Author: aac14026

Insight into Molecular Makeup at UConn’s NMR Facility

Director of UConn's NMR facility, Vitaliy Gorbatyuk.
Director of UConn's NMR facility, Vitaliy Gorbatyuk. (Carson Stifel/UConn Photo).

Right now, there are atoms and molecules inside everything around you. These tiny particles of matter may seem insignificant as you go about your everyday life. But for many scientists and researchers, understanding the compounds that make up the materials they are working with can be critical.

At the University of Connecticut, the Nuclear Magnetic Resonance (NMR) facility provides instrumentation that can identify compounds produced by chemists, biologists, or extracted from natural products.

NMR is a technique used to gain insight into the building blocks, composition, and spacing of atoms in a molecule. The equipment used in this process is called a nuclear magnetic resonance spectrometer. In NMR, a solution of a compound is placed inside a very strong magnet. In this magnetic environment, nuclei of atoms gain properties that allow them to absorb the electromagnetic fields applied to probe these nuclei. Once the nuclei return from the excited state to the ground state they emit the absorbed energy. There are radio antennas inside of the instrumentation that detect the radio-frequency signals which the nuclei radiate. The emitted signals make up a frequency chart (spectrum) characteristic of the compound placed in the magnet.

With approximately 150 active, registered users, the facility directly supports and impacts research programs in the following areas: chemical synthesis, pharmaceutical chemistry, molecular recognition and drug binding, macromolecules, nanomaterials, analysis of chemical mixtures, protein structure-function relationships, protein folding and design, nucleic acid structure and reactivity, and molecular dynamics.

Instead of analyzing samples for prospective users, the facility director, Vitaliy Gorbatyuk, Ph.D., trains scientists to utilize the instrumentation on their own.

“I am glad that I can train researchers to use this equipment because often the skills they gain at this facility can help them later on in their careers. Their mastery of the NMR spectrometers here can provide a foundation for them to become skilled at using even more advanced types of instrumentation in the future,” says Gorbatyuk.

The facility houses multiple spectrometers, including: Varian INOVA 600 MHz, Bruker AVANCE 500 MHz, Bruker AVANCE III 400 MHz, and Bruker AVANCE 300 MHz. Gorbatyuk has years of experience in the field of NMR spectrometry that allow him to be of great help to the users of this facility. In 2001, Gorbatyuk came to the United States as a researcher, and used NMR techniques to work on projects in structural biology related fields. He began working at UConn’s NMR facility ten years ago.

The facility is part of the university-wide Partnership for Excellence in Structural Biology and maintains collaborative ties with its sister NMR facility at UConn Health in Farmington. It is jointly operated by the Department of Chemistry and as part of the Center for Open Research Resources and Equipment (COR2E).

The services and equipment of the UConn NMR Facility are also available to industry and other academic institutions.

Gorbatyuk can be reached at or by phone at 860.486.4069.

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Story Courtesy of UConn Today

Pinkhassik Group on cover of Chemical Communications


Pinkhassik Group on Cover of Chem Comm

A paper from the Pinkhassik Group was featured on the cover of Chemical Communications. Drs. Sergey Dergunov and Eugene Pinkhassik -- working with collaborators from Saint Louis University -- uncovered evidence for freely diffusing ground-state atomic oxygen, an elusive species whose existence in solution was proposed by never proven. This study used hollow porous nanocapsules developed in the Pinkhassik Group to physically separate the donor and acceptor of an oxygen atom. Photochemical reactions in the presence of a nanometer-thin porous barrier ruled out direct oxygen atom transfer mechanisms and, for the first time, confirmed the formation of diffusing atomic oxygen. Previously produced in the gas phase, atomic oxygen is an extraordinary reactive oxygen species; it is highly reactive like hydroxyl radical, yet selective like singlet oxygen or ozone. Evidence for atomic oxygen in solution provides new insights into the mechanisms of many oxidation reactions, facilitates the search for synthetically viable sources of atomic oxygen, and lays the groundwork for studying the controlled release of small oxidants from photoactivatable precursors.

For further details, read the paper in ChemComm

Remembering Professor Ulrich T. Mueller-Westerhoff Ph.D.

Professor UlrichDear Colleagues and Students,

With sadness I must report news about one of our colleagues.

Emeritus Professor Ulrich T. Mueller-Westerhoff, Ph.D., passed away after a brief illness on January 30, 2019 in Storrs, CT. He was born in Wuppertal, Germany, and grew up in Austria and Germany. After studies in chemistry at the Universities in Marburg and Munich, he received his Ph.D. from the University of Darmstadt in 1967. A postdoctoral stay at the University of California at Berkeley where he firstly synthesized uranocene was followed by employment at the IBM Research Station in Almaden, California. He transitioned back to academia when he moved to the University of Connecticut as Head of the Department of Chemistry in 1982. He was a Guest Professor at the University of Bern, University of Würzburg, and the Max-Planck Institute for Polymer Research. He was awarded an Alexander-von-Humboldt Foundation Senior US Scientist Award. He achieved emeritus status at UConn in 2002.

His research field in organometallic chemistry encompassed theoretical aspects of the bonding in sandwich complexes, the chemistry of metallocenophanes, and the utilization of metallodithiolenes. He prepared the last nickel metallodithiolene complex as a laser dye in the emeritus lab in 2017. In support of undergraduate research activities in chemistry, Ulli established the Mueller-Westerhoff Scholarship fund at the University of Connecticut, and many undergraduates have been, and continue to be, supported throughout the summers and the academic year. His sharp intellect, pointed opinions, and generous friendship will be missed.

Services are private.

Christian Brückner

A Better Way to Make Acrylics

acrylic cube
Acrylics and the closely related acrylates are the building blocks for many kinds of plastics, glues, textiles, dyes, paints, and papers. Now researchers from UConn and ExxonMobil describe a new process for making acrylics that would increase energy efficiency and reduce toxic byproducts. (Getty Images)

Acrylics are an incredibly diverse and useful family of chemicals used in all kinds of products, from diapers to nail polish. Now, a team of researchers from UConn and ExxonMobil describe a new process for making them. The new method would increase energy efficiency and reduce toxic byproducts, they report in the Feb. 8 issue of Nature Communications.

The global market for acrylic acid is enormous. The world used close to 5 million metric tonnes of it in 2013, according to industry group PetroChemicals Europe. And no wonder, for acrylics and the closely related acrylates are the building blocks for many kinds of plastics, glues, textiles, dyes, paints, and papers. Strung together in long chains, they can make all kinds of useful materials. Acrylate mixed with sodium hydroxide, for example, makes a super absorbent material used in diapers. Add extra methyl groups (carbon plus three hydrogens), and acrylate makes plexiglass.

The current industrial process for making acrylics require high temperatures close to 450 F, and produce unwanted and sometimes harmful byproducts, such as ethylene, carbon dioxide, and hydrogen cyanide.

UConn chemistry Steve Suib, director of the University's Institute for Materials Science, and colleagues at UConn and ExxonMobil have designed a new way of making acrylics at mild temperatures. Their technique can be finely tuned to avoid producing unwanted chemicals.

"Scientists at ExxonMobil Research & Engineering partnering with professors Suib's group in UConn have been probing new technologies that can lower energy intensity, skip steps, improve energy efficiency, and reduce CO2 footprint in the production process of acrylics," says Partha Nandi, a chemist at ExxonMobil. "The recent publication in Nature Communications describes discovery of a new route to produce a class of acrylate derivatives in potentially fewer steps and with less energy"

The technique uses a porous catalyst made of manganese and oxygen. Catalysts are materials used to speed up reactions. Often, they provide a surface for the molecules to sit on while they react with each other, helping them to meet up in the right configurations to do the deed. In this case, the pores fill that role. The pores are 20 to 500 Angstroms wide, big enough for fairly large molecules to fit inside. The manganese atoms in the material can trade their electrons with nearby oxygens, which makes it easier for the right chemical reactions to happen. Depending on the starting ingredients, the catalyst can facilitate all different kinds of acrylics and acrylates, with very little waste, Suib says.

"We hope this can be scaled up," he says. "We want to maximize yield, minimize temperature, and make an even more active catalyst," that will help the reaction go faster. The group also found adding a little bit of lithium helped speed things up, too. They are currently studying the exact role of lithium, and experimenting with ways of improving the manganese and oxygen catalyst

This research was funded by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical, Biological, and Geological Sciences under grant DE-FG02-86ER13622.A000, as well as ExxonMobil

Article Courtesy of UConn Today

Artificial Skin Could Give Superhuman Perception

hand touching skin on shoulder

A new type of sensor could lead to artificial skin that someday helps burn victims ‘feel’ and safeguards the rest of us, University of Connecticut researchers suggest in a forthcoming paper in Advanced Materials.

Our skin’s ability to perceive pressure, heat, cold and vibration is a critical safety function that most people take for granted. But burn victims, those with prosthetic limbs, and others who have lost skin sensitivity for one reason or another, can’t take it for granted, and often injure themselves unintentionally.

Chemists Islam Mosa from UConn, and James Rusling from UConn and UConn Health, along with University of Toronto engineer Abdelsalam Ahmed, wanted to create a sensor that can mimic the sensing properties of skin. Such a sensor would need to be able to detect pressure, temperature and vibration. But perhaps it could do other things too, the researchers thought.

“It would be very cool if it had abilities human skin does not; for example, the ability to detect magnetic fields, sound waves, and abnormal behaviors,” said Mosa.

Mosa and his colleagues created such a sensor with a silicone tube wrapped in a copper wire and filled with a special fluid made of tiny particles of iron oxide just one billionth of a meter long, called nanoparticles. The nanoparticles rub around the inside of the silicone tube and create an electric current. The copper wire surrounding the silicone tube picks up the current as a signal. When this tube is bumped by something experiencing pressure, the nanoparticles move and the electric signal changes. Sound waves also create waves in the nanoparticle fluid, and the electric signal changes in a different way than when the tube is bumped.

The researchers found that magnetic fields alter the signal too, in a way distinct from pressure or sound waves. Even a person moving around while carrying the sensor changes the electrical current, and the team found they could distinguish between the electrical signals caused by walking, running, jumping, and swimming.

Metal skin might sound like a superhero power, but this skin wouldn’t make the wearer Colossus from the X-men. Rather, Mosa and his colleagues hope it could help burn victims “feel” again, and perhaps act as an early warning for workers exposed to dangerously high magnetic fields. Because the rubber exterior is completely sealed and waterproof, it could also serve as a wearable monitor to alert parents if their child fell into deep water in a pool, for example.

“The inspiration was to make something durable that would last for a very long time, and could detect multiple hazards,” Mosa says. The team has yet to test the sensor for its response to heat and cold, but they suspect it will work for those as well. The next step is to make the sensor in a flat configuration, more like skin, and see if it still works.

Among the authors of the paper are Esraa Elsanadidy and Mohamed Sharafeldin from UConn, and Islam Hassan from McMaster University and Prof. Shenqiang Ren from State University of New York at Buffalo. This work is supported by National Institute of Health (NIH), National Science Foundation (NSF) and US. Department of Energy.

Story Courtesy of UConn Today

Art at the Mall

Art at the Mall

On December 18, 2018, The Chronicle featured Kumar Group's NanoArt display at the Windham Regional Art Gallery. The front-page article, "Art at the Mall," highlighted the Jumar Group's display, as well as the work of other local artists. The NanoArt collection showcases colored electron microscope images that capture proteins in a new light. "The art aspects of this is nature's art. We're trying to connect the signs, and the art bridges that," says Kumar.

Full Story Here

Doctoral students Anka Rao and Megan Puglia, Professor Challa Vijaya Kumar, and doctoral sutdents Mensi Malhotra and Jingwen Ding

International Space Station Research Aims to Treat Blindness

Internaltional Space Station Research Aims to Treat Blindness

On Tuesday, December 4th, a product of a UConn Chemistry start-up will be launching into space on the SpaceX CRS-16! With the support of a 2016 MassChallenge CASIS/Boeing Award, a retinal implant developed by LambdaVision will be the subject of research conducted by the International Space Station (ISS) U.S. National Laboratory. As the ISS orbits the Earth, the retinal implant will be studied to examine the effects of microgravity in layer-by-layer manufacturing.

LambdaVision is the produce of the research group of Dr.Robert Birdge (Harold S. Schwnek Sr. Distinguished Chair Emeritus; Founder of LambdaVision), Dr. Nicole Wagner (Assistant Research Professor; CEO), and Dr.  Jordan Greco (Assistant Research Professor; CSO)

VIDEO: Assistant Research Professors Nicole Wagner & Jordan Greco dicscuss the ISS U.S. National Laboratory Retinal Implant Project

VIDEO: Water the launch live on NASA TV

Energy Storage & Isotope Determinations: An Interdisciplinary Success Story

Dr. Angeles-Boza with Dr. Johannes Barth and Dr. Julien Bachmann
Left to rights: Dr. Johannes Barth (University of Erlangen), Dr. Julient Bachmann (University of Erlangen), and Dr. Alfredo Angeles-Boza (University of Connecticut)

Alfredo Angeles-Boza is featured in a Nature Research: Chemistry Community article for his recent work with energy storage and kinetic isotope effects that contributed to a publication in Nature Communications.

"Interdisciplinary work can be frustrating - scientists in related, yet distinct, fields often have distinct educational backgrounds and may consider different aspects of a given research problem as important. Moreover, they often use different languages, which impedes efficient communication. Despite these caveats, I have long enjoyed the exchange of ideas and methods with specialists of sciences related to chemistry and worked with physicists, biologists, material scientists, and engineers. Discovering novel and unexpected opportunities offered by the combination of various methods is a satisfaction reserved to someone willing to work in interdisciplinary collaborations..." -Julien Bachmann, Professor, University of Erlangen

To read the full Chemistry Community article, click here

To read the Nature Communications publication, click here

A Copper Bullet for Tuberculosis

Bacteria Mycobacterium TuberculosisTuberculosis is a sneaky disease. The bacteria hide from antibiotics inside the very immune cells that are supposed to kill them, making treatment long and difficult. But in the November issue of ACS Infectious Diseases, UConn chemists report a new antibiotic that can find and kill tuberculosis bacteria where they hide.

Tuberculosis is the number one cause of death from infectious disease worldwide. About 25 percent of people on the planet are currently infected. Most of those infections will stay dormant, but one in 10 will become active, infectious, and often fatal if untreated.

Tuberculosis is caused by a bacteria called Mycobacterium tuberculosis. Because of Mycobacterium’s unique lifestyle, in which they allow themselves to be eaten by macrophage immune cells and then grow inside of them, they are very hard to treat. People infected with tuberculosis must typically take a cocktail of antibiotics diligently over many months, because the bacteria are only susceptible to the drugs when they break out of the macrophage in which they were born and search out a new one to invade.

UConn chemist Alfredo Angeles-Boza and his then-graduate student, Daben Libardo, and colleagues from the Indian Institute of Science, the Max Planck Institute, and MIT, decided to make an antibiotic that could make its way into the macrophages and hit the Mycobacteria where they hide. Angeles-Boza and Libardo had previously worked with antibiotics produced by fish, sea squirts, and other sea creatures. Many of these sea creatures make antibiotic peptides – small pieces of protein-like material – with a special chemical talent: when they bind to copper atoms, they enable the copper to shift its electrical charge from +2 to +3 and back. Copper with this ability becomes aggressive, ripping electrons away from some molecules and adding them to others, particularly oxygen-containing molecules. The oxygen-containing molecules become free radicals, dangerous chemicals that attack anything they encounter, including Mycobacteria.

Human macrophages infected with Mycobacteria also use copper to attack the bacteria, but they do so in a less sophisticated way. They trap the bacteria in a bubble and then inject copper +1 ions – that is, plain copper atoms with a plus one charge (Cu+) – into the bubble. But the Mycobacteria can handle that. To them, the bubble is a safe haven, and the Cu+ ions are mere annoyances. The bacteria can steal an extra electron from the Cu+ to make it Cu2+. The copper becomes unreactive and safe that way. And when enough Cu2+ surrounds the Mycobacteria, other, more dangerous kinds of copper can’t get close.

Surrounded by defanged copper, “the bacteria can grow in peace. It’s elegant!” says Angeles-Boza. But if Angeles-Boza and Libardo have their way, the copper camouflage will become Mycobacteria’s downfall. If the antibiotic peptides can get close to the bacteria, they can grab onto one of the copper ions and weaponize it. The trick is getting the peptide close to the bacteria.

To do that, the chemists put the peptides into little bubbles similar to the kind cells use to move around packets of protein ingredients and other tasty stuff. When the bacteria snags one for a snack, the peptide works its chemistry and kills it.

The antibiotic peptide developed by Libardo and Angeles Boza effectively kills Mycobacteria living in macrophages in the lab, but they haven’t been able to cure tuberculosis in mice yet – peptide drugs have various problems that make them tricky to use in mammals. The next step in the research is to use the same chemistry in smaller molecules that can be taken as pills like more typical antibiotics.

This research was funded by grants from NSF.

Article by Kim Krieger, Courtesy of UConn Today

Polymorphism in Benzene-1,3,5- Tricarboxamide Supramolecular Assemblies in Water

Dr. Yao Lin, Associate Professor of Chemistry/Polymer Program, and fellow collaborators were recently published in the Journal of the American Chemical Society. Below is a description of the research:

The control of reaching a specifically designed morphology in supramolecular assembly is one of the key aspects for future success in the area of supramolecular materials, As different structures can be formed by different pathways or by a temperature dependent polymorphism, novel strategies have to be established to obtain a desired structure in the resulting materials. Supported by an NSF CAREER grant and the “Research Opportunities in Europe for NSF CAREER Awardees,” Prof. Yao Lin got an opportunity to attack this challenge by working with Prof. Bert Meijer at the Eindhoven University of Technology. Together, they discovered that increased dynamics is required to provide enough flexibility of the system to form defect-free structures in water. Without this flexibility, the assemblies are frozen into a variety of structures that are very similar at the supramolecular level, but less defined at the mesoscopic level.

To read the full article, click here: