New handheld device detects unwanted trace chemicals
Improvements to chemical sensing chip aims to quickly and accurately identify drugs and other trace chemicals.
University at Buffalo researchers are reporting an advancement of a chemical sensing chip that could lead to handheld devices that detect trace chemicals — everything from illicit drugs to pollution — as quickly as a breathalyzer identifies alcohol.
The chip, which also may have uses in food safety monitoring, anti-counterfeiting and other fields where trace chemicals are analyzed, is described in a study that appears on the cover of the Dec. 17 edition of the journal Advanced Optical Materials.
“There is a great need for portable and cost-effective chemical sensors in many areas, especially drug abuse,” says the study’s lead author Qiaoqiang Gan, PhD, professor of electrical engineering in the UB School of Engineering and Applied Sciences.
The work builds upon previous research Gan’s lab led that involved creating a chip that traps light at the edges of gold and silver nanoparticles.
When biological or chemical molecules land on the chip’s surface, some of the captured light interacts with the molecules and is “scattered” into light of new energies. This effect occurs in recognizable patterns that act as fingerprints of chemical or biological molecules, revealing information about what compounds are present.
Because all chemicals have unique light-scattering signatures, the technology could eventually be integrated into a handheld device for detecting drugs in blood, breath, urine and other biological samples. It could also be incorporated into other devices to identify chemicals in the air or from water, as well as other surfaces.
The sensing method is called surface-enhanced Raman spectroscopy (SERS).
While effective, the chip the Gan group previously created wasn’t uniform in its design. Because the gold and silver was spaced unevenly, it could make scattered molecules difficult to identify, especially if they appeared on different locations of the chip.
Gan and a team of researchers — featuring members of his lab at UB, and researchers from the University of Shanghai for Science and Technology in China, and King Abdullah University of Science and Technology in Saudi Arabia — have been working to remedy this shortcoming.
The team used four molecules (BZT, 4-MBA, BPT, and TPT), each with different lengths, in the fabrication process to control the size of the gaps in between the gold and silver nanoparticles. The updated fabrication process is based upon two techniques, atomic layer deposition and self-assembled monolayers, as opposed to the more common and expensive method for SERS chips, electron-beam lithography.
The result is a SERS chip with unprecedented uniformity that is relatively inexpensive to produce. More importantly, it approaches quantum-limit sensing capabilities, says Gan, which was a challenge for conventional SERS chips
“We think the chip will have many uses in addition to handheld drug detection devices,” says the first author of this work, Nan Zhang, PhD, a postdoctoral researcher in Gan’s lab. “For example, it could be used to assess air and water pollution or the safety of food. It could be useful in the security and defense sectors, and it has tremendous potential in health care.”
The work was supported by the U.S. National Science Foundation.Contacts and sources:
Cory Nealon
Nan Zhang, Haifeng Hu, Matthew Singer, Kuang‐hui Li, Lyu Zhou, Boon S. Ooi, Qiaoqiang Gan. Advanced Optical Materials, 2020; 8 (24): 2001634 DOI: 10.1002/adom.202001634
Source: http://www.ineffableisland.com/2021/01/quantum-limit-approaching-chemical.html
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Joseph Olson
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“Government is like fire, a dangerous servant and fearful master” ~ quoteinvestigator(.)com
All technology is DUAL USE, and it takes little imagination to turn advances into EVIL
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Dev
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Agree Joseph Olson, and that being the case there is clearly no requirement for government.
One of my favourite books available for free, presents a blueprint for life without coercion.
https://cdn.mises.org/The%20Market%20for%20Liberty_2.pdf
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Robert Beatty
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The basic problem is top-down government. This is the most common form where those who are ‘born to rule’ tell the majority of the population what to do. Oh yes, there are mandatory periodic elections to overcome, by fair means or foul, but apart from that things run pretty smoothly for the policy makers.
The alternative is a bottom-up form of government. The Swiss system of direct democracy is one example of this, but the main feature of this form of government is that IT UNLOCKS THE COMBINED INTELLIGENCE OF THE WHOLE POPULATION. The government is allowed to govern, but each policy is open to community scrutiny, and review if found to be unsupported by the population majority. To make this work there needs to be compulsory voting for all the eligible community members, and the system needs to use modern IT methods such as block chain to ensure voting accuracy. My suggestion for an Australian system is at The Australian Constitution
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Robert Beatty
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Link is at https://bosmin.com/Section128.pdf
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Carbon Bigfoot
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My understanding of blockchain is that its enormous power consumption will fry most power grids, especially in Australia, Germany & the UK if utilized on Election Day!!
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Jerry Krause
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Hi PSI Commenters and PSI Readers,
PSI was founded to be a Scientific Forum which question the scientific idea known as the greenhouse effect of atmospheric carbon dioxide. A man by the name of Galileo wrote a book which introduced a ‘new’ field of learning which we now simply term SCIENCE.
Galileo’s book, as translated to English any Crew and de Salvio, began: “The constant activity which you Venetians display in your famous arsenal suggests to the studious mind a large field for investigation, especially that part of the work which involves mechanics; for in this department all types of instruments and machines are constantly being constructed by many artisans, among whom there must be some who, partly by inherited experience and partly by their own observations, have become highly expert and clever in explanation.”
Cory alerts us to a ‘new’ invention (device) which allows scientist to ‘detect’ that which could could not be seen before. But you seem to ignore what we might learn by a use of this new device as you begin to discuss current events which have little to do with SCIENCE. (Experimental philosophy as termed by Newton in his well known, but seldom read, book). Just as Galileo’s well known book is seldom read by current scientists; who only seem to argue and debate like the philosophers of old whose wrong reasoned ideas Galileo demonstrated by observations and experiments to be absolutely wrong.
This comment is an attempt to bring your attention back to the GIFT that Galileo gave us who still claim to be experimental philosophers. For I have read that male dogs evidently have a ‘natural’ sense of smell (device) which allows them to detect a female dog in ‘heat’ from a considerable distance.
Have a good day, Jerry
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