Application of constrained mixture design and Doehlert matrix in the optimization of dispersive liquid-liquid microextraction assisted by ultrasound for preconcentration and determination of cadmium in sediment and water samples by FAAS

Meira, Lucília A.; Dias, Fábio de S.

doi:10.1016/j.microc.2016.07.013

Cited by 54 publications

(4 citation statements)

References 36 publications

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“…These small changes are represented by any variation in the nominal values of the proposed original procedure parameters. Because the robustness can be tested through multivariate methodologies, the optimal values were used as the central point and a small variation was made in these values, according to the conditions described in Section 2.4. A complete factorial design 2 3 (Table ), involving the variables time of sonication, NaOH concentration, and amplitude of sonication was performed.…”

Section: Resultsmentioning

confidence: 99%

Multiple response optimization of alkaline pretreatment of sisal fiber (Agave sisalana) assisted by ultrasound

Brito

Dias

Cunha

et al. 2019

Biotechnology Progress

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A procedure for the alkaline pretreatment of sisal fiber assisted by ultrasound was optimized to obtain a higher solubilization of hemicellulose and the removal of lignin with cellulose fraction maintenance. A full factorial design 2 3 was used for the evaluation of the effects of the variables (sonication time, NaOH concentration, and sonication amplitude) on the pretreatment. The optimal values for the variables using the Doehlert matrix for the sonication time, NaOH concentration, and sonication amplitude were 27 min, 4.1% (m/v), and 50%, respectively. The X-ray diffractometry and scanning electron microscopy analyses, after pretreatment, showed changes in chemical structure and morphology due to the removal of 82% of hemicellulose and 86% of lignin from sisal fiber. The soft reaction conditions and relatively short times demonstrated the effectiveness of the combined action of ultrasound with alkaline pretreatment to improve the accessibility to cellulose in this important step of the ethanol production process from biomass. K E Y W O R D SAlgave sisalana, alkaline treatment, biomass, multiple response optimization, second generation ethanol, ultrasound energy

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Section: Resultsmentioning

confidence: 99%

Multiple response optimization of alkaline pretreatment of sisal fiber (Agave sisalana) assisted by ultrasound

Brito

Dias

Cunha

et al. 2019

Biotechnology Progress

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“…For humans, Alzheimer, Parkinson, and Itai-itai are infamous Cdinduced diseases. Osteoporosis, renal dysfunction, and bladder cancer have also been reported to be induced by Cd (Akesson et al, 2008;Feki-Tounsi and Hamza-Chafai, 2014;Meira and Dias, 2017). Cd is also known to inhibit macroalgae's typical growth and photosynthetic function.…”

Section: Discussionmentioning

confidence: 99%

Mechanism of macroalgae Gracilaria bailiniae responding to cadmium and lanthanum

et al. 2022

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Macroalgae can accumulate a wide array of metals, leading to their appliance as biomonitors of aquatic environments. With the rapid development of industrial and agricultural-based activities, Cd pollution in aquatic environments is considered an increasingly severe problem worldwide. Although La could alleviate the Cd stress in higher terrestrial plants, the response mechanisms of macroalgae to Cd and La are unknown. Along these lines, in this work, Cd significantly affected the growth, internal cellular structure, photosynthesis, pigment content, antioxidant enzyme activity, and lipid peroxidation level of G. bailiniae. However, the presence of La alleviated these adverse effects from Cd. Furthermore, the response mechanism of G. bailiniae to Cd was attributed to the self-antioxidant ability enhancement, membrane defense, and programmed-cellular regulation. However, the presence of La mediated the biosynthesis of both flavonoids and lipids, which inhibited the Cd accumulation, modulated algal stress signalling networks, renewed the impaired chlorophyll molecule, maintained the activity of the crucial enzyme, enhanced antioxidant ability, and maintained the stabilization of redox homeostasis, alleviating the adverse impact from Cd and improve the growth of G. bailiniae. The experimental results successfully demonstrate a new detoxicant to alleviate Cd stress, promoting a more comprehensive array of macroalgal applications.

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“…During the emulsion breaking,the aqueous layer is isolated from the oily phase via either heatingor centrifugation, and the analyte is released to the aqueous phase (Moreira and de Souza Dias, 2018), (Carneiro et al, 2020). This procedure has proved to be more efficient, fatser, simpler and moretrustworthyin comparison with the other previously reported methods (Meira and de Souza Dias, 2017).…”

Section: Introductionmentioning

confidence: 93%

Development Method for The Determination of Cr, Cd And Pb in Edible Sunflower Oil Using Emulsion Extraction-faas

2023

UOD

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The presence of heavy metals in vegetable oils has negative health effects when consumed by living organisms. As a result, assessing mineral extraction methods is critical for monitoring mineral concentration levels and ensuring oil quality. This study describes a new analytical method for the determination of cadmium (Cd), chromium (Cr), and lead (Pb) in edible sunflower oil using emulsion extraction followed by flame atomic absorption spectroscopy (FAAS). The method is based on the formation of a water-in-oil emulsion by mixing the oil sample with (1, 10 -2 and 10 -3 M nitric acid solution for Pb, Cr, and Cd respectively) incorporated with a certain amount of a surfactant Triton-X 100 for Pb and Cr, and Tween 80 for Cd. Once the emulsion was formed, it was broken by centrifuging the mixture at 4000 rpm for 5 minutes. This led to the extraction of metal ions into the aqueous phase which was collected, and introduced to FAAS for metal analysis. Neither an organic solvent was used nor an additional dilution was performed prior to the metal analysis. Various parameters that may affect the extraction efficiency of the target metals were evaluated and optimized. The detection limits were 20.0 μg/kg for lead, 4.0 μg/kg for chromium, and 0.2 μg/kg for cadmium. The standard addition method was used for the construction of the calibration curve to mitigate the potential interferences caused by the sample matrix. The findings confirmed that the proposed sample preparation method combined with FAAS provides a simple and reliable analytical method for the measurement of lead, chromium, and cadmium in edible oils.

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Application of constrained mixture design and Doehlert matrix in the optimization of dispersive liquid-liquid microextraction assisted by ultrasound for preconcentration and determination of cadmium in sediment and water samples by FAAS

Cited by 54 publications

References 36 publications

Multiple response optimization of alkaline pretreatment of sisal fiber (Agave sisalana) assisted by ultrasound

Multiple response optimization of alkaline pretreatment of sisal fiber (Agave sisalana) assisted by ultrasound

Mechanism of macroalgae Gracilaria bailiniae responding to cadmium and lanthanum

Development Method for The Determination of Cr, Cd And Pb in Edible Sunflower Oil Using Emulsion Extraction-faas

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