Development of an ultraperformance liquid chromatography method for improved determination of additives in polymeric materials

Trace analysis of multiple synthetic phenolic antioxidants in foods by liquid chromatography-tandem mass spectrometry with complementary use of electrospray ionization and atmospheric pressure chemical ionization

This study presented a universal LC-MS/MS method for trace analysis of multiple synthetic phenolic antioxidants (SPAs) in foods by complementary use of electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI). The analytes included not only the well-known BHT and BHA but also 18 high molecular weight SPAs. The method utilized APCI to achieve sensitive analysis of BHT, Irganox 1010, Irganox 330, and Irganox 3125 based on the finding that APCI significantly improved the sensitivity of these weakly acidic or slightly polar SPAs, and utilized ESI to obtain sensitive analysis of other SPAs. Additionally, the method avoided background contamination by using effective measures including installation of a trapping column in the LC system. Method performance assessment showed satisfactory sensitivity, linearity, accuracy, and precision for analysis of SPAs in vegetable oil, milk powder, and baby fruit puree. Method application revealed widespread contamination of foods with BHT, Irganox 1010, and Irganox 1076.

Quantitative Analysis of Food Additives in a Beverage using High Performance Liquid Chromatography and Diode Array Detection Coupled with Chemometrics

BACKGROUND

In many countries, the levels of synthetic food additives causing harm to humans have been determined and their use has been controlled by legal regulations. Sensitive, accurate and low-cost analysis methods are required for food additive determination.

OBJECTIVE

In this study, a fast high performance liquid chromatography-diode array detection (HPLC-DAD) analytical methodology for quantification of sodium benzoate, potassium sorbate, ponceau 4R, and carmoisine in a beverage was proposed.

METHODS

Partial least squares (PLS) and principal component regression (PCR) multivariate calibration methods applied to chromatograms with overlapped peaks were used to establish a green and smart method with short isocratic elution. A series of synthetic solutions including different concentrations of analytes were used to test the prediction ability of the developed methods.

CONCLUSIONS

The average recoveries for all target analytes were in the range of 98.27-101.37% with average relative prediction errors of less than 3%. The proposed chemometrics-assisted HPLC-DAD methods were implemented to a beverage successfully. Analysis results from sodium benzoate, potassium sorbate, ponceau 4R, and carmoisine in a beverage by PLS-2 and PCR were statistically compared with conventional HPLC.

HIGHLIGHTS

The HPLC methods coupled with the PLS-2 and PCR algorithm could provide a simple, quick and accurate strategy for simultaneous determination of sodium benzoate, potassium sorbate, ponceau 4R, and carmoisine in a beverage sample.

Extraction of Illegal Dyes from Red Chili Peppers with Cholinium-Based Deep Eutectic Solvents

Deep eutectic solvents (DESs) as a new kind of green solvents have been used to extract bioactive compounds but there are few applications in extracting chrysoidine dyes. In this study, we developed an ultrasonic-assisted extraction method with choline chloride/hydrogen bond donor (ChCl/HBD) DES for the extraction of chrysoidine G (COG), astrazon orange G (AOG), and astrazon orange R (AOR) in food samples. Some experimental parameters, such as extraction time, raw material/solvent ratio, and temperature, were evaluated and optimized as follows: the ratio of ChCl/HBD, 1 : 2 (v/v); the ratio of sample/DES, 1 : 10 (g/mL); extraction time, 20 min; extraction temperature, 50°C. Under the optimized conditions, the limits of detection (μg/mL) were 0.10 for COG and 0.06 for AOG and AOR. The relative standard deviations were in the range of 1.2-2.1%. The recoveries of the three dyes were in the range of 80.2-105.0%. By comparing with other commonly used solvents for extracting chrysoidine dyes, the advantages of DESs proved them to be potential extraction solvents for chrysoidine G, astrazon orange G, and astrazon orange R in foods.

Development and Validation of HPLC Method for the Simultaneous Determination of Five Food Additives and Caffeine in Soft Drinks

Box-Behnken design was applied to optimize high performance liquid chromatography (HPLC) conditions for the simultaneous determination of potassium sorbate, sodium benzoate, carmoisine, allura red, ponceau 4R, and caffeine in commercial soft drinks. The experimental variables chosen were pH (6.0–7.0), flow rate (1.0–1.4 mL/min), and mobile phase ratio (85–95% acetate buffer). Resolution values of all peak pairs were used as a response. Stationary phase was Inertsil OctaDecylSilane- (ODS-) 3V reverse phase column (250 × 4.6 mm, 5 μm) dimensions. The detection was performed at 230 nm. Optimal values were found 6.0 pH, 1.0 mL/min flow rate, and 95% mobile phase ratio for the method which was validated by calculating the linearity (r² > 0.9962), accuracy (recoveries ≥ 95.75%), precision (intraday variation ≤ 1.923%, interday variation ≤ 1.950%), limits of detection (LODs), and limits of quantification (LOQs) parameters. LODs and LOQs for analytes were in the range of 0.10–0.19 μg/mL and 0.33–0.63 μg/mL, respectively. The proposed method was applied successfully for the simultaneous determination of the mixtures of five food additives and caffeine in soft drinks.

Screening of additives in plastics with high resolution time-of-flight mass spectrometry and different ionization sources: direct probe injection (DIP)-APCI, LC-APCI, and LC-ion booster ESI

Plastics are complex mixtures consisting of a polymer and additives with different physico-chemical properties. We developed a broad screening method to elucidate the nature of compounds present in plastics used in electrical/electronic equipment commonly found at homes (e.g., electrical adaptors, computer casings, heaters). The analysis was done by (a) solvent extraction followed by liquid chromatography coupled to high accuracy/resolution time-of-flight mass spectrometry (TOFMS) with different ionization sources or (b) direct analysis of the solid by ambient mass spectrometry high accuracy/resolution TOFMS. The different ionization methods showed different selectivity and sensitivity for the different compound classes and were complementary. A variety of antioxidants, phthalates, UV filters, and flame retardants were found in most samples. Furthermore, some recently reported impurities or degradation products derived from flame retardants were identified, such as hydroxylated triphenyl phosphate and tetrabromobisphenol A monoglycidyl ether.

Graphical abstract

Determination of polyolefin additives by reversed-phase liquid chromatography

This article examines the contribution of liquid chromatography to the study of polyolefin additives commonly used to obtain improved environmental resistance (antioxidants, ultraviolet light stabilizers, antistatics, and so on) and appearance enhancements (e.g. colorants). Several reversed-phase liquid chromatographic methods are summarized, and a detailed description of different detectors is provided. In addition, ways of applying these methods to analyse food contact materials and plastic toys are emphasized. Finally, the potential use of these methods is addressed which complies with European health safety regulations.