Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The design and construction of an oxygen micro-electrode for monitoring 20-100 microliter volumes.

ABSTRACT: Full instructions are given for the construction of a micro-respirometer. It is based on a membrane-covered platinum electrode of 10 micron diameter that consumes little oxygen. The reaction chamber, made entirely of glass, can be varied in volume between 20 and 100 microliter by adjusting the sealer assembly. Although specifically designed to study the properties of small samples of mitochondria from tiny organisms, it can be used equally well either for oxygen dissolved in aqueous solutions or dry gas mixtures containing oxygen. Measurements can be made with about one-hundredth the amount of material required for commercially available macro-respirometers, and when connected via an impedance-matching device to a pen recorder it gives a stable output of 100-200 mV in air.

SUBMITTER: Huskisson NS

PROVIDER: S-EPMC1144104 | biostudies-other | 1984 Aug

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Optoacoustic micro-tomography at 100 volumes per second.

Project description:Optical microscopy remains a fundamental tool for modern biological discovery owing to its excellent spatial resolution and versatile contrast in visualizing cellular and sub-cellular structures. Yet, the time domain is paramount for the observation of biological dynamics in living systems. Commonly, acquisition of microscopy data involves scanning of a spherically- or cylindrically-focused light beam across the imaged volume, which significantly limits temporal resolution in 3D. Additional complications arise from intense light scattering of biological tissues, further restraining the effective penetration depth and field of view of optical microscopy techniques. To overcome these limitations, we devised a fast optoacoustic micro-tomography (OMT) approach based on simultaneous acquisition of 3D image data with a high-density hemispherical ultrasound array having effective detection bandwidth beyond 25?MHz. We demonstrate fast three-dimensional imaging of freely-swimming zebrafish larvae, achieving 3D imaging speed of 100 volumes per second with isotropic spatial resolution approaching the dimensions of large cells across a field of view exceeding 50mm3. As opposed to other microscopy techniques based on optical contrast, OMT resolves optical absorption acoustically using unfocused light excitation. Thus, no penetration barriers are imposed by light scattering in deep tissues, suggesting it as a powerful approach for multi-scale functional and molecular imaging applications.

| S-EPMC5537301 | biostudies-literature

Capillary Blood GSH Level Monitoring, Using an Electrochemical Method Adapted for Micro Volumes.

Project description:Glutathione (?-glutamyl-cysteinyl-glycine; also known as GSH) is an endogenous antioxidant that plays a crucial role in cell defense mechanisms against oxidative stress. It is thus not surprising that this molecule can serve as a biomarker for oxidative stress monitoring. As capillary blood is a highly accessible target for biomarking, it is a valuable bodily fluid for diagnosing human GSH levels. This study focused on the optimization of GSH measurements from micro volumes of capillary blood prior to using electrochemical detection. The optimization of experimental parameters, including the sample volume and its stability, was performed and evaluated. Moreover, we tested the optimized method as part of a short-term study. The study consisted of examining 10 subjects within 96 h of their consumption of high amounts of antioxidants, attained from a daily dose of 2 g/150 mL of green tea. The subjects' capillary blood (5 ?L) was taken at 0 h, 48 h, and 96 h for subsequent analysis. The short-term supplementation of diet with green tea showed an increase of GSH pool by approximately 38% (between 0 and 48 h) within all subjects.

| S-EPMC6222753 | biostudies-literature

Electrochemical Evaluation of a Multi-Site Clinical Depth Recording Electrode for Monitoring Cerebral Tissue Oxygen.

Project description:The intracranial measurement of local cerebral tissue oxygen levels-PbtO2-has become a useful tool for the critical care unit to investigate severe trauma and ischemia injury in patients. Our preliminary work in animal models supports the hypothesis that multi-site depth electrode recording of PbtO2 may give surgeons and critical care providers needed information about brain viability and the capacity for better recovery. Here, we present a surface morphology characterization and an electrochemical evaluation of the analytical properties toward oxygen detection of an FDA-approved, commercially available, clinical grade depth recording electrode comprising 12 Pt recording contacts. We found that the surface of the recording sites is composed of a thin film of smooth Pt and that the electrochemical behavior evaluated by cyclic voltammetry in acidic and neutral electrolyte is typical of polycrystalline Pt surface. The smoothness of the Pt surface was further corroborated by determination of the electrochemical active surface, confirming a roughness factor of 0.9. At an optimal working potential of -0.6 V vs. Ag/AgCl, the sensor displayed suitable values of sensitivity and limit of detection for in vivo PbtO2 measurements. Based on the reported catalytical properties of Pt toward the electroreduction reaction of O2, we propose that these probes could be repurposed for multisite monitoring of PbtO2in vivo in the human brain.

| S-EPMC7407998 | biostudies-literature

A General Electrode Design Strategy for Flexible Fiber Micro-Pseudocapacitors Combining Ultrahigh Energy and Power Delivery.

Project description:Herein, a general strategy is proposed to boost the energy storage capability of pseudocapacitive materials (i.e., MnO2) to their theoretical limits in unconventional 1D fiber configuration by rationally designing bicontinuous porous Ni skeleton@metal wire "sheath-core" metallic scaffold as a versatile host. As a proof of concept, the 1D metallic scaffold supported-MnO2 fiber electrode is demonstrated. The proposed "sheath" design not only affords large electrode surface area with ordered macropores for large electrolyte-ion accessibility and high electroactive material loading, but also renders interconnected porous metallic skeleton for efficient electronic and ionic transport, while the metallic "core" functions as an extra current collector to promote long-distance electron transport and electron collection. Benefiting from all these merits, the optimized fiber electrode yields unprecedented specific areal capacitance of 1303.6 mF cm-2 (1278 F g-1 based on MnO2, approaching the theoretical value of 1370 F g-1) in liquid KOH and 847.22 mF cm-2 in polyvinyl alcohol (PVA)/KOH gel electrolyte, 2-350 times of previously reported fiber electrodes. The solid-state fiber micro-pseudocapacitors simultaneously achieve remarkable areal energy and power densities of 18.83 µWh cm-2 and 16.33 mW cm-2, greatly exceeding the existing symmetric fiber supercapacitors, together with long cycle life and high rate capability.

| S-EPMC5566233 | biostudies-other

Design and Construction of Cu(OH)2/Ni3S2 Composite Electrode on Cu Foam by Two-Step Electrodeposition.

Project description:A Cu(OH)2/Ni3S2 composite has been designed and in situ constructed on Cu foam substrate by facile two-step electrodeposition. Cu(OH)2 is achieved on Cu foam by galvanostatic electrodeposition, and the subsequent coating of Ni3S2 is realized by cyclic voltammetric (CV) electrodeposition. The introduction of Cu(OH)2 provides skeleton support and a large specific surface area for the Ni3S2 electrodeposition. Benefiting from the selection of different components and preparation technology, the Cu(OH)2/Ni3S2 composite exhibits enhanced electrochemical properties with a high specific capacitance of 4.85 F cm-2 at 2 mA cm-2 and long-term cyclic stability at 80.84% (4000 cycles).

| S-EPMC8878843 | biostudies-literature

Transcriptomic analyses of Lysinibacillus varians GY32 respiring with electrode or oxygen

Project description:This SuperSeries is composed of the SubSeries listed below.

2021-01-29 | GSE165755 | GEO

Retinal Vessel Oxygen Saturation during 100% Oxygen Breathing in Healthy Individuals.

Project description:PurposeTo detect how systemic hyperoxia affects oxygen saturation in retinal arterioles and venules in healthy individuals.MethodsRetinal vessel oxygen saturation was measured in 30 healthy individuals with a spectrophotometric retinal oximeter (Oxymap T1). Oximetry was performed during breathing of room air, 100% oxygen (10 minutes, 6L/min) and then again room air (10 minutes recovery).ResultsMean oxygen saturation rises modestly in retinal arterioles during 100% oxygen breathing (94.5%±3.8 vs. 92.0%±3.7% at baseline, p<0.0001) and dramatically in retinal venules (76.2%±8.0% vs. 51.3%±5.6%, p<0.0001). The arteriovenous difference decreased during 100% oxygen breathing (18.3%±9.0% vs. 40.7%±5.7%, p<0.0001). The mean diameter of arterioles decreased during 100% oxygen breathing compared to baseline (9.7±1.4 pixels vs. 10.3±1.3 pixels, p<0.0001) and the same applies to the mean venular diameter (11.4±1.2 pixels vs. 13.3±1.5 pixels, p<0.0001).ConclusionsBreathing 100% oxygen increases oxygen saturation in retinal arterioles and more so in venules and constricts them compared to baseline levels. The dramatic increase in oxygen saturation in venules reflects oxygen flow from the choroid and the unusual vascular anatomy and oxygen physiology of the eye.

| S-EPMC4456093 | biostudies-literature

Sustainable rose multiflora derived nitrogen/oxygen-enriched micro-/mesoporous carbon as a low-cost competitive electrode towards high-performance electrochemical supercapacitors.

Project description:Cost-efficient carbonaceous materials have been utilized extensively for advanced electrochemical supercapacitors. However, modest gravimetric/volumetric capacitances are the insuperable bottleneck in their practical applications. Herein, we develop a simple yet scalable method to fabricate low-cost micro-/mesoporous N/O-enriched carbon (NOC-K) by using natural rose multiflora as a precursor with KOH activation. The biomass-derived NOC-K is endowed with a large surface area of ∼1646.7 m2 g-1, micro-/mesoporosity with ∼61.3% microporosity, high surface wettability, and a high content of N (∼1.2 at%)/O (∼26.7 at%) species. When evaluated as an electroactive material for supercapacitors, the NOC-K electrode (5 mg cm-2) yields large gravimetric/volumetric specific capacitances of ∼340.0 F g-1 (∼238.0 F cm-3) at 0.5 A g-1, and even ∼200.0 F g-1 (∼140.0 F cm-3) at 5.0 A g-1, a low capacitance decay of ∼4.2% after 8200 consecutive cycles, and a striking specific energy of ∼8.3 W h kg-1 in aqueous KOH electrolyte, benefiting from its intrinsic structural and compositional superiorities. Moreover, a remarkable specific energy of ∼52.6 W h kg-1 and ∼96.6% capacitance retention over 6500 cycles for the NOC-K based symmetric cell are obtained with the organic electrolyte. More promisingly, the competitive NOC-K demonstrates enormous potential towards advanced supercapacitors both with aqueous and organic electrolytes as a sustainable electrode candidate.

| S-EPMC9078741 | biostudies-literature

100 plus years of stem cell research-20 years of ISSCR.

Project description:The International Society for Stem Cell Research (ISSCR) celebrates its 20th anniversary in 2022. This review looks back at some of the key developments in stem cell research as well as the evolution of the ISSCR as part of that field. Important discoveries from stem cell research are described, and how the improved understanding of basic stem cell biology translates into new clinical therapies and insights into disease mechanisms is discussed. Finally, the birth and growth of ISSCR into a leading stem cell society and a respected voice for ethics, advocacy, education and policy in stem cell research are described.

| S-EPMC9213821 | biostudies-literature

S. oneidensis MR-1 with electrode, Fe(III)citrate and oxygen as electron acceptor

Project description:S. oneidensis MR-1 was grown with different electron acceptors: an electrode at 0.4 V vs. SHE, 50 mM Fe(III)citrate, and oxygen. The gene expression pattern for each experiment was analyzed and the differences in gene expression for the different experimental conditions were compared.

2011-02-01 | GSE20379 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data