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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records

Metabolic response of environmentally isolated microorganisms to industrial effluents: Use of a newly described cell culture assay

An environmental application using a microtiter culture assay to measure the metabolic sensitivity of microorganisms to petrochemical effluents will be tested. The Biomedical Operations and Research Branch at NASA JSC has recently developed a rapid and nondestructive method to measure cell growth and metabolism. Using a colorimetric procedure the uniquely modified assay allows the metabolic kinetics of prokaryotic and eukaryotic cells to be measured. Use of such an assay if adapted for the routine monitoring of waste products, process effluents, and environmentally hazardous substances may prove to be invaluable to the industrial community. The microtiter method as described will be tested using microorganisms isolated from the Galveston Bay aquatic habitat. The microbial isolates will be identified prior to testing using the automated systems available at JSC. Sodium dodecyl sulfate (SDS), cadmium, and lead will provide control toxic chemicals. The toxicity of industrial effluent from two industrial sites will be tested. An effort will be made to test the efficacy of this assay for measuring toxicity in a mixed culture community.

Ferebee, Robert N.↗

Experiences with Lab-on-a-chip Technology in Support of NASA Supported Research

Under the auspices of the Microgravity Sciences and Application Department at Marshall Space Flight Center, we have custom designed and fabricated a lab-on-a-chip (LOC) device, along with Caliper Technologies, for macromolecular crystal growth. The chip has been designed to deliver specified proportions of up-to five various constituents to one of two growth wells (on-chip) for crystal growth. To date, we have grown crystals of thaumatin, glucose isomerase and appoferitin on the chip. The LOC approach offered many advantages that rendered it highly suitable for space based hardware to perform crystal growth on the International Space Station. The same hardware that was utilized for the crystal growth investigations, has also been used by researchers at Glenn Research Center to investigate aspects of microfluidic phenomenon associated with two-phase flow. Additionally, our LOCAD (Lab-on-a-chip Application Development) team has lent its support to Johnson Space Center s Modular Assay for Solar System Exploration project. At present, the LOCAD team is working on the design and build of a unique lab-on-a-chip breadboard control unit whose function is not commercially available. The breadboard can be used as a test bed for the development of chip size labs for environmental monitoring, crew health monitoring assays, extended flight pharmacological preparations, and many more areas. This unique control unit will be configured for local use and/or remote operation, via the Internet, by other NASA centers. The lab-on-a-chip control unit is being developed with the primary goal of meeting Agency level strategic goals.

Monaco, Lisa↗

Parabolic Flight Evaluation of Bacterial Adhesion on Multiple Antimicrobial Surface Treatments

This report describes the development of a test method and the evaluation of the effectiveness of antimicrobial technologies in reduced gravity based on parabolic flight experiments. Microbial growth is a common occurrence on fully immersed wetted surfaces in spacecraft environmental control and life support systems despite the use of chemical and/or physical \disinfection. Many materials and surface treatments with antimicrobial properties are commercially available but none have been vetted for spaceflight applications. Herein a test method is explained that included ground and reduced gravity parabolic flight experiments with a standard microorganism recovered from spacecraft, Pseudomonas aeruginosa, added at a concentration of 1 x 10(exp 5) cells per milliliter (mL) onto challenge material coupon surfaces. Several experimental materials were observed to slightly reduce microbial attachment in reduced gravity flight experiments, but none were capable of eliminating all challenge bacteria. Lunar gravity had an increased antimicrobial effect in 28 out of 36 test coupons compared to microgravity when provided otherwise identical conditions for growth, suggesting trace .amounts of gravity may be required for maximum antimicrobial performance. Bacterial cells exposed to variable gravity had more than twice as ,much intracellular adenosine triphosphate (ATP) when compared to control cells exposed only to Earth gravity due to a short duration response to environmental stress. An ATP luminescence assay was the method most amenable to development of an in-flight microbial monitoring assay

Birmele, Michele↗

Analysis of Volatile Compounds from CO2 Removal Systems

One of the primary concerns when designing CO2 scrubber systems that will be integrated with a Sabatier reactor to produce water and methane is the amount of water released from the scrubber. Because the gas stream entering a Sabatier reactor must be compressed, water entering the reactor can condense and compromise the integrity of the system, thus rendering its valuable conversion capability useless. When the Johnson Space Center Environmental Chemistry Laboratory was tasked to develop an assay to quantify the water concentration in air samples from CO2 scrubbers, additional testing was also performed to see if any other compounds were being concentrated on the scrubbers. It was thought that the efficiency of the scrubber systems could be quantified by comparing the differences in samples from the ambient air on the International Space Station (ISS) to the exit gas of the scrubber. As this analysis was carried out, it became evident that the concentrations of certain volatile compounds were higher in the samples from the scrubbers than they were in nominal environmental samples. This meant these compounds were being retained and concentrated on the scrubber beds. Based on this finding, concerns were raised about their potential for these compounds to poison the Sabatier reactor. Further investigation was required to identify these compounds due to their high concentrations and unique matrix of the CO2 scrubber exhaust. This paper describes these events as well as the process that was developed to identify the volatile compounds that increased. An examination of how much the certain compounds can be concentrated by the scrubber systems is also included.

Volatiles↗

Analysis of Volatile Compounds From CO2 Removal Systems

One of the primary concerns when designing CO2 scrubber systems that will be integrated with a Sabatier reactor to produce water and methane is the amount of water released from the scrubber. Because the gas stream entering a Sabatier reactor must be compressed, water entering the reactor can condense and compromise the integrity of the system, thus rendering its valuable conversion capability useless. When the Johnson Space Center Environmental Chemistry Laboratory was tasked to develop an assay to quantify the water concentration in air samples from CO2 scrubbers, additional testing was also performed to see if any other compounds were being concentrated on the scrubbers. It was thought that the efficiency of the scrubber systems could be quantified by comparing the differences in samples from the ambient air on the International Space Station (ISS) to the exit gas of the scrubber. As this analysis was carried out, it became evident that the concentrations of certain volatile compounds were higher in the samples from the scrubbers than they were in nominal environmental samples. This meant these compounds were being retained and concentrated on the scrubber beds. Based on this finding, concerns were raised about their potential for these compounds to poison the Sabatier reactor. Further investigation was required to identify these compounds due to their high concentrations and unique matrix of the CO2 scrubber exhaust. This paper describes these events as well as the process that was developed to identify the volatile compounds that increased. An examination of how much the certain compounds can be concentrated by the scrubber systems is also included.

Volatiles↗

Rapid Monitoring of Bacteria and Fungi aboard the International Space Station (ISS)

Microorganisms within spacecraft have traditionally been monitored with culture-based techniques. These techniques involve growth of environmental samples (cabin water, air or surfaces) on agar-type media for several days, followed by visualization of resulting colonies or return of samples to Earth for ground-based analysis. Data obtained over the past 4 decades have enhanced our understanding of the microbial ecology within space stations. However, the approach has been limited by the following factors: i) Many microorganisms (estimated > 95%) in the environment cannot grow on conventional growth media; ii) Significant time lags (3-5 days for incubation and up to several months to return samples to ground); iii) Condensation in contact slides hinders colony counting by crew; and iv) Growth of potentially harmful microorganisms, which must then be disposed of safely. This report describes the operation of a new culture-independent technique onboard the ISS for rapid analysis (within minutes) of endotoxin and beta-1, 3-glucan, found in the cell walls of gramnegative bacteria and fungi, respectively. The technique involves analysis of environmental samples with the Limulus Amebocyte Lysate (LAL) assay in a handheld device, known as the Lab-On-a-Chip Application Development Portable Test System (LOCAD-PTS). LOCADPTS was launched to the ISS in December 2006, and here we present data obtained from Mach 2007 until the present day. These data include a comparative study between LOCADPTS analysis and existing culture-based methods; and an exploratory survey of surface endotoxin and beta-1, 3-glucan throughout the ISS. While a general correlation between LOCAD-PTS and traditional culture-based methods should not be expected, we will suggest new requirements for microbial monitoring based upon culture-independent parameters measured by LOCAD-PTS.

Gunter, D.↗

LOCAD-PTS: Operation of a New System for Microbial Monitoring Aboard the International Space Station (ISS)

Microorganisms within the space stations Salyut, Mir and the International Space Station (ISS), have traditionally been monitored with culture-based techniques. These techniques involve growing environmental samples (cabin water, air or surfaces) on agar-type media for several days, followed by visualization of resulting colonies; and return of samples to Earth for ground-based analysis. This approach has provided a wealth of useful data and enhanced our understanding of the microbial ecology within space stations. However, the approach is also limited by the following: i) More than 95% microorganisms in the environment cannot grow on conventional growth media; ii) Significant time lags occur between onboard sampling and colony visualization (3-5 days) and ground-based analysis (as long as several months); iii) Colonies are often difficult to visualize due to condensation within contact slide media plates; and iv) Techniques involve growth of potentially harmful microorganisms, which must then be disposed of safely. This report describes the operation of a new culture-independent technique onboard the ISS for rapid analysis (within minutes) of endotoxin and -1, 3-glucan, found in the cell walls of gram-negative bacteria and fungi, respectively. This technique involves analysis of environmental samples with the Limulus Amebocyte Lysate (LAL) assay in a handheld device. This handheld device and sampling system is known as the Lab-On-a-Chip Application Development Portable Test System (LOCAD-PTS). A poster will be presented that describes a comparative study between LOCAD-PTS analysis and existing culture-based methods onboard the ISS; together with an exploratory survey of surface endotoxin throughout the ISS. It is concluded that while a general correlation between LOCAD-PTS and traditional culture-based methods should not necessarily be expected, a combinatorial approach can be adopted where both sets of data are used together to generate a more complete story of the microbial ecology on the ISS.

Maule, J.↗

The NASA Open Science Data Repository: Biomedical Data, Analysis Tools, and Informatic Collaborations

Increased biomedical risks and challenges associated with deep space missions require knowledge discovery, health countermeasures, and biomedical support capabilities. Maximally open-access and reusable data is needed by developers, scientists, and engineers to develop these systems. The NASA Open Science Data Repository (OSDR) is a maximally open access and FAIR database (ie., findable, accessible, interoperable, and reusable), and meets various scientific, technical, and operational needs. It offers users and submitters the ability to upload, download, search, share, analyze, cite, and visualize data across ‘omics, physiological, phenotypic, payload, hardware, behavioral, bioimaging, video, and environmental monitoring telemetry datasets. OSDR is an expanded database, based upon the successes of NASA GeneLab. OSDR has >460 studies with datasets covering model organisms to non-NASA human astronauts. There are ~12 datasets from the Inspiration 4 (I4) mission, spanning metagenomics, comprehensive metabolic panels, clonal hematopoiesis, spatial transcriptomics, proteomics, and cytokine panels. In the interest of data privacy, two I4 datasets with raw files relating to the epitranscriptome, and a new request feature is live in OSDR (with a backend review process established) developed from industry norms. OSDR is collecting and curating biomedical human data from a new sub-orbital research flight and is open to more space life science/biomedical submissions from the international and commercial sectors. OSDR also recently began a collaboration with the European Space Agency (ESA) to collect and curate >200 terabytes of human and model organism data. The OSDR submission portal is designed to ingest and curate ~25 ‘omics and ~50 physiological-phenotypic-imaging assay data types. Tools available for OSDR users include: 1) an Environmental Data Application to compare radiation, CO2, relative humidity, temperature, and other telemetry across missions and subjects, 2) the RadLab database, a collaboration between NASA, ESA, the German and Italian Space Agencies, and the Bulgarian Academy of Sciences, and 3) a Multi-study visualization tool which enables users to look across and combine ‘omics datasets. There are ~600 volunteer OSDR Analysis Working Group (AWG) members providing feedback on scientific data/metadata standards and collaborating to mine-reuse OSDR in research. OSDR/GeneLab has enabled ~60 publications reusing data as of October 2023.

space biology↗

Response of terrestrial microorganisms to a simulated Martian environment

Soil samples from Cape Canaveral were subjected to a simulated Martian environment and assayed periodically over 45 days to determine the effect of various environmental parameters on bacterial populations. The simulated environment was based on the most recent available data, prior to the Viking spacecraft, describing Martian conditions and consisted of a pressure of 7 millibars, an atmosphere of 99.9% CO2 and 0.1% O2, a freeze-thaw cycle of -65 C for 16 h and 24 C for 8 h, and variable moisture and nutrients. Reduced pressure had a significant effect, reducing growth under these conditions. Slight variations in gaseous composition of the simulated atmosphere had negligible effect on growth. The freeze-thaw cycle did not inhibit growth, but did result in a slower rate of decline after growth had occurred. Dry samples exhibited no change during the 45-day experiment, indicating that the simulated Martian environment was not toxic to bacterial populations. Psychrotrophic organisms responded more favorably to this environment than mesophiles, although both types exhibited increases of approximately 3 logs in 7 to 14 days when moisture and nutrients were available.

Foster, T. L.↗

Biomass measurement of methane forming bacteria in environmental samples

Methane-forming bacteria contain unusual phytanylglycerol ether phospholipids which can be extracted from the bacteria in sediments and assayed quantitatively by high performance liquid chromatography (HPLC). In this procedure the lipids were extracted, the phospholipids recovered, hydrolyzed, purified by thin layer chromatography, derivatized and assayed by HPLC. Ether lipids were recovered quantitatively from Methanobacterium thermoautotrophicum and sediments at levels as low as 8 x 10(-14) moles. In freshwater and marine sediments the flux of methane to the atmosphere and the methane levels in the pore water reflects the recovery of the phytanyl glycerol ether lipid 'signature'. The proportion of the ether phospholipid to the total recoverable phospholipid was highest in anaerobic digester sewage sludge and deeper subsurface freshwater sediment horizons.

Methanobacterium/metabolism/physiology↗

Effects of substrates and phosphate on INT (2-(4-iodophenyl)-3-(4-nitrophenyl)-5-phenyl tetrazolium chloride) and CTC (5-cyano-2,3-ditolyl tetrazolium chloride) reduction in Escherichia coli

The effects of substrates of primary aerobic dehydrogenases, and inorganic phosphate on aerobic INT and CTC reduction in Escherichia coli were examined. In general, INT produced less formazan than CTC, but INT (+) cell counts remained near values of CTC (+) cells. INT and CTC (+) cell numbers were higher than plate counts on R2A medium using succinate, formate, lactate, casamino acids, glucose, glycerol (INT only) and no substrate. Formate resulted in the greatest amount of INT and CTC formazan. Reduction of both INT and CTC was inhibited above 10 mmol l-1 phosphate, and this appeared to be related to decreased rates of O2 consumption. Formation of fluorescent CTC (+), but not INT (+) cells was also inhibited in a concentration dependent manner by phosphate above 10 mmol l-1. From light microscopic observations it appeared CTC formed increasing amounts of poorly or non-fluorescent formazan with increasing phosphate. Therefore, use of phosphate buffer in excess of 10 mmol l-1 may not be appropriate in CTC and INT reduction assays.

NASA Program Environmental Health↗

From Space to the Patient: A New Cytokine Release Assay to Monitor the Immune Status of HIV Infected Patients and Sepsis Patients

Monitoring of humans either in the healthy men under extreme environmental stress like space flight, in human immunodeficiency virus (HIV) infected patients or in sepsis is of critical importance with regard to the timing of adequate therapeutic (counter-)measures. The in vivo skin delayed-type hypersensitivity test (DTH) served for many years as a tool to evaluate cell mediated immunity. However, this standardised in vivo test was removed from the market in 2002 due to the risk of antigen stabilization. To the best of our knowledge an alternative test as monitoring tool to determine cell mediated immunity is not available so far. For this purpose we tested a new alternative assay using elements of the skin DTH which is based on an ex vivo cytokine release from whole blood and asked if it is suitable and applicable to monitor immune changes in HIV infected patients and in patients with septic shock.

Kaufmann, I.↗

A study of psychrophilic organisms isolated from the manufacture and assembly areas of spacecraft to be used in the Viking mission

The ability of psychrophilic microorganisms to grow in some of the environmental conditions suggested for Mars is studied with particular attention given to the effects of moisture and nutrients on growth. Results of growth with the slide culture technique are presented and indicate that this technique can be a rapid and sensitive technique for demonstration of microbial growth under various environmental conditions. Additional soil samples have been obtained from Cape Kennedy, and results of these assays at various low temperatures for psychrophilic populations are presented. The heat resistance of some of the psychrophilic sporeformers have been determined. Psychrophilic organisms were isolated from the teflon ribbons at Cape Kennedy and characterization of these was begun. In addition, heat survivors from the teflon ribbons are being investigated, and partial characterizations of these are presented.

Foster, T. L.↗

Oil Dispersant Corexit 9500 Is Weakly Estrogenic, but Does Not Skew the Sex Ratio in Alligator Mississippiensis

During the Deepwater Horizon oil spill, vast quantities of the chemical dispersant Corexit 9500 were applied in remediation efforts. In addition to the acute toxicity and obesogenicity of Corexit, it is important to further evaluate Corexit with long-term sublethal endocrine endpoints. The American alligator (Alligator mississippiensis) exhibits temperature-dependent sex determination, in which egg incubation temperatures during a thermosensitive period (TSP) in embryonic development determine sex of the embryos. Estrogen signals also play critical roles in this process. For example, a single exposure to exogenous estrogen during the TSP overrides the effects of temperature and leads to skewed sex ratios. At a dose of 100 ppm, Corexit significantly induced transcriptional activity of both alligator nuclear estrogen receptors 1 and 2 in vitro using the reporter gene assays. To investigate the estrogenic effects on gonadal development in ovo, alligator eggs were exposed to Corexit at environmentally relevant concentrations (0.25, 2.5, and 25 ppm) prior to the TSP. Significant delays in the hatching and growth were observed in 0.25 and 25 ppm Corexit exposed groups. At one week of age, no significant effects on sex ratios or testicular mRNA abundance were observed as a result of exposure to Corexit at the tested exposure levels, suggesting Corexit does not have strong estrogenic activity in ovo. Further investigations are required using individual components of Corexit to better understand their estrogenic effects on the development and reproductive health of alligators and other coastal aquatic wildlife.

Nicole Mcnabb↗

Cytometer on a chip

An assay technique for label-free, highly parallel, qualitative and quantitative detection of specific cell populations in a sample and for assessing cell functional status, cell-cell interactions and cellular responses to drugs, environmental toxins, bacteria, viruses and other factors that may affect cell function. The technique includes a) creating a first array of binding regions in a predetermined spatial pattern on a sensor surface capable of specifically binding the cells to be assayed; b) creating a second set of binding regions in specific spatial patterns relative to the first set designed to efficiently capture potential secreted or released products from cells captured on the first set of binding regions; c) contacting the sensor surface with the sample, and d) simultaneously monitoring the optical properties of all the binding regions of the sensor surface to determine the presence and concentration of specific cell populations in the sample and their functional status by detecting released or secreted bioproducts.

Lynes, Michael A.↗

The Archaeology of Little Wood Creek: New Chronometric Evidence

This study reports on the establishment of viable dates for several major cultural components at the Little Wood Creek site on the upper Hudson in Fort Edward, New York. The original excavation in the mid-1980s (Grossman et al. 1990) resulted in the identification of two major periods of occupation, a deeply buried Transitional period sequence of living floors, and closer to the surface, and separated by circa five feet of sterile alluvium, a series of Late Woodland period pits and features. Both are overlain by the discovery of the southern bastion of Revolutionary War-era Fort Edward. Ambiguities in the original bulk radiocarbon dating of the site left it in chronological limbo with widely divergent determinations for both prehistoric occupation periods. New AMS dates from 10 samples, four Transitional period and six Late Woodland period assays, both refined the absolute chronology of the site complex and clarified several major issues in the cultural and environmental history of the region. Together, these two sets of dates, combined with recent high resolution environmental sequences, provide sufficient resolution to correlate the newly defined periods of occupation with major events in the pollen and climate record of eastern New York State.

chronology↗

Antibody binding in altered gravity: implications for immunosorbent assay during space flight

A single antibody-incubation step of an indirect, enzyme-linked immunosorbent assay (ELISA) was performed during microgravity, Martian gravity (0.38 G) and hypergravity (1.8 G) phases of parabolic flight, onboard the NASA KC-135 aircraft. Antibody-antigen binding occurred within 15 seconds; the level of binding did not differ between microgravity, Martian gravity and 1 G (Earth's gravity) conditions. During hypergravity and 1 G, antibody binding was directly proportional to the fluid volume (per microtiter well) used for incubation; this pattern was not observed during microgravity. These effects in microgravity may be due to "fluid spread" within the chamber (observed during microgravity with digital photography), leading to greater fluid-surface contact and subsequently antibody-antigen contact. In summary, these results demonstrate that: i) ELISA antibody-incubation and washing steps can be successfully performed by human operators during microgravity, Martian gravity and hypergravity; ii) there is no significant difference in antibody binding between microgravity, Martian gravity and 1 G conditions; and iii) a smaller fluid volume/well (and therefore less antibody) was required for a given level of binding during microgravity. These conclusions indicate that reduced gravity would not present a barrier to successful operation of immunosorbent assays during spaceflight.

NASA Discipline Environmental Health↗

Automating Microbial Directed Evolution For Bioengineering Applications

From a micro-biology perspective, directed evolution is a technique that uses controlled environmental pressures to select for a desired phenotype. Directed evolution has the distinct advantage over rational design of not needing extensive knowledge of the genome or pathways associated with a microorganism to induce phenotypes. However, there are currently limitations to the applicability of this technique including being time-consuming, error-prone, and dependent on existing assays that may lack selectivity for the given phenotype. The AADEC (Autonomous Adaptive Directed Evolution Chamber) system is a proof-of-concept instrument to automate and improve the technique such that directed evolution can be used more effectively as a general bioengineering tool. A series of tests using the automated system and comparable by-hand survival assay measurements have been carried out using UV-C radiation and Escherichia coli cultures in order to demonstrate the advantages of the AADEC versus traditional implementations of directed evolution such as random mutagenesis. AADEC uses UV-C exposure as both a source of environmental stress and mutagenesis, so in order to evaluate the UV-C tolerance obtained from the cultures, a manual UV-C exposure survival assay was developed alongside the device to compare the survival fractions at a fixed dosage. This survival assay involves exposing E. coli to UV-C radiation using a custom-designed exposure hood to control the flux and dose. Surviving cells are counted then transferred to the next iteration and so on for several iterations to calculate the survival fractions for each exposure iteration.This survival assay primarily serves as a baseline for the AADEC device, allowing quantification of the differences between the AADEC system over the manual approach. The primary data of comparison is survival fractions; this is obtained by optical density and plate counts in the manual assay and by optical density growth curve fits pre- and post-exposure in the automated case. This data can then be compiled to calculate trends over the iterations to characterize increasing UV-C resistance of the E.coli strains. The observed trends are statistically indistinguishable through several iterations from both sources.

Bioengineering↗