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BACKGROUND: Parabens are esters of p-hydroxybenzoic acid and are widely used as preservatives in cosmetics, pharmaceuticals and foodstuffs. The presences of parabens in infant formulas raise concerns due to their potential to disrupt endocrine function in infants and cause reproductive toxicities. METHODS: In this study a new method was developed for extraction and determination of methylparaben in infant formulas using HPLC method and UV detector. Methanol and trichloroacetic acid were used for extraction and isocratic mobile phase comprising equal proportions of glacial acetic acid in water (50:850 v/v) and methanol was used for separation of methylparaben. RESULTS: Recovery of the extraction procedure was good and interferences between methylparaben and other ingredients peaks in HPLC chromatograms decreased. The average recoveries for methylparaben were about 88-108 %. The limit of detection and limit of quantitation for methylparaben were 0.2 and 0.5 µg/mL, respectively. Results of the method showed good reproducibility (relative standard deviation (RSD) 0.29-1.94 % for within day analysis and 0.84-2.18 % for between day analysis). Results were linear in range of 0.5-20 µg/mL methylparaben. The results of twenty real infant formula samples showed methylparaben was found only in one sample in concentration 0.3 µg/mL. CONCLUSIONS: The new extraction and measurement method was a short-time method and could be applicable for large numbers of samples. This method was fast, sensitive and accurate and was capable of being used in legal laboratory references for determination of methylparaben content.
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BACKGROUND: The adulteration of milk by hazardous chemicals like surfactants has recently increased. It conceals the quality of the product to gain profit. As milk and milk-based products are consumed by many people, novel analytical procedures are needed to detect these adulterants. This study focused on Fourier-transform infrared (FTIR) spectroscopy equipped with an attenuated total reflection (ATR) accessory, and near-infrared (NIR) spectroscopy for the determination of milk-surfactant adulteration using a genetic algorithm (GA) coupled with multivariate methods. The model surfactant was sodium dodecyl sulfate (SDS), and its concentration varied from 1.94-19.4 gkg-1 in adulterated samples. RESULTS: Prominent peaks in the spectral range of 5500-6400 cm-1 , 1160-1260 cm-1 and 1049-1080 cm-1 may correspond to the sulfonate group in SDS. A genetic algorithm could significantly reduce the number of variables to almost one third by selecting the specific wavenumber region. Principal component analysis (PCA) for ATR and NIR data indicated separate clusters of samples in terms of the concentration level of SDS (P ≤ 0.05). Partial least squares regression (PLSR) was used to determine the maximum R2 value for ATR and NIR data for calibration, cross-validation and prediction, which were 0.980, 0.972, 0.980, and 0.970, 0.937, and 0.956 respectively. The results showed apparent differences between unadulterated and adulterated samples using partial least squares-discriminant analysis (PLS-DA), which was validated by the permutation test. CONCLUSION: The results clearly show the successful application of the proposed methods with multivariate analysis in the selection of variables, classification, clustering, and identification of the adulterant in amounts as low as 1.94 gkg-1 in milk. © 2020 Society of Chemical Industry.
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Contaminación de Alimentos/análisis , Leche/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Tensoactivos/análisis , Algoritmos , Animales , Bovinos , Análisis Discriminante , Análisis de los Mínimos Cuadrados , Dodecil Sulfato de Sodio/análisisRESUMEN
Adulteration of olive oil with the other cheap oils and fats plays an important role in economics and has nutritional benefits. In this work, metabolite profiling was performed using gas chromatography-mass spectrometry to identify and quantify animal fat (lard) adulteration in vegetable oil (olive oil). Principal component analysis could correctly identify and clustering olive oil, sunflower oil, sesame oil, lard, and adulterated samples through the changes in their fatty acid methyl esters (FAMEs) profile. A targeted metabolomics method was then optimized and validated through construction of calibration curves of known FAMSs in olive oil and lard. The method was presented high linearity (R2 > 0.96) and good intra and inter day accuracy and precision (79-101 and 86-102% and 2-7 and 3-7, respectively) for determination of FAMEs. Afterwards the absolute concentration and relative percentage of FAMEs were successfully determined in 12 commercial olive oils and 3 lards samples. Methyl myristate, methyl palmitate, methyl oleate, and methyl stearate were selected as discriminant markers to identify and quantify lard adulteration even at a low level of lard (5%w/w), with errors less than 2% in the comparison of the absolute or relative concentrations of FAMEs using several statistical methods. The proposed methodology allowed us to quantify the FAMEs simultaneously and also could predict small amount of lard in the adulterated olive oil samples.
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Human interferons (IFNs) are key cytokines secreted by immune system. They have several effects such as antiviral and anti tumors activity, activating immune cells and healing of multiple sclerosis. The type IFNs present in humans are α ,ß and Υ. IFN ß is a polypeptide, normally produced by fibroblasts and seems to be more species-specific than IFN. Structural properties of IFNs are important for their biologic effects. There are a few analytical techniques for separation, identification and determination of IFNs in its formulations such as mass spectroscopy, RP-HPLC and capillary electrophoresis (CE). In this study we used Micellar Electrokinetic Chromatography (MEKC) as a unique mode of CE because of its capability to separate neutral as well as charged solutes. We used sodium tetraborate (Borax) as buffer without any modifier and sodium dodecyl sulfate (SDS) as surfactant. The optimum MECK running buffer consisted of Borate 50 Mm; SDS 20 mM pH =9.6. The validated method was used for determination of the IFN ß-1b formulation which is manufactured in Iran. From 9 collected different batches, all of them had acceptable potency as claimed on their label with average 102.25 ±10.030 %. This is the first time that a MEKC method is introduced for quantification of IFN ß-1b in its pharmaceutical dosage forms. The method is reliable safe, rapid and accurate.
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INTRODUCTION: The aim of this study was to investigate the relationship between the admission blood glucose level following acute poisoning, severity of acute poisoning and clinical outcome. MATERIAL AND METHODS: This prospective study was conducted on 345 deliberate self-poisoning patients. Standard demographic and clinical information; admission blood glucose level; poisoning severity score and outcome were recorded. Patients with a history of diabetes mellitus, receipt of pre-sampling intravenous dextrose solution or glucocorticoids, and poisoning with toxic agents which produce hyper- or hypoglycaemia were excluded. RESULTS: Mean age of the patients was 27.5 ±8.6 years. Females outnumbered males (57.9%). Oral ingestion of more than one drug (46.7%) and opiates (14.2%) were the main causes of poisoning. Blood glucose values ranged from 50 mg/dl to 396 mg/dl. Hyper- and hypoglycaemia were observed in 23.8% and 13.91% respectively. A total of 24.41% and 22.92% of the patients in hyper- and hypoglycaemic groups had grade 3 and 4 severity score in comparison with 4.18% in the normoglycaemic group. Development of complications and death were 14.64% and 10.42% in patients with hyper- and hypoglycaemia versus 3.73% in patients with normoglycaemia. A significant difference between normoglycaemic and hyperglycaemic patients in the severity of poisoning and clinical outcome was observed (P < 0.001). CONCLUSIONS: Admission blood glucose levels may have a relationship with the severity of poisoning and clinical outcome following acute poisoning.