Synthesis of Gold Nanoparticles by Blue-Green Algae Spirulina Platensis

The synthesis of gold nanoparticles by one of the many popular microorganisms – blue-green algae Spirulina platensis was studied. The complex of optical and analytical methods was applied for investigation of experimental samples after exposure to chloroaurate (HAuCl4) solution at different doses and for different time intervals. To characterize formed gold nanoparticles UV-vis Spectrometry, Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy-dispersive analysis of X-rays (EDAX) were used. It was shown that after 1.5 – 2 days of exposure the extracellular formation of nanoparticles of spherical form and the distribution peak within the interval of 20-30 nm took place. To determine gold concentrations in the Spirulina platensis biomass neutron activation analysis (NAA) was applied. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3496

MERCURY ADSORPTION BY ARTHOBACTER GLOBIFORMIS AND SPIRULINA PLATENSIS

Abstract. The increasing contamination of soil, sediment, and water with heavy metals by natural and industrial processes is a worldwide problem. Many bacteria and microalgae have demonstrated ability to absorb toxic elements. To study mercury biosorption by bacteria Arthrobacter globiformis and microalga Spirulina platensis neutron activation analysis (NAA) was applied. The process of mercury biosorption by these media was described by Freundlich and Langmuir-Freundlich Model. Both microorganisms showed a great potential to be used as biosorbing agents for mercury removal from the environment

Comparison of ICP-MS, ICP-OES, INAA, and WDXRF Techniques in Measuring Elements in Coniferous Needles Samples

The elemental composition of plant matrices has been conventionally determined by spectrometric techniques such as Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) [1]. Wet mineralization (digestion) of samples requires time, equipment, and usage of aggressive and toxic chemicals which are the main drawbacks of those routinely used techniques [2]. The need for suitable analytical methods for direct and multi-elemental analysis of plant samples has been increased in recent years [3]. Instrumental Neutron Activation Analysis (INAA) is one of the techniques for direct analysis which has been previously applied in environmental studies, nevertheless it is not a commonly used technique for plant samples. X-ray fluorescence (XRF) is another technique with the possibility of performing multi-element analysis directly on solid samples with numerous advantages. Although non-destructive techniques (INAA and XRF) are widely accepted in various fields of screening tests regarding the analytical approach, their performance needs to be evaluated in plant sample analysis. The main aim of this research was to assess how reliable non-destructive techniques are in detecting elements in conifer needles regarding routinely used spectrometric techniques. A total of 49 plant samples of four conifer species (Pinus nigra, Abies alba, Taxus baccata, and Larix decidua) were measured using two routinely used (ICPMS and ICP-OES) and two non-destructive instrumental techniques (WD-XRF and INAA). A quality control program included NIST pine needles certified reference material (1575a) analysis using all examined techniques. The techniques were compared by examination of relative ratio (element concentration measured using investigated analytical techniques divided by concentration determined by ICP-MS (figure 1)) and by correlation. Precision of all examined techniques was additionally investigated. This study confirmed that non-destructive spectroscopic techniques can be successfully applied on plant samples since sample preparation for these techniques is fast and in good accordance with the principles of green chemistry. Investigated standardless XRF method can also produce well-correlated results, compared to other techniques based on calibration standards. Obtained results suggest that the high accuracy of the analysis can be ensured by additional analytical and quality control steps (the use of internal standards, standard addition, etc.)

SYNTHESIS OF GOLD NANOPARTICLES BY BLUE-GREEN ALGAE Spirulina platensis

Kalabegishvili T. et al. E14-2012-31 Synthesis of Gold Nanoparticles by Blue-Green Algae Spirulina platensis The synthesis of gold nanoparticles by one of the many popular microorganisms Å blue-green algae Spirulina platensis was studied. The complex of optical and analytical methods was applied for investigation of experimental samples after exposure to chloroaurate (HAuCl4) solution at different doses and for different time intervals. To characterize formed gold nanoparticles UV-vis, TEM, SEM, EDAX, and XRD were used. It was shown that after 1.5Ä2 days of exposure the extracellular formation of nanoparticles of spherical form and the distribution peak within the interval of 20Ä30 nm took place. To determine gold concentrations in the Spirulina platensis biomass, neutron activation analysis (NAA) and atomic absorption spectrometry (AAS) were applied. The results obtained evidence that the concentration of gold accumulated by Spirulina biomass is rapidly growing in the beginning, followed by some increase for the next few days. The obtained substance of Spirulina biomass with gold nanoparticles may be used for medical, pharmaceutical, and technological purposes. The investigation has been performed a

Using moss Ceratodon purpureus (Hedw.) Brid for assessing the technogenic pollution (Ni, Zn, Mn, Al, Se, Cs, La, and Sm) of transformed ecotopes of Donbass

The ecotopic difference in the accumulation of Ni, Zn, Mn, Al, Se, Cs, La and Sm in bryophyte Ceratodon purpureus (Hedw.) Brid was studied during a long-term experiment in the anthropogenically disturbed environment of Donbass. The concentrations of elements in moss gametophytes were determined by neutron activation analysis. The moss samples were exposed from November 2018 through May 2019 at 24 test plots in the central Donbass with varying degrees of technogenic transformation of geosystems. When comparing ecologically stressed areas with intact or restored ecotopes, the difference in the accumulation of Ni was 6.9 times, Zn – 10.2, Mn – 6.3, Al – 5.3, Se – 9.6, Cs – 3.9, La – 5.9, and Sm – 5.4 times. There were structural and functional modifications in the leaf apparatus of bryophyte, suitable for using in further phytomonitoring studies for express diagnostics. According to the results of the factor analysis, two groups of pollutants were identified, differing in the source of origin: (1) Al, Ni, Mn, and Zn, (2) Cs, Se, La, and Sm. The obtained data are considered as part of the primary screening of biogeochemical characteristics in the Donbass in 2018–2019. Within the gradient of toxic load and local impact, the leading role of mining and metallurgical facilities in the pollution of natural ecosystems of Donbass was proved

MERCURY ADSORPTION BY ARTHOBACTER GLOBIFORMIS AND SPIRULINA PLATENSIS

The increasing contamination of soil, sediment, and water with heavy metals by natural and industrial processes is a worldwide problem. Many bacteria and microalgae have demonstrated ability to absorb toxic elements. To study mercury biosorption by bacteria Arthrobacter globiformis and microalga Spirulina platensis neutron activation analysis (NAA) was applied. The process of mercury biosorption by these media was described by Freundlich and Langmuir-Freundlich Model. Both microorganisms showed a great potential to be used as biosorbing agents for mercury removal from the environment

EPITHERMAL NEUTRON ACTIVATION ANALYSIS FOR BACTERIAL TRANSFORMATIONS OF CHROMIUM

Most powerful primary analytical technique, neutron activation analysis, was applied to study indigenous bacteria, namely, Arthrobacter genera which can be successfully used in detoxification and immobilization of toxic substances. In the present study the effect of Cr(VI) on the elemental content of these bacteria has been examined. The concentrations from 12 to 19 elements such as Na, Al, Cl, K, Fe, Co, Zn, As, Br, Rb, Sr, Sb, Ba, Tb, Th, U were determined in the bacterial cells. The high rate of Cr accumulation in the tested bacterial cells was shown. In bacteria treated with chromate some similarity in the behaviour of the following essential elements − potassium, sodium, chlorine − was observed. Such non-essential elements as Ag, As, Br and U were determined in all bacteria and have to be considered by cells as toxins