Name: an experimental protocol for studying mineral effects on organic hydrothermal transformations
Uploaded: 2018-08-08T15:00:00
Description: Watch this Scientific Journal Video about An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations at JoVE.com

We thank the H.O.G. group at Arizona State University for developing the initial methodology of these hydrothermal experiments, and in particular, we thank I. Gould, E. Shock, L. Williams, C. Glein, H. Hartnett, K. Fecteau, K. Robinson, and C. Bockisch, for their guidance and helpful assistance. Z. Yang and X. Fu were funded by startup funds from Oakland University to Z. Yang.

1. Prepare the Sample for Hydrothermal Experiment
<ol>
	<li>Choose the size of the quartz or silica glass tubes, e.g., 2 mm inner diameter (ID) x 6 mm outer diameter (OD) or 6 mm ID x 12 mm OD, and determine the amounts of organic compounds and minerals to use. In this work, the amounts of nitrobenzene and magnetite (Fe3O4) to load into the silica tube (e.g., 2 mm ID x 6 mm OD) are 3.0 &#181;L and 13.9 mg, respectively. 
	NOTE: The large diameter tubes allow easier loading o...

<ol>
	<li>Yang, Z., Gould, I. R., Williams, L. B., Hartnett, H. E., Shock, E. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+iron-containing+minerals+on+hydrothermal+reactions+of+ketones.">Effects of iron-containing minerals on hydrothermal reactions of ketones.</a> Geochimica et Cosmochimica Acta. 223, 107-126 (2018).</li><li>Seewald, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organic-inorganic+interactions+in+petroleum-producing+sedimentary+basins.">Organic-inorganic interactions in petroleum-producing sedimentary basins.</a> Nature. 426 (6964), 327-333 (2003).</li><li>Sogin, M. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbial+diversity+in+the+deep+sea+and+the+underexplored+"rare+biosphere".">Microbial diversity in the deep sea and the underexplored "rare biosphere".</a> Proceedings of the National Academy of Sciences. 103 (32), 12115 (2006).</li><li>McCollom, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laboratory+Simulations+of+Abiotic+Hydrocarbon+Formation+in+Earth's+Deep+Subsurface.">Laboratory Simulations of Abiotic Hydrocarbon Formation in Earth's Deep Subsurface.</a> Reviews in Mineralogy and Geochemistry. 75 (1), 467-494 (2013).</li><li>Foustoukos, D. I., Seyfried, W. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrocarbons+in+Hydrothermal+Vent+Fluids:+The+Role+of+Chromium-Bearing+Catalysts.">Hydrocarbons in Hydrothermal Vent Fluids: The Role of Chromium-Bearing Catalysts.</a> Science. 304 (5673), 1002 (2004).</li><li>Bell, J. L. S., Palmer, D. A., Pittman, E. D., Lewan, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=10.1007/978-3-642-78356-2_9.">10.1007/978-3-642-78356-2_9.</a> Organic Acids in Geological Processes. , 226-269 (1994).</li><li>Palmer, D. A., Drummond, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+decarboxylation+of+acetate.+Part+I.+The+kinetics+and+mechanism+of+reaction+in+aqueous+solution.">Thermal decarboxylation of acetate. Part I. The kinetics and mechanism of reaction in aqueous solution.</a> Geochimica et Cosmochimica Acta. 50 (5), 813-823 (1986).</li><li>Yang, Z., Gould, I. R., Williams, L. B., Hartnett, H. E., Shock, E. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+central+role+of+ketones+in+reversible+and+irreversible+hydrothermal+organic+functional+group+transformations.">The central role of ketones in reversible and irreversible hydrothermal organic functional group transformations.</a> Geochimica et Cosmochimica Acta. 98, 48-65 (2012).</li><li>McCollom, T. M., Ritter, G., Simoneit, B. R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipid+Synthesis+Under+Hydrothermal+Conditions+by+Fischer-+Tropsch-Type+Reactions.">Lipid Synthesis Under Hydrothermal Conditions by Fischer- Tropsch-Type Reactions.</a> Origins of life and evolution of the biosphere. 29 (2), 153-166 (1999).</li><li>Bell, J. L. S., Palmer, D. A., Barnes, H. L., Drummond, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+decomposition+of+acetate:+III.+Catalysis+by+mineral+surfaces.">Thermal decomposition of acetate: III. Catalysis by mineral surfaces.</a> Geochimica et Cosmochimica Acta. 58 (19), 4155-4177 (1994).</li><li>Yang, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrothermal+Photochemistry+as+a+Mechanistic+Tool+in+Organic+Geochemistry:+The+Chemistry+of+Dibenzyl+Ketone.">Hydrothermal Photochemistry as a Mechanistic Tool in Organic Geochemistry: The Chemistry of Dibenzyl Ketone.</a> The Journal of Organic Chemistry. 79 (17), 7861-7871 (2014).</li><li>Yang, Z., Hartnett, H. E., Shock, E. L., Gould, I. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organic+Oxidations+Using+Geomimicry.">Organic Oxidations Using Geomimicry.</a> The Journal of Organic Chemistry. 80 (24), 12159-12165 (2015).</li><li>Venturi, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mineral-assisted+production+of+benzene+under+hydrothermal+conditions:+Insights+from+experimental+studies+on+C6+cyclic+hydrocarbons.">Mineral-assisted production of benzene under hydrothermal conditions: Insights from experimental studies on C6 cyclic hydrocarbons.</a> Journal of Volcanology and Geothermal Research. 346, 21-27 (2017).</li><li>Lemke, K. H., Rosenbauer, R. J., Bird, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peptide+Synthesis+in+Early+Earth+Hydrothermal+Systems.">Peptide Synthesis in Early Earth Hydrothermal Systems.</a> Astrobiology. 9 (2), 141-146 (2009).</li><li>Byrappa, K., Yoshimura, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Handbook of Hydrothermal Technology. , (2001).</li><li>Johnson, J. W., Oelkers, E. H., Helgeson, H. 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In this study, we used nitrobenzene with mineral magnetite as an example to demonstrate how to evaluate mineral effects on hydrothermal organic reactions. Although the experiments are carried out in small silica glass tubes, highly reproducible results are observed in the magnetite experiments, i.e., 30.3 &#177; 1.4% in nitrobenzene conversion, which suggests the effectiveness and the reliability of this hydrothermal protocol. In the no-mineral experiments, the conversion of nitrobenzene is 5.2 &#177; 2.1%, whic...

Hydrothermal environments (i.e., aqueous media at elevated temperatures and pressures) are ubiquitous on Earth. The hydrothermal chemistry of organic compounds plays an essential role in a wide range of geochemical settings, such as organic sedimentary basins, petroleum reservoirs, and the deep biosphere1,2,3. Organic carbon transformations in hydrothermal systems occur not only in pure aqueous medium but also with dissolved or solid inorganic materials, such as Earth-abundant minerals. Minerals have been found to dramatically and selectively influence the hydrothermal reactivity of various organic compounds,1,4,5 but how to identify the mineral effects in complex hydrothermal systems still remains as a challenge. The goal of this study is to provide a relatively simple experimental protocol for studying mineral effects on hydrothermal organic reactions.
The laboratory studies of hydrothermal reactions traditionally use robust reactors that are made of gold, titanium, or stainless steel6,7,8,9. For example, gold bags or capsules have been favorably used, because gold is flexible, and it allows the sample pressure to be controlled by pressurizing water externally, which avoids generating a vapor phase inside the sample. However, these reactors are expensive and could be associated with potential metal catalytic effects10. Hence, it is imperative to find an alternative method with low cost but high reliability for these hydrothermal experiments.
In recent years, reaction tubes made of quartz or fused silica glass have been more frequently applied to hydrothermal experiments11,12,13. Compared to precious gold or titanium, quartz or silica glass is considerably cheaper but also the strong material. More importantly, quartz tubes have shown little catalytic effects and can be as inert as gold for the hydrothermal reactions11,14. In this protocol, we describe a general method for conducting small-scale hydrothermal organic-mineral experiments in thick-walled silica tubes. We present an example experiment using a model compound (i.e., nitrobenzene) in the presence/absence of an iron-oxide mineral (i.e., magnetite) in a 150 &#176;C hydrothermal solution, in order to show the mineral effect, as well as to demonstrate the effectiveness of this method.

<table>
	<tbody>
		<tr>
			<td>Chemicals:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Dichloromethane</td>
			<td>VWR</td>
			<td>BDH23373.400</td>
			<td></td>
		</tr>
		<tr>
			<td>Dodecane</td>
			<td>Sigma-Aldrich</td>
			<td>297879</td>
			<td></td>
		</tr>
		<tr>
			<td>Nitrobenzene</td>
			<td>Sigma-Aldrich</td>
			<td>252379</td>
			<td></td>
		</tr>
		<tr>
			<td>Fe2O3</td>
			<td>Sigma-Aldrich</td>
			<td>310050</td>
			<td></td>
		</tr>
		<tr>
			<td>Fe3O4</td>
			<td>Sigma-Aldrich</td>
			<td>637106</td>
			<td></td>
		</tr>
		<tr>
			<td>Supplies:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Silica tube</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum pump</td>
			<td>WELCH</td>
			<td>2546B-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum line</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Oven</td>
			<td>Hewlett Packard</td>
			<td>5890</td>
			<td></td>
		</tr>
		<tr>
			<td>Thermocouple</td>
			<td>BENETECH</td>
			<td>GM1312</td>
			<td></td>
		</tr>
		<tr>
			<td>Gas chromatography</td>
			<td>Agilent</td>
			<td>7820A</td>
			<td></td>
		</tr>
	</tbody>
</table>

an experimental protocol for studying mineral effects on organic hydrothermal transformations

Organic-mineral interactions are widely occurring in hydrothermal environments, such as hot springs, geysers on land, and the hydrothermal vents in the deep ocean. Roles of minerals are critical in many hydrothermal organic geochemical processes. Traditional hydrothermal methodology, which includes using reactors made of gold, titanium, platinum, or stainless-steel, is usually associated with the high cost or undesired metal catalytic effects. Recently, there is a growing tendency for using the cost-effective and inert quartz or fused silica glass tubes in hydrothermal experiments. Here, we provide a protocol for carrying out organic-mineral hydrothermal experiments in silica tubes, and we describe the essential steps in the sample preparation, experimental setup, products separation, and quantitative analysis. We also demonstrate an experiment using a model organic compound, nitrobenzene, to show the effect of an iron-containing mineral, magnetite, on its degradation under a specific hydrothermal condition. This technique can be applied to study complex organic-mineral hydrothermal interactions in a relatively simple laboratory system.

To demonstrate how to use this approach to study hydrothermal organic-mineral interactions, a simple experiment using a model compound, nitrobenzene, was conducted with mineral magnetite (Fe3O4) at a hydrothermal condition of 150 &#176;C and 5 bars for 2 h. To show the mineral effect, an experiment of nitrobenzene without mineral was also performed under the same hydrothermal condition. As shown in Figure 1a, two silica tubes were made f...

Watch this Scientific Journal Video about An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations at JoVE.com

An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations

Earth-abundant minerals play important roles in the natural hydrothermal systems. Here, we describe a reliable and cost-effective method for the experimental investigation of organic-mineral interactions under hydrothermal conditions.

Organic-mineral interactions are widely occurring in hydrothermal environments, such as hot springs, geysers on land, and the hydrothermal vents in the ...

This method can help answer key questions in the organic chemistry field such as how earth abundant minerals influence organic molecules in deep ocean hydrothermal systems. The main advantage of this technique is that it is low cost, easy to use, and reliable. Though this method can provide insight into organic mineral interactions in natural hydrothermal systems, it can also be applied to other areas such as hydrothermal treatment of organic glutens or biofused hydrothermal synthesis in green chemistry.Demonstrating the procedure will be Dr.Xuan Fu from my lab. To begin this procedure, choose a tube size and material and determine the amounts of organic compounds and minerals to use, as outlined in the text protocol. This demonstration will be carried out using nitrobenzene and magnetite loaded into a silicon tube with an inner diameter of two millimeters and an outer diameter of six millimeters.Using a tube cutter, cut the tubing into small pieces about 30 centimeters in length. Then, use an oxyhydrogen torch with an appropriate flame head to seal one end of the tube closed. If any of the starting organic compounds are liquid, use a microliter syringe to transfer it into the tube.Using a pasteur pipette, add the pre-weighed materials. Then, add deionized and deoxygenated water. Connect the tube to a vacuum line with a closed valve.Use a clamp to tightly hold the tube and immerse it in a dewar flask filled with liquid nitrogen. Leave the tube in the liquid nitrogen for approximately three minutes until the organics and water are completely frozen. While the tube is still immersed in liquid nitrogen, open the vacuum valve to remove the air from the headspace of the tube.After this, switch off the valve. Remove the tube from the liquid nitrogen and let the tube warm up to room temperature. When it has warmed, gently tap the bottom of the tube to release any remaining air bubbles from the solution into the head space.Repeat this freeze, pump, thaw cycle twice more. Then, while the tube is still immersed in liquid nitrogen, close the vacuum line and use the oxyhydrogen torch to seal the open end of the tube. After the tube has been sealed, transfer it into a small steel pipe equipped with screw caps.Seal the screw caps loosely to prevent any damage from pressure build up or tube failure. Place the pipe inside a temperature controlled furnace or oven and heat it to the desired temperature. Use a thermocouple inside the oven to monitor the temperature throughout the hydrothermal reaction.As soon as the reaction time is reached, remove the pipe from the oven and put the tube into a cold water bath to quench the experiment. First, make dichloromethane extraction solution that contains 8.8 micromolar dodecane, as an internal standard for gas chromatography. Transfer three milliliters of the extraction solution into a 10 milliliter glass vial.Then, use a tube cutter to open the tube and use a pasteur pipette to quickly transfer all of the product into the glass vial. Next, vortex the solution for one minute. Let the mineral particles settle for five minutes.After this, use a pasteur pipette to carefully transfer approximately one milliliter of the sample from the dichloromethane layer into a GC vial. Using a polycapillary column and a flame ionization detector, analyze the product distribution by gas chromatography as outlined in the text protocol. Build the GC calibration curves and use them to quantify the organic products.Then, calculate the reaction conversion as outlines in the text protocol. Use these conversions to determine if the mineral facilitates or slows down the hydrothermal organic transformations. This approach to study hydrothermal organic mineral interactions is demonstrated here using nitrobenzene with the mineral magnetite at a hydrothermal condition of 150 degrees Celsius and five bars for two hours.After the hydrothermal process, the tube containing no magnetite showed no color change, while the tube that did contain magnetite turned a brown color. This implies that an oxidation reaction took place, with magnetite being converted into hematite. Gas chromatography analysis is then performed to determine the amount of magnetite on nitrobenzene conversion.In the no mineral experiment, the calculated conversion for nitrobenzene is seen to be 5.2%However, in the presence of magnetite, the nitrobenzene conversion is 30.3%an increase by a factor of six. This suggests that magnetite can significantly promote the reaction of nitrobenzene at the utilized hydrothermal conditions. While attempting this procedure, it's important to remember to follow the SOP of using the oxyhydrogen torch.So following this procedure, other analytical methods like scan electron microscopy and gas chromatography mass spectroscopy can be performed in order to answer additional questions, like whether there's morphology change of the minerals and what are the molecules masses of unknown organic products. After its development, this technique paved the way for researchers in the field of hydrothermal organic chemistry to explore organic mineral interactions in natural hydrothermal systems.

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Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of ...

Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid

Cervid phenotype can be placed into one of two categories: efficiency, which promotes survival over extravagant morphometric growth, and luxury, which promotes growth of large weaponry and body size. Populations of the same species display each phenotype depending on environmental conditions. Although antler and body size of male white-tailed deer (Odocoileus virginianus) varies by physiographic region in Mississippi, USA and is strongly correlated with regional variation in nutritional quality, the effects of population-level genetics from native stocks and previous re-stocking efforts cannot be disregarded. This protocol describes how we designed a controlled study, where other factors that influence phenotype, such as age and nutrition, are controlled. We brought wild-caught pregnant females and six-month-old fawns from three distinct physiographic regions in Mississippi, USA to the Mississippi State University Rusty Dawkins Memorial Deer Unit. Deer from the same region were bred to produce a second generation of offspring, allowing us to assess generational responses and maternal effects. All deer ate the same high-quality (20% crude protein deer pellet) diet ad libitum. We uniquely marked each neonate and recorded body mass, hind foot, and total body length. Each subsequent fall, we sedated individuals via remote injection and sampled the same morphometrics plus antlers of adults. We found that all morphometrics increased in size from first to second generation, with full compensation of antler size (regional variation no longer present) and partial compensation of body mass (some evidence of regional variation) evident in the second generation. Second generation males that originated from our poorest quality soil region displayed about a 40% increase in antler size and about a 25% increase in body mass when compared to their wild harvested counterparts. Our results suggest phenotypic variation of wild male white-tailed deer in Mississippi are more related to differences in nutritional quality than population-level genetics.

Phenotypic differences among cervid populations may be related to population-level genetics or nutrition; discerning which is difficult in the wild. This protocol describes how we designed a controlled study where nutritional variation was eliminated. We found that phenotypic variation of male white-tailed deer was more limited by nutrition than genetics.

Cervid phenotype can be placed into one of two categories: efficiency, which promotes survival over extravagant morphometric growth, and luxury, which ...

Experimental Column Setup for Studying Anaerobic Biogeochemical Interactions Between Iron (Oxy)Hydroxides, Trace Elements, and Bacteria

Fate and speciation of trace elements (TEs), such as arsenic (As) and mercury (Hg), in aquifers are closely related to physio-chemical conditions, such as redox potential (Eh) and pH, but also to microbial activities that can play a direct or indirect role on speciation and/or mobility. Indeed, some bacteria can directly oxidize As(III) to As(V) or reduce As(V) to As(III). Likewise, bacteria are strongly involved in Hg cycling, either through its methylation, forming the neurotoxin monomethyl mercury, or through its reduction to elemental Hg&#176;. The fates of both As and Hg are also strongly linked to soil or aquifer composition; indeed, As and Hg can bind to organic compounds or (oxy)hydroxides, which will influence their mobility. In turn, bacterial activities such as iron (oxy)hydroxide reduction or organic matter mineralization can indirectly influence As and Hg sequestration. The presence of sulfate/sulfide can also strongly impact these particular elements through the formation of complexes such as thio-arsenates with As or metacinnabar with Hg.
Consequently, many important questions have been raised on the fate and speciation of As and Hg in the environment and how to limit their toxicity. However, due to their reactivity towards aquifer components, it is difficult to clearly dissociate the biogeochemical processes that occur and their different impacts on the fate of these TE.
To do so, we developed an original, experimental, column setup that mimics an aquifer with As- or Hg-iron-oxide rich areas versus iron depleted areas, enabling a better understanding of TE biogeochemistry in anoxic conditions. The following protocol gives step by step instructions for the column set-up either for As or Hg, as well as an example with As under iron and sulfate reducing conditions.

Experimental Column Setup for Studying Anaerobic Biogeochemical Interactions Between Iron OxyHydroxides, Trace Elements, and Bacteria

Fate and speciation of arsenic and mercury in aquifers are closely related to physio-chemical conditions and microbial activity. Here, we present an original experimental column setup that mimics an aquifer and enables a better understanding of trace element biogeochemistry in anoxic conditions. Two examples are presented, combining geochemical and microbiological approaches.

Fate and speciation of trace elements (TEs), such as arsenic (As) and mercury (Hg), in aquifers are closely related to physio-chemical conditions, such as ...

Collection and Extraction of Occupational Air Samples for Analysis of Fungal DNA

Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several limitations that have resulted in the exclusion of many species. Advances in the field over the last two decades have led occupational health researchers to turn to molecular-based approaches for identifying fungal hazards. These methods have resulted in the detection of many species within indoor and occupational environments that have not been detected using traditional methods. This protocol details an approach for determining fungal diversity within air samples through genomic DNA extraction, amplification, sequencing, and taxonomic identification of fungal internal transcribed spacer (ITS) regions. ITS sequencing results in the detection of many fungal species that are either not detected or difficult to identify to species level using culture or microscopy. While these methods do not provide quantitative measures of fungal burden, they offer a new approach to hazard identification and can be used to determine overall species richness and diversity within an occupational environment.

Determining the fungal diversity within an environment is a method utilized in occupational health studies to identify health hazards. This protocol describes DNA extraction from occupational air samples for amplification and sequencing of fungal ITS regions. This approach detects many fungal species that can be overlooked by traditional assessment methods.

Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several ...

Experimental Protocol for Detecting Mitochondrial Function in Hepatocytes Exposed to Organochlorine Pesticides

This paper presents detailed methods on detecting hepatic mitochondrial function for a better understanding the cause of metabolic disorders caused by environmental organochlorine pesticides (OCPs) in hepatocytes. HepG2 cells were exposed to &#946;-hexachlorocyclohexane (&#946;-HCH) for 24 h at an equivalent dose of internal exposure in general population. Ultrastructure in hepatocytes was examined by transmission electron microscopy (TEM) to show the damage of mitochondria. Mitochondrial function was further evaluated by mitochondrial fluorescence intensity, adenosine 5'-triphosphate (ATP) levels, oxygen consumption rate (OCR) and mitochondrial membrane potential (MMP) in HepG2 cells incubated with &#946;-HCH. The mitochondria fluorescence intensity after stained by mitochondrial green fluorescent probe was observed with a fluorescence microscopy. The luciferin-luciferase reaction was used to determine ATP levels. The MMP was detected by the cationic dye JC-1 and analyzed under flow cytometry. OCR was measured with an extracellular flux analyzer. In summary, these protocols were used in detecting mitochondrial function in hepatocytes with to investigate mitochondria damages.

Understanding the influence of environmental organochlorine pesticides (OCPs) on mitochondrial function in hepatocytes is important in exploring the mechanism of OCPs causing metabolic disorders. This paper presents detailed methods on detecting hepatic mitochondrial function.

This paper presents detailed methods on detecting hepatic mitochondrial function for a better understanding the cause of metabolic disorders caused by ...