scholarly journals Fractal aggregation and disaggregation of newly formed iron(iii) (hydr)oxide nanoparticles in the presence of natural organic matter and arsenic

2016 ◽  
Vol 3 (3) ◽  
pp. 647-656 ◽  
Author(s):  
Chelsea W. Neil ◽  
Jessica R. Ray ◽  
Byeongdu Lee ◽  
Young-Shin Jun
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Oxide Nanoparticles ◽  
Aggregation And Disaggregation ◽  
First Time

This study provides for the first timein situobservations of organic matter and arsenic effects on iron(iii) (hydr)oxide precipitation.

scholarly journals Stability of Fe-oxide nanoparticles coated with natural organic matter under relevant environmental conditions

2014 ◽  
Vol 70 (12) ◽  
pp. 2040-2046 ◽  
Author(s):  
L. Chekli ◽  
S. Phuntsho ◽  
L. D. Tijing ◽  
J. L. Zhou ◽  
J.-H. Kim ◽  
...  
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Environmental Conditions ◽  
Divalent Cations ◽  
Oxide Nanoparticles ◽  
Fe Oxide ◽  
Coated Nanoparticles ◽  
Aggregation Behaviour ◽  
Physico Chemical ◽  
The Stability

Manufactured nanoparticles (MNPs) are increasingly released into the environment and thus research on their fate and behaviour in complex environmental samples is urgently needed. The fate of MNPs in the aquatic environment will mainly depend on the physico-chemical characteristics of the medium. The presence and concentration of natural organic matter (NOM) will play a significant role on the stability of MNPs by either decreasing or exacerbating the aggregation phenomenon. In this study, we firstly investigated the effect of NOM concentration on the aggregation behaviour of manufactured Fe-oxide nanoparticles. Then, the stability of the coated nanoparticles was assessed under relevant environmental conditions. Flow field-flow fractionation, an emerging method which is gaining popularity in the field of nanotechnology, has been employed and results have been compared to another size-measurement technique to provide increased confidence in the outcomes. Results showed enhanced stability when the nanoparticles are coated with NOM, which was due to electrosteric stabilisation. However, the presence of divalent cations, even at low concentration (i.e. less than 1 mM) was found to induce aggregation of NOM-coated nanoparticles via bridging mechanisms between NOM and Ca2+.

AGGREGATION AND SURFACE PROPERTIES OF IRON OXIDE NANOPARTICLES: INFLUENCE OF pH AND NATURAL ORGANIC MATTER

2008 ◽  
Vol 27 (9) ◽  
pp. 1875 ◽  
Author(s):  
Mohammed Baalousha ◽  
Adriana Manciulea ◽  
Susan Cumberland ◽  
Kevin Kendall ◽  
Jamie R. Lead
Keyword(s):  
Organic Matter ◽  
Iron Oxide ◽  
Surface Properties ◽  
Iron Oxide Nanoparticles ◽  
Natural Organic Matter ◽  
Oxide Nanoparticles ◽  
Influence Of Ph

scholarly journals Discovery of functional gene markers of bacteria for monitoring hydrocarbon pollution in the marine environment - a metatranscriptomics approach

2019 ◽  
Author(s):  
Kamila Knapik ◽  
Andrea Bagi ◽  
Adriana Krolicka ◽  
Thierry Baussant
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Anthropogenic Pollution ◽  
Seasonal Effect ◽  
Marker Genes ◽  
Functional Markers ◽  
Gene Markers ◽  
Kegg Pathways ◽  
Oil Biodegradation

AbstractThe use of natural marine bacteria as “oil sensors” for the detection of pollution events can be suggested as a novel way of monitoring oil occurrence at sea. Nucleic acid-based devices generically called genosensors are emerging as potentially promising tools for in situ detection of specific microbial marker genes suited for that purpose. Functional marker genes are particularly interesting as targets for oil-related genosensing but their identification remains a challenge. Here, seawater samples, collected in tanks with oil addition mimicking a realistic oil spill scenario, were filtered and archived by the Environmental Sample Processor (ESP), a fully robotized genosensor, and the samples were then used for post-retrieval metatranscriptomic analysis. After extraction, RNA from ESP-archived samples at start, day 4 and day 7 of the experiment was used for sequencing. Metatranscriptomics revealed that several KEGG pathways were significantly enriched in samples exposed to oil. However, these pathways were highly expressed also in the non-oil-exposed water samples, most likely as a result of the release of natural organic matter from decaying phytoplankton. Temporary peaks of aliphatic alcohol and aldehyde dehydrogenases and monoaromatic ring-degrading enzymes (e.g. ben, box, and dmp clusters) were observed on day 4 in both control and oil tanks. Few alkane 1-monooxygenase genes were upregulated on oil, mostly transcribed by families Porticoccaceae and Rhodobacteraceae, together with aromatic ring-hydroxylating dioxygenases, mostly transcribed by Rhodobacteraceae. Few transcripts from obligate hydrocarbonoclastic genera of Alcanivorax, Oleispira and Cycloclasticus, were significantly enriched in the oil-treated tank in comparison to control, and these were mostly transporters and genes involved in nitrogen and phosphorous acquisition. This study highlights the importance of seasonality, i.e., phytoplankton occurrence and senescence leading to organic compound release which can be used preferentially by bacteria over oil compounds, delaying the latter process. As a result, such seasonal effect can reduce the sensitivity of genosensing tools employing bacterial functional genes to sense oil. A better understanding of the use of natural organic matter by bacteria involved in oil-biodegradation is needed to develop an array of functional markers enabling the rapid and specific in situ detection of anthropogenic pollution.

Facet-Dependent Adsorption and Fractionation of Natural Organic Matter on Crystalline Metal Oxide Nanoparticles

2020 ◽  
Vol 54 (14) ◽  
pp. 8622-8631 ◽  
Author(s):  
Zelin Shen ◽  
Zhanhua Zhang ◽  
Tong Li ◽  
Qingqian Yao ◽  
Tong Zhang ◽  
...  
Keyword(s):  
Organic Matter ◽  
Metal Oxide ◽  
Natural Organic Matter ◽  
Metal Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Crystalline Metal

scholarly journals Metatranscriptomic Analysis of Oil-Exposed Seawater Bacterial Communities Archived by an Environmental Sample Processor (ESP)

2020 ◽  
Vol 8 (5) ◽  
pp. 744
Author(s):  
Kamila Knapik ◽  
Andrea Bagi ◽  
Adriana Krolicka ◽  
Thierry Baussant
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Environmental Sample ◽  
Anthropogenic Pollution ◽  
Seasonal Effect ◽  
Marker Genes ◽  
Functional Markers ◽  
Kegg Pathways ◽  
In Situ Detection

The use of natural marine bacteria as “oil sensors” for the detection of pollution events can be suggested as a novel way of monitoring oil occurrence at sea. Nucleic acid-based devices generically called genosensors are emerging as potentially promising tools for in situ detection of specific microbial marker genes suited for that purpose. Functional marker genes are particularly interesting as targets for oil-related genosensing but their identification remains a challenge. Here, seawater samples, collected in tanks with oil addition mimicking a realistic oil spill scenario, were filtered and archived by the Environmental Sample Processor (ESP), a fully robotized genosensor, and the samples were then used for post-retrieval metatranscriptomic analysis. After extraction, RNA from ESP-archived samples at start, Day 4 and Day 7 of the experiment was used for sequencing. Metatranscriptomics revealed that several KEGG pathways were significantly enriched in samples exposed to oil. However, these pathways were highly expressed also in the non-oil-exposed water samples, most likely as a result of the release of natural organic matter from decaying phytoplankton. Temporary peaks of aliphatic alcohol and aldehyde dehydrogenases and monoaromatic ring-degrading enzymes (e.g., ben, box, and dmp clusters) were observed on Day 4 in both control and oil-exposed and non-exposed tanks. Few alkane 1-monooxygenase genes were upregulated on oil, mostly transcribed by families Porticoccaceae and Rhodobacteraceae, together with aromatic ring-hydroxylating dioxygenases, mostly transcribed by Rhodobacteraceae. Few transcripts from obligate hydrocarbonoclastic genera of Alcanivorax, Oleispira and Cycloclasticus were significantly enriched in the oil-treated exposed tank in comparison to control the non-exposed tank, and these were mostly transporters and genes involved in nitrogen and phosphorous acquisition. This study highlights the importance of seasonality, i.e., phytoplankton occurrence and senescence leading to organic compound release which can be used preferentially by bacteria over oil compounds, delaying the latter process. As a result, such seasonal effect can reduce the sensitivity of genosensing tools employing bacterial functional genes to sense oil. A better understanding of the use of natural organic matter by bacteria involved in oil-biodegradation is needed to develop an array of functional markers enabling the rapid and specific in situ detection of anthropogenic pollution.

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