“Sweet Chemistry”: a Green Way for Obtaining Selenium Nanoparticles Active against Cancer Cells

Abstract

We present an environment friendly synthesis of selenium nanoparticles and the study of their cytotoxic activity against uterine sarcoma cancer and fibroblasts cells. Amorphous selenium (a-SeNPs) and trigonal selenium (t-SeNPs) were synthesized using D-fructose as the reducing agent and characterized by high-resolution transmission electron microscopy (HRTEM), energydispersive X-ray spectroscopy (EDX), powder X-ray diffraction analysis (XRD), inductively coupled plasma optical emission spectrometry (ICP OES), dynamic light scattering (DLS) to obtain zeta potential values and cyclic voltammetry (CV). Particularly, a-SeNPs presented high toxicity toward the resistant cancer cell line MES-SA/Dx5 and its parental MES-SA line. However, they are not toxic against P4 fibroblast cells in comparative studies. Keywords: selenium nanoparticles, D-fructose, cancer cells, green chemistry, cytotoxicity IntroductionSelenium is an essential element of significant importance not only for humans, but also for other forms of life. 1,2 Inorganic seleno-compounds have strong antioxidant activity, as well as some pro-oxidant effects and, additionally, have great importance in nutrition and medicine. 3,4 Epidemiological studies have already demonstrated the potential role of selenium in the prevention and treatment of cancer cells. [5][6][7] For example, selenium supplementation showed effective reduction in the incidence of cancer in the cervix, lung and liver. 8 However, the biological activity of elemental selenium stands opposite to the selenium salts, since selenite and selenate showed inadequate cytotoxicity to normal cells. [9][10][11] In this sense, nanoparticles of elemental selenium stand out as an alternative, due to its low toxicity and acceptable bioavailability. [12][13][14] Nanoparticles have become increasingly prominent in the medical field in the last few decades, giving rise to a new area, nanomedicine. This new area is focused on developing nanomaterials with potential use in therapy and diagnosis of diseases, [15][16][17] including selenium nanoparticles (SeNPs). 18Generally, the methods for obtaining SeNPs involve multiple steps, high temperatures and pressures; require expensive equipment and reagents, as well as being harmful to the environment. [19][20][21][22][23][24][25][26][27] In this sense, it is necessary to develop simple routes that focus on green chemistry and no harm to the environment. Research has demonstrated the use of microorganisms such as bacteria, to reduce selenite. This method is considered a clean synthesis, but the cost and time of preparation of microbiological cultures is a disadvantage. 28-30The use of plant extracts and biopolymers such as chitosan, konjac glucomannan, gum acacia, carboxymethyl cellulose, sodium alginate and glutathione, as reducing agents of selenite has also been an alternative, since they are highly biodegradable and non-toxic materials. However, in each of these works there are several processing steps "Sweet Chemistry": a Green Way for Obtaining Selenium Nanop...

Microwave-Assisted Green Synthesis and Antioxidant Activity of Selenium Nanoparticles Using Theobroma cacao L. Bean Shell Extract

“…However, some peaks at higher diffraction angles 2θ (degrees) of 28.4, 31.6, 40.5, 45.5, 50.3, 56.6 and 66.6°, corresponding to different crystalline planes of SeNPs, were observed. These results are in agreement with those reported by Vieira et al who ascribed peaks at similar angles to the 100, 101, 102, 111, 201, 112 and 103 crystalline planes [17]. This pattern could be indexed according to the trigonal phase of SeNPs (crystalline t-SeNPs), in agreement with results obtained by Raman spectroscopy.…”

“…However, SeNPs obtained in that way show some limitations, such as their poor stability, so the addition of stabilizing agents during synthesis becomes necessary. Recent studies have reported that the functionalization of SeNPs with natural polysaccharides may improve effectively final nanoparticle stability, giving to these polysaccharide-conjugated SeNPs the desired properties [1,16,17]. Different plant extracts containing bioactive compounds, which can be used in synthesizing and stabilizing SeNPs, have been studied as response surface methodology (RSM) successfully applied to develop empirical models for the prediction of the SeNPs synthesis conditions [18,19].…”

Coloration and Multi-Functionalization of Polypropylene Fabrics with Selenium Nanoparticles

“…As illustrated in Figure 2 , SeNPs in a colloidal solution or into the PP fabric surface were highly crystalline. Additionally, the diffraction peaks at 24.28°, 29.24°, 43.64° and 64.28° were corresponding to 100, 101, 102 and 210 crystal planes, respectively, based on the JCPDS 86-2246 international database [ 38 ]. Moreover, the peaks at 13,66, 16.56, 18.18, and 25.38 can be observed for PP fabric, corresponding to the planes of (110), (040), (130), and (060), respectively [ 39 ].…”

Multifunctional Dyeing of Wool Fabrics Using Selenium Nanoparticles

“…As shown in Figure 3 , the obtained Se-NPs for both prepared solutions and Se-dyed wool fabrics were highly crystalline, and all diffraction peaks were well indexed as 24.28°, 29.24° and 43.64°, corresponding to 100, 101 and 102 crystal planes, respectively, in accordance with the JCPDS 86-2246 international database. [ 56 ] The results obtained from the SEM, EDX and XRD analyses confirmed the sufficient deposition of Se-NPs on the wool fabric surface.…”