Niobium oxide prepared by sol–gel using powder coconut water

Lucas, José M.F.; Teixeira, S. Soreto; Gavinho, Sílvia Rodrigues; Prezas, P.R.; Silva, C. C.; Sales, A. J. M.; Almeida, Ana Fabíola Leite; Freire, Francisco Nivaldo Aguiar; Salgueiro, Cristiane Clemente de Mello; Nunes, J. F.; Graça, M.P.F.

doi:10.1007/s10854-019-01482-y

Cited by 8 publications

(3 citation statements)

References 41 publications

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“…This evidence is certainly related to the lithium ferrite synthesis route, once the powder of coconut water has a very rich composition in carbohydrates, amino acids, vitamins, proteins, and minerals, potassium being one of the major mineral constituents. In the mineral composition, potassium is the major constituent [ 59 ]. Given that EDS just detects elements with an atomic number higher than 5, only the automatic search was made including the elements with an atomic number higher than that.…”

Section: Resultsmentioning

confidence: 99%

Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine

et al. 2021

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The physical properties of the cubic and ferrimagnetic spinel ferrite LiFe5O8 has made it an attractive material for electronic and medical applications. In this work, LiFe5O8 nanosized crystallites were synthesized by a novel and eco-friendly sol-gel process, by using powder coconut water as a mediated reaction medium. The dried powders were heat-treated (HT) at temperatures between 400 and 1000 °C, and their structure, morphology, electrical and magnetic characteristics, cytotoxicity, and magnetic hyperthermia assays were performed. The heat treatment of the LiFe5O8 powder tunes the crystallite sizes between 50 nm and 200 nm. When increasing the temperature of the HT, secondary phases start to form. The dielectric analysis revealed, at 300 K and 10 kHz, an increase of ε′ (≈10 up to ≈14) with a tanδ almost constant (≈0.3) with the increase of the HT temperature. The cytotoxicity results reveal, for concentrations below 2.5 mg/mL, that all samples have a non-cytotoxicity property. The sample heat-treated at 1000 °C, which revealed hysteresis and magnetic saturation of 73 emu g−1 at 300 K, showed a heating profile adequate for magnetic hyperthermia applications, showing the potential for biomedical applications.

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Section: Resultsmentioning

confidence: 99%

Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine

et al. 2021

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“…These particles were synthesized with a novel sol-gel method through a proteic route using metal nitrates as raw materials. Powdered coconut water (PCW) was used as a precursor, respecting green chemistry principles, such as the prevention of waste, as very little was created in the synthesis; the use of less hazardous chemicals; and the use of a renewable precursor (PCW), turning this method into an eco-friendly route [ 11 ], as opposed to other routes that use ethylene glycol and citric acid [ 12 , 13 , 14 ]. This method has already been used in the synthesis of nanoparticles and ceramic materials, such as BaFe 12 O 19 [ 15 ] and SrFe 12 O 19 [ 16 ].…”

Section: Introductionmentioning

confidence: 99%

Potassium Ferrite for Biomedical Applications

et al. 2023

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Ferrites have been widely studied for their use in the biomedical area, mostly due to their magnetic properties, which gives them the potential to be used in diagnostics, drug delivery, and in treatment with magnetic hyperthermia, for example. In this work, KFeO2 particles were synthesized with a proteic sol-gel method using powdered coconut water as a precursor; this method is based on the principles of green chemistry. To improve its properties, the base powder obtained was subjected to multiple heat treatments at temperatures between 350 and 1300 °C. The samples obtained underwent structural, morphological, biocompatibility, and magnetic characterization. The results show that upon raising the heat treatment temperature, not only is the wanted phase detected, but also the secondary phases. To overcome these secondary phases, several different heat treatments were carried out. Using scanning electron microscopy, grains in the micrometric range were observed. Saturation magnetizations between 15.5 and 24.1 emu/g were observed for the samples containing KFeO2 with an applied field of 50 kOe at 300 K. From cellular compatibility (cytotoxicity) assays, for concentrations up to 5 mg/mL, only the samples treated at 350 °C were cytotoxic. However, the samples containing KFeO2, while being biocompatible, had low specific absorption rates (1.55–5.76 W/g).

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“…According to the necessity of employing green synthesis methods in science, PCW was chosen as the precursor for the sol-gel reaction. Consisting of a rich composition of sugar, amino acids, and minerals, this compound acts as a surfactant for the reaction [5,20]. This approach has been employed previously for the synthesis of nanoparticles such as BaFe 12 O 19 [21], SrFe 12 O 19 [22], KfeO 2 [23], and SrAl 2 O 4 [24].…”

Section: Introductionmentioning

confidence: 99%

Cobalt Ferrite Synthesized Using a Biogenic Sol–Gel Method for Biomedical Applications

Gomes,

Costa,

Carvalho

et al. 2023

Molecules

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Cancer is one of the leading causes of death worldwide. Conventional treatments such as surgery, chemotherapy, and radiotherapy have limitations and severe side effects. Magnetic hyperthermia (MH) is an alternative method that can be used alone or in conjunction with chemotherapy or radiotherapy to treat cancer. Cobalt ferrite particles were synthesized using an innovative biogenic sol–gel method with powder of coconut water (PCW). The obtained powders were subjected to heat treatments between 500 °C and 1100 °C. Subsequently, they were characterized by thermal, structural, magnetic, and cytotoxic analyses to assess their suitability for MH applications. Through X-ray diffraction and Raman spectroscopy, it was possible to confirm the presence of the pure phase of CoFe2O4 in the sample treated at 1100 °C, exhibiting a saturation magnetization of 84 emu/g at 300 K and an average grain size of 542 nm. Furthermore, the sample treated at 1100 °C showed a specific absorption rate (SAR) of 3.91 W/g, and at concentrations equal to or below 5 mg/mL, is non-cytotoxic, being the most suitable for biomedical applications.

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Niobium oxide prepared by sol–gel using powder coconut water

Cited by 8 publications

References 41 publications

Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine

Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine

Potassium Ferrite for Biomedical Applications

Cobalt Ferrite Synthesized Using a Biogenic Sol–Gel Method for Biomedical Applications

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