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1.
Biomed Environ Sci ; 30(1): 52-58, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28245899

RESUMO

We identified and quantified a variety of mineral elements in 18 tobacco samples purchased from a Tunisian market. In total, 25 mineral elements have been measured in cigarettes, water pipe tobacco, and smokeless tobacco using inductively coupled plasma-optical emission spectroscopy following microwave-assisted digestion. Statistical analyses were performed using SPSSTM, version 18.0. The lowest concentrations of all studied elements were observed in water pipe tobacco. Significantly higher concentrations of Al, Fe, Mg, Na, Ca, Cr, and Co were found in smokeless tobacco, while cigarettes brands contained the highest concentrations of K, Mn, Ni, Ba, and Sr. There was no significant difference between the mineral contents of local and foreign cigarettes and conventional and light cigarettes. Our findings demonstrated that local smokeless tobacco appears to be the most hazardous tobacco type. The concentration of minerals in light cigarettes was not significantly different from the concentration in conventional cigarettes.


Assuntos
Elementos Químicos , Nicotiana/química , Tabaco sem Fumaça/análise
2.
J AOAC Int ; 100(6): 1879-1884, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28550677

RESUMO

Children's fast food menus, including hamburgers served with french fries, dessert, and a soft drink, were analyzed to obtain the mineral profile of trace elements. The developed analytical methodology involved sample digestion under pressure inside a microwave oven with a mixture of HNO3 and H2O2 and inductively coupled plasma-optical emission spectrometry. The method was validated by carrying out the analysis of certified reference materials (NIST 1570a spinach leaves, NCS ZC73016 chicken, and NIST 1568a rice flour) and using recovery experiments. Repeatability was verified by analyzing replicate samples. Twenty-six elements were studied, 12 of which-aluminum, barium, calcium, copper, iron, potassium, lithium, magnesium, manganese, sodium, strontium, and zinc-were quantitatively determined. Results were compared with other studies of fast food and children's menus published in the literature, and the nutritional value of samples was assessed with dietary intake guidelines.


Assuntos
Fast Foods/análise , Minerais/análise , Análise Espectral/métodos , Oligoelementos/análise , Adolescente , Calibragem , Criança , Pré-Escolar , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Metais , Micro-Ondas , Análise Espectral/instrumentação
3.
J Forensic Sci ; 60(5): 1199-205, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26260573

RESUMO

There is an increasing demand for herbal medicines in weight loss treatment. Some synthetic chemicals, such as sibutramine (SB), have been detected as adulterants in herbal formulations. In this study, two strategies using near infrared (NIR) spectroscopy have been developed to evaluate potential adulteration of herbal medicines with SB: a qualitative screening approach and a quantitative methodology based on multivariate calibration. Samples were composed by products commercialized as herbal medicines, as well as by laboratory adulterated samples. Spectra were obtained in the range of 14,000-4000 per cm. Using PLS-DA, a correct classification of 100% was achieved for the external validation set. In the quantitative approach, the root mean squares error of prediction (RMSEP), for both PLS and MLR models, was 0.2% w/w. The results prove the potential of NIR spectroscopy and multivariate calibration in quantifying sibutramine in adulterated herbal medicines samples.


Assuntos
Depressores do Apetite/análise , Ciclobutanos/análise , Preparações de Plantas/química , Espectroscopia de Luz Próxima ao Infravermelho , Análise Discriminante , Contaminação de Medicamentos , Modelos Lineares
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