A rapid and reliable assay to determine flumequine, marbofloxacin, difloxacin, and sarafloxacin in commonly consumed meat by micellar liquid chromatography

Detection of ciprofloxacin and pH by carbon dots and rapid, visual sensing analysis

Food safety is a serious issue worldwide and practical detection method is vital for the supervision of food safety. It is necessary to establish efficient and economical methods to detect antibiotics, especially antibiotics in complex systems. This study employs citric acid and m-phenylenediamine to synthesize N, P-codoped carbon dots (N, P-CDs) by a microwave-assisted method. Anhydrous ethanol and phosphoric acid are essential to the properties of N, P-CDs. A "turn-on" fluorescent probe based on N, P-CDs was established for detecting ciprofloxacin (CIP) with detection limit down to 24.2 nm. Semiquantitative test stripe and a PS color detection system for CIP were developed to achieve visual and smart detection. The test stripe is applied to the visual detection of CIP residues in milk and a popular Chinese cuisine, Malatang, for the first time. N, P-CDs can also be used to detect pH in the range of pH 7.5-12.

A chemiluminescence method based on Ce-PA-Tb polymer for rapid determination of difloxacin in aquatic products

Ce-PA-Tb polymer with Ce and Tb as metal ion centers was prepared and applied in chemiluminescence (CL) reaction. The structure and property of Ce-PA-Tb were explored. Ce-PA-Tb combines both the oxidant ion (Ce(IV)) and luminescence ion (Tb(III)). Difloxacin can enhance the CL signal of Ce-PA-Tb-SO32- reaction in acidic medium. Under the optimized affecting factors, a CL method for the selective difloxacin determination was established. The CL intensity showed a good linear relationship from 10.0 to 300.0 μg/L (r = 0.9996) with the limit of detection was 1.1 μg/L. The method with the signal response at 0.5 s and completed the CL process within 10 s. The method was used to determine difloxacin in aquatic products, and the recovery rate was in the range of 88.1%-104.0%. The CL method designed Ce-PA-Tb based is demonstrated to be an excellent tool for difloxacin determination in aquatic products.

Flumequine-mediated fluorescent zeolitic imidazolate framework functionalized by Eu3+ for sensitive and selective detection of UO22+, Ni2+ and Cu2+ in nuclear wastewater

Currently, antibiotics and heavy metal contaminants have posed a great threat for ecological security and human health. Herein, the lanthanide functionalized ZIF (named ZIF-90-PABA-Eu) is constructed by coordinating with Eu³⁺ via p-aminobenzoic acid intermediate. Due to the excellent fluorescence properties, the novel fluorescent probe can selectively monitor flumequine based on "turn on" mode. Furthermore, the obtained new material (named ZIF-90-PABA-Eu-Flu) can be used as "turn off" sensor for selective detection of both radioactive and nonradioactive heavy metal ions (UO₂²⁺, Ni²⁺ and Cu²⁺) which are the main component of nuclear industrial wastewater. ZIF-90-PABA-Eu-Flu shows ultra-short fluorescence response time (3 s) and ultra-low limit of detection (9.0 × 10^-3, 1.3 × 10^-2 and 6.1 × 10^-4 ppm) for three metal ions, which may be attributed to its good affinity with UO₂²⁺, Ni²⁺ and Cu²⁺. Moreover, principal component analysis (PCA) is applied to distinguish the three metal ions. Additionally, the possible sensing mechanism is investigated by the UV-vis spectra, luminescence lifetimes and theoretical calculation analysis. Based on these results, ZIF-90-PABA-Eu possesses promising potential in practical application and provides insight for the design of novel probes to continuously monitor flumequine, radioactive and nonradioactive heavy metal ions.

Determination of six drugs used for treatment of common cold by micellar liquid chromatography

The use of organic solvents as eluants in RP-HPLC has an important role to decrease retention time and improve peak shape; however, it has high environmental impacts. Their production and disposal represent economic and biohazard problems. So, alternatives had to be introduced and studied to minimize such pollution. Combination of sodium dodecyl sulfate (SDS) together with polyoxyethylene-23-lauryl ether (Brij-35) was studied as an alternative to the presence of organic solvents on the separation performance of six active pharmaceutical ingredients. Response surface methodology was applied to test the impact of three independent variables; concentrations of SDS and Brij-35, as well as, pH of the mobile phase; on retention, peak symmetry, and resolution of the analytes using a rotatable central composite design. Significant variables were determined and the suggested models for predicting retention and resolution parameters were significant. Meanwhile, the common cold is the most abundant disease treated with over-the-counter (OTC) medications worldwide. In 2015, the USA recorded $9.56 billion total sales of OTC cold and cough medicaments alone, with average individual patient expenditure of $338. The worldwide sales and generics of common cold and cough products keep growing annually. The six active pharmaceutical molecules under study, namely, paracetamol, guaifenesin, pseudoephedrine, ibuprofen, chlorpheniramine, and dextromethorphan, are widely used in common cold products. The predicted optimum conditions were validated using mobile phase consisting of 93.6 mM SDS, 32.0 mM Brij-35, and 10.0 mM sodium dihydrogen phosphate, adjusted at pH 5.2, column temperature 35° C, and detection at 215-nm wavelength. The method was successfully applied to determine 12 different combination formulae of the analytes in their pharmaceutical products and was assessed for greenness on two novel metrics. A thorough comparison to previously reported methods was included and methods were assessed against greenness metrics Green Analytical Procedure Index and Analytical Greenness Metric to demonstrate superiority.

Analytical capabilities of micellar liquid chromatography and application to residue and contaminant analysis: A review

Green chemistry is the use of chemistry to reduce or eliminate the use of generation of feedstocks, products, by-products, solvents, reagents, etc. that are hazardous to human health or the environment. One of the branches of green chemistry is micellar liquid chromatography. Micellar liquid chromatography is a reversed-phase liquid chromatographic mode with mobile phases containing a surfactant above its critical micellar concentration. The applications of micellar liquid chromatography for the determination of numerous compounds in pharmaceutical formulation, biological samples, food, environmental samples, and feeds have been growing rapidly. Micellar liquid chromatography technique has several advantages over other chromatographic techniques. Its main advantage is the small amount of organic modifiers used such as acetonitrile and methanol and the safety and recyclability of the mobile phase. In our work, we discuss the development of "green chemistry" and present what micellar liquid chromatography is. This article presents application methods with the use of micellar liquid chromatography for analysis on antibacterial substances, melamine, biogenic amines, plant protection products, flavonoids, as well as peptides in biological matrices such as milk, eggs, tissues, honey, and feed.

Determination of antibiotics in meat samples using analytical methodologies: A review

Antibiotics are widely used to prevent or treat some diseases in human and veterinary medicine and also as animal growth promoters. The presence of these compounds in foods derived from food-producing animals can be a risk for human health. Consequently, regulatory agencies have set maximum residue limits for antibiotics in food samples. Therefore, the development of novel methodologies for its determination in food samples is required. Specifically, the analysis and quantification of these substances in meat tissues is a challenge for the analytical chemistry research community. This is due to the complexity of the matrix and the low detection limits required by the regulatory agencies. In this sense, a comprehensive review on the development of new sample preparation treatments involving extraction, cleanup, and enrichment steps of antibiotics in meat samples in combination with sensitive and sophisticated determination techniques that have been carry out in the last years is necessary. Therefore, the aim of this work is to summarize the published methodologies for the determination of antibiotics from 2016 until the beginning of the second semester of 2020. The first part of this review includes an introduction about antibiotic families, followed by sample preparation and determination techniques applied to the different families. Finally, a detailed discussion of the current trends and the future possible perspectives in this field are also included.

A turn-on fluorescence sensing strategy for rapid detection of flumequine in water environments using covalent-coordination functionalized MOFs

With high output and large use of antibiotics in the process of aquaculture, pollution caused by antibiotics in water environments is becoming a thorny problem, and its ecological risk has aroused widespread concern.

Solvent-free mixed micellar mobile phases: An advanced green chemistry approach for reversed-phase HPLC determination of some antihypertensive drugs

Minimizing the amount of organic solvents without loss in chromatographic performance has been an important step toward greening analytical methodologies. Mobile-phase composition is the key for maintaining separation efficiency in liquid chromatography while decreasing the procedure hazardousness. If sodium dodecyl sulfate is mixed with Brij-35 in the mobile phase, they could be used as a green alternative for using organic modifiers. In this research, the effect of changing the relative amounts of both surfactants was studied on the chromatographic performance and separation efficiency of ten antihypertensive drugs belonging to different categories. The use of surfactants has many advantages including low cost and toxicity, safe environmental disposal, unique selectivity besides high solubilization capabilities. The optimum separation was maintained using a mobile phase (0.01 M Brij-35, 0.08 M sodium dodecyl sulfate and 0.01 M sodium dihydrogen phosphate/pH 5) on reversed-phase C18 core-shell column at flow rate 1.5 mL/min and temperature 30°C. The method was successfully applied for the determination of the drugs in various marketed dosage forms. International Conference of Harmonization guidelines were followed to validate the developed method. Additionally, the method was verified on the Green Analytical Procedure Index in regards to the greenness and found to be an excellent green alternative method.

Use of Micellar Liquid Chromatography to Determine Mebendazole in Dairy Products and Breeding Waste from Bovine Animals

Mebendazole is an anthelmintic drug used in cattle production. However, residues may occur in produced food and in excretions, jeopardizing population health. A method based on micellar liquid chromatography (MLC) was developed to determine mebendazole in dairy products (milk, cheese, butter, and curd) and nitrogenous waste (urine and dung) from bovine animals. Sample treatment was expedited to simple dilution or solid-to-liquid extraction, followed by filtration and direct injection of the obtained solution. The analyte was resolved from matrix compounds in less than 8 min, using a C18 column and a mobile phase made up of 0.15 M sodium dodecyl sulfate (SDS)–6% 1-pentanol phosphate buffered at pH 7, and running at 1 mL/min under isocratic mode. Detection was performed by absorbance at 292 nm. The procedure was validated according to the guidelines of the EU Commission Decision 2002/657/EC in terms of: specificity, method calibration range (from the limit of quantification to 25–50 ppm), sensitivity (limit of detection 0.1–0.2 ppm; limit of quantification, 0.3–0.6 ppm), trueness (92.5–102.3%), precision (<7.5%, expressed at RSD), robustness, and stability. The method is reliable, sensitive, easy-to-handle, eco-friendly, safe, inexpensive, and provides a high sample-throughput. Therefore, it is useful for routine analysis as a screening or quantification method in a laboratory for drug-residue control.

Procedure for the Screening of Eggs and Egg Products to Detect Oxolonic Acid, Ciprofloxacin, Enrofloxacin, and Sarafloxacin Using Micellar Liquid Chromatography

A method based on micellar liquid chromatography was developed to determine oxolinic acid, ciprofloxacin, enrofloxacin, and sarafloxacin in eggs and egg products. The antimicrobial drugs were obtained in a micellar solution which was directly injected. The analytes were resolved using a C18 column and a mobile phase of 0.05 M sodium dodecyl sulfate—7.5% 1-propanol—0.5% triethylamine, buffered at pH 3 with phosphate salt, running under the isocratic mode. The signal was monitored by fluorescence. Validation was successfully performed according to the EU Commission Decision 2002/657/EC in terms of specificity, calibration range (LOQ to 1 mg/kg), linearity (R² > 0.9991), limit of detection and decision limit (0.01–0.05 mg/kg), limit of quantification (0.025–0.150 mg/kg), detection capability (<0.4 times decision limit), trueness (−14.2% to +9.8%), precision (<14.0%), robustness, and stability. The procedure was environmentally friendly, safe, easy-to-conduct, inexpensive, and had a high sample throughput, thus it is useful for routine analysis as a screening method in a laboratory for food residue control.