PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

A biosensor for measuring extracellular hydrogen peroxide concentrations

A biosensor for measuring extracellular hydrogen peroxide concentrations
2021-03-08
(Press-News.org) Several processes in the human body are regulated by biochemical reactions involving hydrogen peroxide (H2O2). Although it can act as a 'secondary messenger', relaying or amplifying certain signals between cells, H2O2 is generally toxic because of its oxidant character. The latter means that it converts (oxidizes) biochemical molecules like proteins and DNA. The oxidizing property of H2O2 is of potential therapeutic relevance for cancer, though: deliberately causing tumor cells to increase their H2O2 concentration would be a way to destroy them. In light of this, but also for monitoring pathologies associated with H2O2 overproduction, it is crucial to have a means to reliably quantify hydrogen peroxide concentrations in the extracellular environment. Now, Leonardo Puppulin from Nano Life Science Institute (WPI-NanoLSI), Kanazawa University and colleagues have developed a sensor for measuring concentrations of H2O2 in the vicinity of cell membranes, with nanometer-resolution.

The biosensor consists of a gold nanoparticle with organic molecules attached to it. The whole cluster is designed so that it anchors easily to the outside of a cell's membrane, which is exactly where the hydrogen peroxide molecules to be detected are. As attachment molecules, the scientists used a compound called 4MPBE, known to have a strong Raman scattering response: when irradiated by a laser, the molecules consume some of the laser light's energy. By measuring the frequency change of the laser light, and plotting the signal strength as a function of this change, a unique spectrum is obtained -- a signature of the 4MPBE molecules. When a 4MPBE molecule reacts with a H2O2 molecule, its Raman spectrum changes. Based on this principle, by comparing Raman spectra, Puppulin and colleagues were able to obtain an estimate of the H2O2 concentration near the biosensor.

After developing a calibration procedure for their nanosensor -- relating the H2O2 concentration to a change in Raman spectrum in a quantitative way is not straightforward -- the scientists were able to produce a concentration map with a resolution of about 700 nm for lung cancer cell samples. Finally, they also succeeded in extending their technique to obtain measurements of the H2O2 concentration variation across cell membranes.

Puppulin and colleagues conclude that their "novel approach may be useful for the study of actual H2O2 concentrations involved in cell proliferation or death, which are fundamental to fully elucidate physiological processes and to design new therapeutic strategies."

[Background]

Surface-enhance Raman spectroscopy

The biosensor developed by Leonardo Puppulin from Kanazawa University and colleagues is based on a method called surface-enhanced Raman spectroscopy (SERS). The principle derives from Raman spectroscopy, in which differences between the incoming and the outcoming frequencies of laser light irradiated onto a sample are analyzed. The spectrum obtained by plotting the signal strength as a function of frequency difference is characteristic for the sample, which can in principle be a single molecule. Typically, however, the signal coming from one molecule is too weak to detect, but the effect can be enhanced when the molecule is absorbed on a rough metal surface. Puppulin and colleagues applied the technique to (indirectly) detect hydrogen peroxide; their Raman-responsive molecule is a compound called 4MPBE, which is modified when exposed to hydrogen peroxide.

INFORMATION:


[Attachments] See images for this press release:
A biosensor for measuring extracellular hydrogen peroxide concentrations

ELSE PRESS RELEASES FROM THIS DATE:

COVID-19: Biomarkers linked to severe forms of the disease

2021-03-08
A team of researchers from the CHUM Research Centre has identified new biomarkers associated with the severity of COVID-19 in infected patients. Recent scientific literature has shown that the immune response plays a central part in the severity of COVID-19 disease. Understanding the immune responses generated during the course of the disease is therefore essential to determine which patients are at highest risk for serious complications and death from the disease. In a new study published in the Journal of Clinical Investigation, scientists and clinicians led by Dr.?Catherine Larochelle, researcher at the CHUM Research Centre, have ...

Hybrid microbes: Genome transfer between different bacteria strains explored

2021-03-08
Bacteria integrate genetic material from other bacterial strains more easily than previously thought, which can lead to improved fitness and accelerated evolution. This is shown in a recent study by biophysicists at the University of Cologne. The team analysed genome transfer between bacteria of different lineages. The study was published in the journal PNAS. In the experiment, the team brought one strain of bacteria into contact with DNA fragments from another strain. The uptake of foreign genetic material is known as horizontal gene transfer -- in contrast to vertical gene transfer, by which genes are inherited from a parent cell of the same lineage. The results show that ...

Hospital-based violence intervention program engages vulnerable populations

Hospital-based violence intervention program engages vulnerable populations
2021-03-08
DES PLAINES, IL - A Boston violence intervention advocacy program is effectively engaging the client population that hospital-based violence intervention programs (HVIPs) have been designed to support. This is the conclusion of a study titled Boston Violence Intervention Advocacy Program: Challenges and Opportunities for Client Engagement and Goal Achievement, to be published in the March 2021 issue of Academic Emergency Medicine (AEM), a journal of the Society for Academic Emergency Medicine (SAEM). According to the study, HVIPs should consider which types of client needs prove most challenging to address and which novel strategies will engage vulnerable populations not typically targeted by intervention programs. ...

Unique sensor network for measuring greenhouse gases

Unique sensor network for measuring greenhouse gases
2021-03-08
The sensor network MUCCnet (Munich Urban Carbon Column network) consists of five high-precision optical instruments that analyze the sun's light spectra. They measure the concentration of the gases carbon dioxide (CO2), methane (CH4) and carbon monoxide (CO). Since each gas has its own unique spectral "fingerprint", concentrations of these gases can be determined in the columns of air between the instruments and the sun. "By measuring a vertical column of the atmosphere, local disturbances, such as the disproportionate influence of neighboring stacks, can be removed. Therefore, this type of greenhouse gas balancing is considered particularly robust and accurate," says Prof. Jia Chen. Measurements at five locations in and around Munich One of MUCCnet's measurement devices is ...

Study highlights barriers for women and marginalized groups in supramolecular chemistry

2021-03-08
A new study by the international network Women In Supramolecular Chemistry (WISC) has highlighted the equality, diversity and inclusion (EDI) issues faced by women and marginalised groups working within that field. The network has also set out a 'calling in' approach to address these issues. The study, led by Dr Jennifer Leigh and Dr Jennifer Hiscock (both University of Kent) alongside WISC's wider team of international researchers, found that both men and women in the supramolecular community wanted to see more mentoring opportunities and more visibility for women and marginalised groups. There is a desire for more guidance during the transition from postdoctoral researcher to independent Principal Investigator, to ensure women can be retained ...

No more sitting in the dark?

2021-03-08
(COLUMBUS, Ohio) - Concussion, a form of traumatic brain injury, is a common injury among children and teens. Concussions can have adverse effects on physical, cognitive, emotional and sleep health. Clinical guidelines for managing concussion in children and teens traditionally recommend complete physical and cognitive rest until symptom resolution, followed by a gradual return to activities like school and sports. These guidelines are often disputed and based on expert consensus as opposed to strong evidence. The challenge has been how to quantify the amount of physical and cognitive activity that children and teens should engage in during recovery. A new study by researchers at the Center for ...

Latest research delineates the effectiveness of "quitlines" for smoking cessation

2021-03-08
While cigarette smoking continues to be the leading cause of preventable disease, disability and death in the U.S., the evidence base for cessation support has revealed that telephone call centers, or "quitlines," have been a particularly successful intervention, according to the Centers for Disease Control and Prevention (CDC), which recently published a compilation of scientific research in the American Journal of Preventive Medicine. Titled "The Role of Quitlines in Tobacco Cessation," the supplement is composed of nine peer-reviewed articles and three commentaries presenting the latest science on quitlines' effectiveness for smoking termination. The compilation demonstrates the relevance and importance of call ...

Atmospheric drying will lead to lower crop yields, shorter trees across the globe

Atmospheric drying will lead to lower crop yields, shorter trees across the globe
2021-03-08
A global observation of an ongoing atmospheric drying -- known by scientists as a rise in vapor pressure deficit -- has been observed worldwide since the early 2000s. In recent years, this concerning phenomenon has been on the rise, and is predicted to amplify even more in the coming decades as climate change intensifies. In a new paper published in the journal Global Change Biology, research from the University of Minnesota and Western University in Ontario, Canada, outlines global atmospheric drying significantly reduces productivity of both crops and non-crop plants, even under well-watered conditions. The new findings were established on a large-scale analysis covering 50 years of research and 112 plant species. "When there ...

The impact of lockdown drives us to make poorer choices

2021-03-08
Lockdown and other restrictions imposed to control the COVID-19 pandemic have had unseen negative effects on the cognitive capacity and mental health of the population. A study led by the UOC's research group Open Evidence, in collaboration with international universities and BDI Schlseinger Group Market Research, has gauged the impact of the measures taken during the first and second waves of the virus on citizens of three European Union countries. The study concludes that the shock produced by the situation has reduced people's cognitive capacity, leading them to take more risks, ...

A giant, sizzling planet may be orbiting the star Vega

2021-03-08
Astronomers have discovered new hints of a giant, scorching-hot planet orbiting Vega, one of the brightest stars in the night sky. The research, published this month in The Astrophysical Journal, was led by University of Colorado Boulder student Spencer Hurt, an undergraduate in the Department of Astrophysical and Planetary Sciences. It focuses on an iconic and relatively young star, Vega, which is part of the constellation Lyra and has a mass twice that of our own sun. This celestial body sits just 25 light-years, or about 150 trillion miles, from Earth--pretty close, astronomically speaking. Scientists can also see Vega with telescopes even when it's light out, which makes ...

LAST 30 PRESS RELEASES:

Thirty-year mystery of dissonance in the “ringing” of black holes explained

Less intensive works best for agricultural soil

Arctic rivers project receives “national champion” designation from frontiers foundation

Computational biology paves the way for new ALS tests

Study offers new hope for babies born with opioid withdrawal syndrome

UT, Volkswagen Group of America celebrate research partnership

New Medicare program could dramatically improve affordability for cancer drugs – if patients enroll

Are ‘zombie’ skin cells harmful or helpful? The answer may be in their shapes

University of Cincinnati Cancer Center presents research at AACR 2025

Head and neck, breast, lung and survivorship studies headline Dana-Farber research at AACR Annual Meeting 2025

AACR: Researchers share promising results from MD Anderson clinical trials

New research explains why our waistlines expand in middle age

Advancements in muon detection: Taishan Antineutrino Observatory's innovative top veto tracker

Chips off the old block

Microvascular decompression combined with nerve combing for atypical trigeminal neuralgia

Cutting the complexity from digital carpentry

Lung immune cell type “quietly” controls inflammation in COVID-19

Fiscal impact of expanded Medicare coverage for GLP-1 receptor agonists to treat obesity

State and sociodemographic trends in US cigarette smoking with future projections

Young adults drive historic decline in smoking

NFCR congratulates Dr. Robert C. Bast, Jr. on receiving the AACR-Daniel D. Von Hoff Award for Outstanding Contributions to Education and Training in Cancer Research

Chimpanzee stem cells offer new insights into early embryonic development

This injected protein-like polymer helps tissues heal after a heart attack

FlexTech inaugural issue launches, pioneering interdisciplinary innovation in flexible technology

In Down syndrome mice, 40Hz light and sound improve cognition, neurogenesis, connectivity

Methyl eugenol: potential to inhibit oxidative stress, address related diseases, and its toxicological effects

A vascularized multilayer chip reveals shear stress-induced angiogenesis in diverse fluid conditions

AI helps unravel a cause of Alzheimer's disease and identify a therapeutic candidate

Coalition of Autism Scientists critiques US Department of Health and Human Services Autism Research Initiative

Structure dictates effectiveness, safety in nanomedicine

[Press-News.org] A biosensor for measuring extracellular hydrogen peroxide concentrations