Researchers create method for more sensitive electrochemical sensors

Findings could open up a new class of technologies with applications in medicine, chemistry, and engineering

2013-01-17

(Press-News.org) Graphene and related materials hold promise for the future of electrochemical sensors — detectors that measure the concentration of oxygen, toxic gases, and other substances — but many applications require greater sensitivity at lower detection ranges than scientists have been able to achieve.

A Northwestern University research team and partners in India have recently developed a new method for amplifying signals in graphene oxide-based electrochemical sensors through a process called "magneto-electrochemical immunoassay." The findings could open up a new class of technologies with applications in medicine, chemistry, and engineering.

Researchers from Northwestern's McCormick School of Engineering and Applied Science, the Northwestern International Institute for Nanotechnology (IIN), the Northwestern University Atomic and Nanoscale Characterization Experimental (NUANCE) Center, and the Institute for Microbial Technology (IMTECH)-India, a national laboratory of India, contributed to the research.

A paper about the work, "Enhancing Electrochemical Detection on Graphene Oxide-CNT Nanostructured Electrodes Using Magneto-Nanobioprobes," was published November 19 in Nature Scientific Reports.

Graphene-based nanocomposite films have recently been used as an effective sensing platform for the development of electrochemical sensors and biosensors because of their unique facile surface modification characteristics and high charge mobility.

The researchers' new concept combines the advantages carbon nanotubes and reduced graphene oxide together with electrochemical bursting of magnetic gold nanoparticles into a large number of metal ions.

High sensitivity was achieved by precisely designing the nanohybrid and correlating the available metal ions with analyte concentration. The researchers used tiny magnetic particles encapsulated in inert coating of silicon dioxide to make core-shell nanostructures with favorable magnetic properties of metallic iron while preventing them from oxidation or significant degradation. They were then coated with gold because of its chemical inertness and biocompatibility.

This novel immune-detection platform shows potential for rapid and sensitive screening of environmental pollutants or toxins in samples. Researchers reported the ultrahigh sensitivity of this method for a new generation of herbicide diuron and its analogues up to sub-picomolar concentration in standard water samples. The process also proved to be efficient and cost-effective: tens of thousands of screen-printed electrodes can be manufactured quite readily with low cost for such hybrid assay.

### The paper's authors included Vinayak Dravid, professor of materials science and engineering at Northwestern, a founding member of IIN, and director of the NUANCE Center; Gajendera Shekhawat, research associate professor of materials science and engineering at Northwestern; Jinsong Wu, research assistant professor of materials science and engineering at Northwestern; and lead author Priyanka Sharma, Vijayender Bhalla, E. Senthil Prasad, and C. Raman Suri, all of the Institute of Microbial Technology, India.

The National Science Foundation NSF-IREE, NSF-ECCS, and NSF-OISE grant supported this work, with partial support from NIH CCNE program at Northwestern.

ELSE PRESS RELEASES FROM THIS DATE:

Guided care provides better quality of care for chronically ill older adults

2013-01-17

Patients who received Guided Care, a comprehensive form of primary care for older adults with chronic health problems, rated the quality of their care much higher than patients in regular primary care, and used less home care, according to a study by researchers at Johns Hopkins University. In an article published online by the Journal of General Internal Medicine, researchers found that in a 32-month randomized controlled trial, Guided Care patients rated the quality of their care significantly higher than those in normal care, and were 66 percent more likely to rate their ...

New key to organism complexity identified

2013-01-17

The enormously diverse complexity seen amongst individual species within the animal kingdom evolved from a surprisingly small gene pool. For example, mice effectively serve as medical research models because humans and mice share 80-percent of the same protein-coding genes. The key to morphological and behavioral complexity, a growing body of scientific evidence suggests, is the regulation of gene expression by a family of DNA-binding proteins called "transcription factors." Now, a team of researchers with the U.S. Department of Energy's Lawrence Berkeley National Laboratory ...

Hearing-loss-prevention drugs closer to reality thanks to new UF test

2013-01-17

GAINESVILLE, Fla. — A new way to test anti-hearing-loss drugs in people could help land those medicines on pharmacy shelves sooner. University of Florida researchers have figured out the longstanding problem of how to safely create temporary, reversible hearing loss in order to see how well the drugs work. The findings are described in the November/December 2012 issue of the journal Ear & Hearing. "There's a real need for drug solutions to hearing loss," said lead investigator Colleen Le Prell, Ph.D., an associate professor in the department of speech, language, and hearing ...

The new age of proteomics: An integrative vision of the cellular world

2013-01-17

The enormous complexity of biological processes requires the use of highperformance technologies —also known as 'omics'—, that are capable of carrying out complete integrated analyses of the thousands of molecules that cells are made up of, and of studying their role in illnesses. In the post-genomic age we find ourselves in, the comprehensive study of cellular proteins —prote-omics— acquires a new dimension, as proteins are the molecular executors of genes and, therefore, the most important pieces of the puzzle if we wish to understand more completely how cells work. The ...

Implicit race bias increases the differences in the neural representations of black and white faces

2013-01-17

Racial stereotypes have been shown to have subtle and unintended consequences on how we treat members of different race groups. According to new research published in Psychological Science, a journal of the Association for Psychological Science, race bias also increases differences in the brain's representations of faces. Psychological scientists Tobias Brosch of the University of Geneva in Switzerland and Eyal Bar-David and Elizabeth Phelps of New York University examined activity in the brain while participants looked at pictures of White and Black faces. Afterwards, ...

New insights into the 'borderline personality' brain

2013-01-17

New work by University of Toronto Scarborough researchers gives the best description yet of the neural circuits that underlie a severe mental illness called Borderline Personality Disorder (BPD), and could lead to better treatments and diagnosis. The work shows that brain regions that process negative emotions (for example, anger and sadness) are overactive in people with BPD, while brain regions that would normally help damp down negative emotions are underactive. People with BPD tend to have unstable and turbulent emotions which can lead to chaotic relationships with ...

Lack of key enzyme in the metabolism of folic acid leads to birth defects

2013-01-17

AUSTIN, Texas — Researchers at The University of Texas at Austin have discovered that the lack of a critical enzyme in the folic acid metabolic pathway leads to neural tube birth defects in developing embryos. It has been known for several decades that folic acid supplementation dramatically reduces the incidence of neural tube defects, such as spina bifida and anencephaly, which are among the most common birth defects. In some populations, folic acid supplementation has decreased neural tube defects by as much as 70 percent. However, scientists still do not fully ...

New UAlberta research shows commonly prescribed medications could have adverse effects

2013-01-17

A research team with the Faculty of Medicine & Dentistry at the University of Alberta reported findings that significantly improve understanding of how widely used drugs in Pulmonary Arterial Hypertension (PAH) affect the heart health of treated patients. The research shows that medications often prescribed for PAH could block the function of an important hormone in the heart, decreasing the strength of contraction of the right heart chambers, a potentially important and yet unrecognized adverse effect. PAH is a disease that affects the blood vessels of the lungs, causing ...

Novel technique reveals dynamics of telomere DNA structure

2013-01-17

Biomedical researchers studying aging and cancer are intensely interested in telomeres, the protective caps on the ends of chromosomes. In a new study, scientists at UC Santa Cruz used a novel technique to reveal structural and mechanical properties of telomeres that could help guide the development of new anti-cancer drugs. Telomeres are long, repetitive DNA sequences at the ends of chromosomes that serve a protective function analogous to that of the plastic tips on shoelaces. As cells divide, their telomeres get progressively shorter, until eventually the cells stop ...

Diabetic fruit flies support buzz about dietary sugar dangers

2013-01-17

LA JOLLA, Calif., January 15, 2013 – Regularly consuming sucrose—the type of sugar found in many sweetened beverages—increases a person's risk of heart disease. In a study published January 10 in the journal PLOS Genetics, researchers at Sanford-Burnham Medical Research Institute and Mount Sinai School of Medicine used fruit flies, a well-established model for human health and disease, to determine exactly how sucrose affects heart function. In addition, the researchers discovered that blocking this cellular mechanism prevents sucrose-related heart problems. "Our study ...

In small preliminary study, fearful pet dogs exhibited significantly different microbiomes and metabolic molecules to non-fearful dogs, suggesting the gut-brain axis might be involved in fear behavior

Examination of Large Language Model "red-teaming" defines it as a non-malicious team-effort activity to seek LLMs' limits and identifies 35 different techniques used to test them

Most microplastics in French bottled and tap water are smaller than 20 µm - fine enough to pass into blood and organs, but below the EU-recommended detection limit

Researchers create method for more sensitive electrochemical sensors

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: