Well-known cause of frequent failures of closed oxygen sensors is the appearance of gas bubbles in the electrolyte. The problem is traditionally associated with insufficient sealing of the sensor that is not always true. Study of a typical temperature regime of measurement system based on Clark sensor showed that spontaneous release of the gas phase is a natural effect caused by periodic warmin...

Soft-lithography and plasma etching with reactive ions were used to fabricate a polymer microfluidic cell-culture bioreactor with integrated optical oxygen sensor. Platinum(II) octaethylporphyrin ketone (PtOEPK) suspended in a microporous polystyrene (PS) matrix was spin-coated to form sensor films of variable thickness from 1.1 μm to 400 nm on glass substrates. Sensor films were found to be sm...

Gas Sensors In article number 2302219, Suk Yeop Chun, Young Geun Song, Chong-Yun Kang, Jung Ho Yoon, and co-workers propose a hysteretic “chemi-memristive gas sensor” based on oxygen-vacancy chemi-memristive dynamics that differ from of conventional sensors. Based the advantageous functionality sensor, including fast responses, short recovery times, response, device-level olfactory systems can ...

Bone tissue engineering (BTE) utilizing biomaterial scaffolds and human mesenchymal stem cells (hMSCs) is a promising approach for the treatment of bone defects. The quality of engineered tissue is crucially affected by numerous parameters including cell density and the oxygen supply. In this study, a novel oxygen-imaging sensor was introduced to monitor the oxygen distribution in three dimensi...

Oxygenation in tissue scaffolds continues to be a limiting factor in regenerative medicine despite efforts to induce neovascularization or to use oxygen-generating materials. Unfortunately, many established methods to measure oxygen concentration, such as using electrodes, require mechanical disturbance of the tissue structure. To address the need for scaffold-based oxygen concentration monitor...

We report the development of a new fluorescence sensor for reactive oxygen species (ROS) based on a benzofurazan structure. The sensor, NBFhd, is initially non-fluorescent and reacts with peroxyl radicals by hydrogen transfer in an aqueous medium under neutral conditions to release the fluorescent N-methyl-4-amino-7-nitrobenzofurazan (NBF) and 1,4-benzoquinone. NBFhd shows excellent contrast an...

A class of core-shell nanoparticles possessing a layer of biocompatible shell and hydrophobic core with embedded oxygen-sensitive platinum-porphyrin (PtTFPP) dyes is developed via a radical-initiated microemulsion co-polymerization strategy. The influences of host matrices and the PtTFPP incorporation manner on the photophysical properties and the oxygen-sensing performance of the nanoparticles...

Oxygen sensors play a vital role in ensuring the safety of employees and users at National High Magnetic Field Laboratory. While most oxygen have accurate linear responses nitrogen/argon environments, studies highlighted phenomenon helium-air mixtures with certain types sensors. A controlled experiment was performed to observe behavior two sensors: orifice membrane. The sensor showed large devi...