificial antibody-MIP membrane, presents typical three-dimensional structure to GLY template. Built-in reference methylene blue (MB) is directly electropolymerized on MWCNTs-Au/GCE. Particularly, Cu2+ and GLY interestingly form chelate complex, and the Cu2+ (ICu) in Cu(Ⅱ)-GLY-complex can be reoxidized, and indirectly quantizes GLY. The reference signal (IMB) presents noteworthy stability with different GLY levels, and the ratiometric readout (ICu/IMB) is recognized as a more trustworthy indicator to quantize GLY. Proposed sensor presents broad range as 1.73 ∼ 400 ng/mL, and limit of detection is well found as 0.24 ng/mL (S/N = 3). Finally, as-fabricated method is verified with standard HPLC in real-fruit-sample, and the errors and recovery rates are calculated as 3.4% ∼ 6.7% and 94.4% ∼ 104.6%, respectively.

Development of Novel Peptide-Modified Silver Nanoparticle-Based Rapid Biosensors for Detecting Aminoglycoside Antibiotics

The detection and monitoring of aminoglycoside antibiotics (AGAs) have become of utmost importance due to their widespread use in human and animal therapy, as well as the associated risks of exposure, toxicity, and the emergence of antimicrobial resistance. In this study, we successfully synthesized casein hydrolysate peptides-functionalized silver nanoparticles (CHPs@AgNPs) and employed them as a novel colorimetric analytical platform to demonstrate remarkable specificity and sensitivity toward AGAs. The colorimetric and spectral response of the CHPs@AgNPs was observed at 405 and 520 nm, showing a linear correlation with the concentration of streptomycin, a representative AGA. The color changes from yellow to orange provided a visual indication of the analyte concentration, enabling quantitative determination for real-world samples. The AgNP assay exhibited excellent sensitivity with dynamic ranges of approximately 200-650 and 100-700 nM for streptomycin-spiked tap water and dairy whey with limits of detection found to be ∼98 and 56 nM, respectively. The mechanism behind the selective aggregation of CHPs@AgNPs in the presence of AGAs involves the amine groups of the target analytes acting as molecular bridges for electrostatic coupling with hydroxyl or carboxyl functionalities of adjacent NPs, driving the formation of stable NP aggregates. The developed assay offers several advantages, making it suitable for various practical applications. It is characterized by its simplicity, rapidity, specificity, sensitivity, and cost-effectiveness. These unique features make the method a promising tool for monitoring water quality, ensuring food safety, and dealing with emergent issues of antibiotic resistance.

A molecularly imprinted electrochemical sensor for specific and ultrasensitive determination of an aminoglycoside drug: the role of copper ions in the determination

Herein, a molecularly imprinted polymer (MIP) was fabricated for specific sensing of an aminoglycoside e.g. kanamycin (KANA). Carbon paste modified with a MIP specific to Cu²⁺-KANA was first introduced. Copper (Cu²⁺) as a metal ion was used as a signal tracer and an amplifier, producing a current response measured by differential pulse voltammetry (DPV). Introducing the aminoglycoside drug into the solution containing Cu²⁺ did not affect the current response of the NIP/CPE. Under the optimum conditions, the as-fabricated sensor exhibited an increase in the current response in the range of 0.55-550 nM with a good limit of detection (LOD, S/N = 3) of 161 pM. The sensor exhibited many advantages including high sensitivity and selectivity, good stability and reproducibility, and cost-effectiveness. Moreover, it was successfully applied for the determination of KANA in milk and honey samples with RSD % not more than 3.3%, suggesting the reliability of the as-designed sensor.

Affinity-Based Analysis Methods for the Detection of Aminoglycoside Antibiotic Residues in Animal-Derived Foods: A Review

With the increasingly serious problem of aminoglycoside antibiotic residues, it is imperative to develop rapid, sensitive and efficient detection methods. This article reviews the detection methods of aminoglycoside antibiotics in animal-derived foods, including enzyme-linked immunosorbent assay, fluorescent immunoassay, chemical immunoassay, affinity sensing assay, lateral flow immunochromatography and molecular imprinted immunoassay. After evaluating the performance of these methods, the advantages and disadvantages were analyzed and compared. Furthermore, development prospects and research trends were proposed and summarized. This review can serve as a basis for further research and provide helpful references and new insights for the analysis of aminoglycoside residues. Accordingly, the in-depth investigation and analysis will certainly make great contributions to food safety, public hygiene and human health.

State of the Art on Developments of (Bio)Sensors and Analytical Methods for Rifamycin Antibiotics Determination

This review summarizes the literature data reported from 2000 up to the present on the development of various electrochemical (voltammetric, amperometric, potentiometric and photoelectrochemical), optical (UV-Vis and IR) and luminescence (chemiluminescence and fluorescence) methods and the corresponding sensors for rifamycin antibiotics analysis. The discussion is focused mainly on the foremost compound of this class of macrocyclic drugs, namely rifampicin (RIF), which is a first-line antituberculosis agent derived from rifampicin SV (RSV). RIF and RSV also have excellent therapeutic action in the treatment of other bacterial infectious diseases. Due to the side-effects (e.g., prevalence of drug-resistant bacteria, hepatotoxicity) of long-term RIF intake, drug monitoring in patients is of real importance in establishing the optimum RIF dose, and therefore, reliable, rapid and simple methods of analysis are required. Based on the studies published on this topic in the last two decades, the sensing principles, some examples of sensors preparation procedures, as well as the performance characteristics (linear range, limits of detection and quantification) of analytical methods for RIF determination, are compared and correlated, critically emphasizing their benefits and limitations. Examples of spectrometric and electrochemical investigations of RIF interaction with biologically important molecules are also presented.

Recent Trends in the Development of Carbon-Based Electrodes Modified with Molecularly Imprinted Polymers for Antibiotic Electroanalysis

Antibiotics are antibacterial agents applied in human and veterinary medicine. They are also employed to stimulate the growth of food-producing animals. Despite their benefits, the uncontrolled use of antibiotics results in serious problems, and therefore their concentration levels in different foods as well as in environmental samples were regulated. As a consequence, there is an increasing demand for the development of sensitive and selective analytical tools for antibiotic reliable and rapid detection. These requirements are accomplished by the combination of simple, cost-effective and affordable electroanalytical methods with molecularly imprinted polymers (MIPs) with high recognition specificity, based on their “lock and key” working principle, used to modify the electrode surface, which is the “heart” of any electrochemical device. This review presents a comprehensive overview of MIP-modified carbon-based electrodes developed in recent years for antibiotic detection. The MIP preparation and electrode modification procedures, along with the performance characteristics of sensors and analytical methods, as well as the applications for the antibiotics’ quantification from different matrices (pharmaceutical, biological, food and environmental samples), are discussed. The information provided by this review can inspire researchers to go deeper into the field of MIP-modified sensors and to develop efficient means for reliable antibiotic determination.