Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry

Reusable, Green, Portable Ionogels Based on Terpyridine-Imidazole Salt for Visual Monitoring of Pork Spoilage

Ionogels have emerged as a promising approach because they combine the advantageous properties of ionic liquids and gels. Herein, a novel gelator bearing terpyridine and imidazolium salt units was designed and synthesized, which assembled into ionogels in three ionic liquids by a heating-cooling procedure. The properties of ionogels were characterized by FT-IR, UV-vis spectroscopy, POM, XRD, and rheology, and resonance light scattering and opacity measurements were conducted to investigate the gelation kinetics. Furthermore, the ionogels incorporating pH-sensitive dyes (BTB and MR) were exploited as colorimetric sensor to monitor total volatile basic nitrogen (TVB-N) of meat at -4 °C, which can easily and reliably estimate the quality of meat by naked eye recognition, and the results demonstrated a positive correlation between the color variation and TVB-N levels. Notably, the hydrophobic ionogel indicators are more suitable for potential application at high humidity thanks to their antiswelling advantage, which could prevent the inaccurate information produced by hydrogel indicators. In addition, the ionogels could be reused up to three times as colorimetric indicators, suggesting potential applications and competitiveness. Our research sheds new light on the novel application of ionogels in the food industry.

A new approach for analysing biogenic amines in meat samples: Microwave-assisted derivatisation using 2-chloro-3-nitropyridine

Biogenic amines are compounds whose occurrence in meat is linked to the presence of undesirable microorganisms. They can be utilised as a means to assess the quality and purity of the raw material. Therefore, the methods used to determine their levels are crucial in ensuring meat safety. We propose 2-chloro-3-nitropyridine as a new reagent for microwave-assisted synthesis of biogenic amine derivatives. The obtained products were synthesised with high purity and yield and characterised using 1H and 13C NMR as well as high-resolution mass spectrometry. The proposed derivatisation procedure, coupled with the HPLC method, was applied to determine the levels of biogenic amines in sirloin, ham, and chicken breast samples. Furthermore, differences in the content of the aforementioned compounds in the meat samples were analysed after storage for 24 and 72 h. The results suggest that cadaverine can be considered the primary indicator of meat changes, regardless of its type.

Ultrasonic-microwave synergistic supramolecular solvent liquid-liquid microextraction of trace biogenic amines in fish and beer based on solidification of floating organic droplet

It is important to detect the presence of biogenic amines (BAs) as indicators of food freshness. The purpose of this study was to develop a novel ultrasonic-microwave synergistic supramolecular solvent liquid-liquid microextraction based on solidification of floating organic droplet (UMS-SUPRAS-SFO-LLME) combined with high-performance liquid chromatography for the determination of BAs. The physical properties and microstructure of SUPRAS based on 1-dodecanol and tetrahydrofuran were studied, and the extraction conditions such as the SUPRAS volume, the UMS process, and the centrifugal conditions were optimized. The results for the extraction kinetics and thermodynamics showed that UMS-SUPRAS-SFO-LLME is a spontaneous, endothermic diffusion process. The linear ranges of this method are 0.1-2.0 × 105 ng·mL-1 (R2 > 0.994), the limits of detection are 4.0 × 10-3-6.0 × 10-2 ng·mL-1, and the recoveries were 96.28-103.15%. Compared with existing analysis methods, UMS-SUPRAS-SFO-LLME is a sensitive, green and economical sample pretreatment method for analyzing the enrichment of BAs in beer and fish.

Determination of cefuroxime in breast milk by LC-MS/MS using SALLME technique

The World Health Organization recommends that infants be exclusively breastfed for the first 6 months. Antibiotics are among the most commonly prescribed drugs for pregnant and lactating women. The vast majority of drugs pass into breast milk, which may create a risk for the infant. In cases where drug exposure may pose a risk, breastfeeding should be discontinued. Therefore, the mother's drug use should be decided by considering the most accurate and recent data. Cefuroxime is a second-generation cephalosporin antibiotic with a broad spectrum of activity against Gram-negative and -positive microorganisms. In this study, we aimed to develop the LC-MS/MS method using salt-assisted liquid-liquid micro-extraction (SALLME) for the determination of cefuroxime in breast milk. The method was validated according to the European Medicines Agency (EMA) guidelines. Cefuroxime and the internal standard cefixime were extracted from plasma by a SALLME technique. The results obtained from the entire validation study are at an acceptable level according to the EMA criteria. The calibration curve of cefuroxime was between 25 and 1000 ng/ml, with correlation coefficients of >0.99. The lower limit of quantitation was 25 ng/ml for cefuroxime. Furthermore, the developed method was applied for the determination of cefuroxime in real patient breast milk.

Ratiometric SERS aptasensing for simultaneous quantitative detection of histamine and tyramine in fishes

Herein, a SiO₂@Ag NPs core/shell nanoparticles were synthesized to fabricate a surface-enhanced Raman spectroscopy (SERS) sensor for the simultaneous determination of histamine (HIS) and tyramine (TYR) based on specific aptamer recognition and ratiometric strategy. SiO₂@Ag NPs with 4-thiosaminophenol (4-ATP) and Nile blue A (NBA) molecules were used as an internal standard (IS) and labeled with aptamers corresponding to HIS and TYR, respectively. Raman reporter molecules ROX and Cy5 labeled complementary DNA (cDNA) were then hybridized with aptamers to form rigid double-stranded DNA. After the HIS and TYR were captured by their aptamers, resulting in the dissociation of cDNA and separated from the SERS substrate. Therefore, the SERS signal intensity at 1503 cm^-1 of ROX and 1358 cm^-1 of Cy5 tagged on the terminal of cDNA decreased with the concentration of HIS and TYR increasing, while the SERS signal intensity at 1079 cm^-1 of 4-APT and 592 cm^-1 of NBA on the substrate remain stable. Thus, the concentrations of HIS and TYR can be determined by the I₁₅₀₃/I₁₀₇₉ and I₁₃₅₈/I₅₉₂ values, respectively. This sensing strategy achieves a lower detection limit of 0.2 ng/mL for HIS and 0.05 ng/mL for TYR, respectively, demonstrating promising applications in sensitive detection of BAs in animal-derived foodstuff.

Simple analytical method for total biogenic amines content determination in wine using a smartphone

A simple, fast, and green smartphone-based procedure for total biogenic amines content determination in wine was developed and validated. Sample preparation and analysis were simplified to make the method suitable for routine analyses even in resource-scarce settings. The commercially available S0378 dye and smartphone-based detection were used for this purpose. The developed method has satisfactory figures of merit for putrescine equivalent determination with R² of 0.9981. The method's greenness was also assessed using the Analytical Greenness Calculator. Samples of Polish wine were analysed to demonstrate the applicability of the developed method. Finally, results obtained with the developed procedure were compared with those previously obtained with GC-MS in order to evaluate the equivalence of the methods.

A novel method for the therapeutic drug monitoring of biperiden in plasma by GC-MS using salt-assisted liquid-liquid microextraction

Biperiden is an anticholinergic agent with central effects. It is used in Parkinson's syndromes and in the treatment of extrapyramidal symptoms that occur with the use of various agents (neuroleptics, antipsychotics). It causes anticholinergic syndrome in high doses. For this reason, therapeutic drug monitoring of biperiden is important. This study, it was aimed to develop a validated GC-MS method for the therapeutic monitoring of biperiden in human plasma. Biperiden and internal standard biperiden-d5 were extracted from plasma using the salt-assisted liquid-liquid extraction method. The method was validated according to the European Medicines Agency (EMA), Bioanalytical method validation guidelines. The lower limit of quantification of the developed method was chosen as 0.5 ng/mL. The calibration curve of biperiden for the method was validated between 0.5 and 15 ng/mL, showing correlation coefficients >0.99. In addition, the developed method was used for the therapeutic drug monitoring of biperiden in real patient plasma.

Hydrophobic Mesoporous Silica-Coated Solid-Phase Microextraction Arrow System for the Determination of Six Biogenic Amines in Pork and Fish

In this study, a functionalized mesoporous silica-coated solid-phase microextraction (SPME) Arrow system was developed for the enrichment of six biogenic amines (BAs) from pork and fish samples before gas chromatographic separation with a mass spectrometer as a detector. MCM-41 was utilized as the substrate material and thereby functionalized by titanate and sodium dodecyl sulfate to adjust its surface acidity and hydrophobicity, respectively. The functionalized MCM-41 (named as MCM-T-H) was coated on a bare SPME Arrow using the dipping method and polyacrylonitrile was used as the adhesive. The extraction capacity and selectivity of the MCM-T-H-SPME Arrow for six kinds of derivatized BAs were studied and compared with commercial SPME Arrows. Experimental parameters, e.g., sample volume, derivatization reagent amount, extraction time, and desorption time, which have a dramatic effect on SPME Arrow pretreatment, were optimized. Acidity enhanced MCM-T-H coating showed a much higher affinity to derivatized BAs compared to a commercial SPME Arrow in terms of extraction capacity. In addition, hydrophobicity modification significantly reduced the interference of water molecules on the interaction between MCM-T-H and the derivatized BAs. The MCM-T-H-SPME Arrow showed efficient separation and enrichment capacity for derivatized BAs from complex matrices and therefore, the sample pretreatment time was saved. According to the experimental results, the optimal condition was to add 10 μL derivatization reagent to a 10 mL sample and maintain an agitation speed of 1250 r min^-1. The MCM-T-H-SPME showed excellent reproducibility (RSD < 9.8%) and fast adsorption kinetics (30 min) and desorption kinetics (5 min) for derivatized BAs under optimal conditions. In summary, the MCM-T-H-SPME Arrow based method was employed for accurate monitoring of the variations of BAs in pork and fish, and good results were achieved.

Utilization of ionic deep eutectic solvent as sustainable mobile phase additive in HPLC for improving the separation of biogenic amines

Biogenic amines are present in large quantities in fermented foods and are a key marker for assessing food safety. This paper proposes a novel method for high-performance liquid chromatography analysis of biogenic amines using deep eutectic solvent as mobile phase additive. After screening eight synthetic deep eutectic solvents and comparing with several common additives, deep eutectic solvents based on choline chloride and ethylene glycol showed significant effects for improving the separation of biogenic amines. A Box-Behnken design of 17 runs was used to screen and optimize the key chromatographic parameters, resulting in an expected composition of the mobile phase of 0.73% deep eutectic solvent, 65% acetonitrile, and a column temperature of 28°C. The proposed method exhibited excellent linearity (0.1-50 μg/mL, R² ≥ 0.9987), limit of detection (0.007-0.031 μg/mL), precision (1.28-5.34%) and accuracy (87.2-110.6%). The method can be applied successfully to the separation and analysis of biogenic amines in cooking wine samples. This article is protected by copyright. All rights reserved.