December 2018 - ACS Axial | ACS Publications

Read the Top Trending 2018 Articles from the ACS Polymer Portfolio

The Altmetric Attention Score gives researchers the ability to view a more organized and comprehensive record of an article’s online shares, while concurrently tracking discussions of a research article’s findings and results. Altmetric Attention Scores reflect a variety of sources, including social media, traditional media (both mainstream and science specific), online reference managers, forums, and Wikipedia. The information is aggregated to produce a score that is a measure of the quality and quantity of attention received by an article, i.e. how an article is “trending”.

ACS Macro Letters, Biomacromolecules, and Macromolecules make up the ACS Publications’ core portfolio of polymer and macromolecular science journals. Where Biomacromolecules publishes research at the unique intersection of polymer science and biology, Macromolecules publishes research on all fundamental aspects of macromolecular science and holds the position as the most-cited original research journal in the field. ACS Macro Letters is the highest-impact original research journal in all of polymer chemistry, and publishes rapid communications that address challenges in biomedicine, energy, sustainability and beyond.

Given the impressive journals that make up this core portfolio, many articles trend well online due to interest in the topics covered. Read the polymer papers from 2018 with the highest Altmetric scores.

ACS Macro Letters

Bulk pH-Responsive DNA Quadruplex Hydrogels Prepared by Liquid-Phase, Large-Scale DNA Synthesis
ACS Macro Lett., 2018, 7 (3), pp 295–299
DOI: 10.1021/acsmacrolett.8b00063
Altmetric Score: 402
Strength of Recluse Spider’s Silk Originates from Nanofibrils
ACS Macro Lett., 2018, 7 (11), pp 1364–1370
DOI: 10.1021/acsmacrolett.8b00678
Altmetric Score: 99
Fast and Efficient Water Absorption Material Inspired by Cactus Root
ACS Macro Lett., 2018, 7 (3), pp 387–394
DOI: 10.1021/acsmacrolett.8b00014
Altmetric Score: 94
Semiconductor Quantum Dots as Photocatalysts for Controlled Light-Mediated Radical Polymerization
ACS Macro Lett., 2018, 7 (2), pp 184–189
DOI: 10.1021/acsmacrolett.7b00968
Altmetric Score: 73
One Methylene Group in the Side Chain Can Alter by 90 Degrees the Orientation of a Main-Chain Liquid Crystal on a Unidirectional Substrate
ACS Macro Lett., 2018, 7 (4), pp 453–458
DOI: 10.1021/acsmacrolett.8b00044
Altmetric Score: 61


Ice Recrystallization Inhibiting Polymers Enable Glycerol-Free Cryopreservation of Microorganisms
Biomacromolecules, 2018, 19 (8), pp 3371–3376
DOI: 10.1021/acs.biomac.8b00660
Altmetric Score: 163
Large and Small Assembly: Combining Functional Macromolecules with Small Peptides to Control the Morphology of Skeletal Muscle Progenitor Cells
Biomacromolecules, 2018, 19 (3), pp 825–837
DOI: 10.1021/acs.biomac.7b01632
Altmetric Score: 82
Reinforcing Mucus Barrier Properties with Low Molar Mass Chitosans
Biomacromolecules, 2018, 19 (3), pp 872–882
DOI: 10.1021/acs.biomac.7b01670
Altmetric Score: 81
Recombinant Spidroins Fully Replicate Primary Mechanical Properties of Natural Spider Silk
Biomacromolecules, 2018, 19 (9), pp 3853–3860
DOI: 10.1021/acs.biomac.8b00980
Altmetric Score: 78
Clinical Evidence for Use of a Noninvasive Biosensor for Tear Glucose as an Alternative to Painful Finger-Prick for Diabetes Management Utilizing a Biopolymer Coating
Biomacromolecules, 2018, 19 (11), pp 4504–4511
DOI: 10.1021/acs.biomac.8b01429
Altmetric Score: 78


Tough, Rapidly Swelling Thermoplastic Elastomer Hydrogels for Hemorrhage Control
Macromolecules, 2018, 51 (12), pp 4705–4717
DOI: 10.1021/acs.macromol.8b00428
Altmetric Score: 358
Imaging Unstained Synthetic Polymer Crystals and Defects on Atomic Length Scales Using Cryogenic Electron Microscopy
Macromolecules, 2018, 51 (19), pp 7794–7799
DOI: 10.1021/acs.macromol.8b01508
Altmetric Score: 55
Synthesis of Alkaline Anion Exchange Membranes with Chemically Stable Imidazolium Cations: Unexpected Cross-Linked Macrocycles from Ring-Fused ROMP Monomers
Macromolecules, 2018, 51 (8), pp 3212–3218
DOI: 10.1021/acs.macromol.8b00209
Altmetric Score: 20
Practical Synthesis of Functional Metathesis Initiators Using Enynes
Macromolecules, 2018, 51 (16), pp 6497–6503
DOI: 10.1021/acs.macromol.8b00866
Altmetric Score: 14
Phase Behavior and Salt Partitioning in Polyelectrolyte Complex Coacervates
Macromolecules, 2018, 51 (8), pp 2988–2995
DOI: 10.1021/acs.macromol.8b00238
Altmetric Score: 13

Accounts Evolves to Meet the Ever-Changing Landscape of Research

Accounts of Chemical Research is a known for publishing concise reports on focused topics from world-renowned experts and is a “go-to” for readers wanting to be broadly educated about the current research frontiers in chemistry and related sciences. Here we have compiled all of the 2018 Special Issues for your reading convenience. Topics include: intermetallic compounds, energy storage, and supramolecular chemistry in confined space and organized assemblies, to name a few.

This Special Issue on Advancing Chemistry through Intermetallic Compounds, guest edited by Daniel Fredrickson and Gordon Miller, emphasizes the synergy within research in the molecular and intermetallic realms, including chemical strides forward in the preparation of unprecedented compounds, the recognition of deeper connections between the bonding and properties of metals and molecules, and the discovery of new reactivity made possible through intermetallic catalysts.

The Special Issue on “Energy Storage: Complexities Among Materials and Interfaces at Multiple Length Scales”, guest-edited by Esther Takeuchi (Stony Brook University) and Marca Doeff (Lawrence Berkeley National Laboratory), investigates electrical energy storage over multiple length scales.

Guest-edited by Polina Anikeeva (Massachusetts Institute of Technology), Charles Lieber (Harvard University), and Jinwoo Cheon (Yonsei University), this Special Issue on “The Interface of Biology with Nanoscience and Electronics” highlights the recent research in bioelectronics and nanomaterials chemistry and the applications in synthetic biology, tissue engineering, and neuroscience.

This Special Issue on “Hydrogen Atom Transfer”, guest-edited by Miquel Costas and Massimo Bietti, presents an overview of the most important aspects and most recent developments of Hydrogen Atom Transfer processes, with the final goal of providing a reference tool for both the practitioner and the newcomer to the field.

Guest-edited by, Vivian Yam (University of Hong Kong), Makoto Fujita (University of Tokyo), and Dean Toste (University of California, Berkeley), this special issue on “Supramolecular Chemistry in Confined Space and Organized Assemblies” presents the many facets of the current challenges and the state-of-the-art approaches in tackling the design principles of supramolecular systems in confined space and organized assemblies of controlled sizes, shapes, and topologies for tuning their properties, functions, and reactivity in diverse areas of catalysis, host–guest chemistry, guest capture and delivery, and emerging materials.

In this Special Issue on “Fundamental Aspects of Self-Powered Nano- and Micromotors”, leading research groups to address fundamental questions and share their latest results in an exciting new field of science. The issue was guest-edited by Ayusman Sen (Pennsylvania State University), Peer Fischer (Max Planck Institute for Intelligent Systems), and Anna Balazs (University of Pittsburgh).

This Special Issue on atomic precision in nanoscience, guest edited by Rongchao Jin, Yong Pei, and Tatsuya Tsukuda, promotes the “atomic precision” concept for nanoscience and highlights recent progress in controlling nanoparticles with atomic precision.


For a look back at Special Issues from previous years as well as a look at topics that will be featured upcoming issues, click here.

Read the Top Trending ACS Chemical Neuroscience Articles of 2018

The Altmetric Attention Score gives researchers the ability to view a more organized and comprehensive record of an article’s online shares, while concurrently tracking discussions of a research article’s findings and results. Altmetric Attention Scores reflect a variety of sources, including social media, traditional media (both mainstream and science-specific), online reference managers, forums, and Wikipedia. The information is aggregated to produce a score that is a measure of the quality and quantity of attention received by an article, i.e. how an article is “trending”.

ACS Chemical Neuroscience publishes high-quality research articles and reviews that showcase chemical, quantitative biological, biophysical, and bioengineering approaches to understanding the nervous system, as well as the development of new treatments for neurological disorders. In 2018, the journal published a special issue titled, “DARK Classics in Chemical Neuroscience,” focusing on the pharmacology, history, and chemistry of illicit drugs. The journal recently published virtual issues and collections on Alzheimers, clinical neuroscience, and more.

Many ACS Chemical Neuroscience articles trend well online due to interest in the topics covered. Read the Top 10 2018 ACS Chemical Neuroscience papers with the highest Altmetric scores.


Sensor Array for Detection of Early Stage Parkinson’s Disease before Medication

ACS Chem. Neurosci., 2018, 9 (11), pp 2548–2553

DOI: 10.1021/acschemneuro.8b00245

Altmetric Score: 159


Clinically Approved Drugs against CNS Diseases as Potential Therapeutic Agents To Target Brain-Eating Amoeb

ACS Chem. Neurosci., Article ASAP

DOI: 10.1021/acschemneuro.8b00484

Altmetric Score: 158


Effects of N,N-Dimethyltryptamine on Rat Behaviors Relevant to Anxiety and Depression

ACS Chem. Neurosci., 2018, 9 (7), pp 1582–1590

DOI: 10.1021/acschemneuro.8b00134

Almetric Score: 77


Zebrafish-Based Discovery of Antiseizure Compounds from the Red Sea: Pseurotin A2 and Azaspirofuran A

ACS Chem. Neurosci., 2018, 9 (7), pp 1652–1662

DOI: 10.1021/acschemneuro.8b00060

Almetric Score: 73


Functionalization and Characterization of Magnetic Nanoparticles for the Detection of Ferritin Accumulation in Alzheimer’s Disease

ACS Chem. Neurosci., 2018, 9 (5), pp 912–924

DOI: 10.1021/acschemneuro.7b00260

Almetric Score: 57


CoREST Complex-Selective Histone Deacetylase Inhibitors Show Prosynaptic Effects and an Improved Safety Profile To Enable Treatment of Synaptopathies

ACS Chem. Neurosci., Article ASAP

DOI: 10.1021/acschemneuro.8b00620

Almetric Score: 47


Dendritic Learning as a Paradigm Shift in Brain Learning

ACS Chem. Neurosci., 2018, 9 (6), pp 1230–1232

DOI: 10.1021/acschemneuro.8b00204

Almetric Score: 30


The DARK Side of Total Synthesis: Strategies and Tactics in Psychoactive Drug Production

ACS Chem. Neurosci., 2018, 9 (10), pp 2307–2330

DOI: 10.1021/acschemneuro.7b00528

Almetric Score: 26


Time-Dependent Alterations in the Expression of NMDA Receptor Subunits along the Dorsoventral Hippocampal Axis in an Animal Model of Nascent Psychosis

ACS Chem. Neurosci., 2018, 9 (9), pp 2241–2251

DOI: 10.1021/acschemneuro.8b00017

Almetric Score: 22

ACS Editors Are Among the World’s Most Cited Researchers

Clarivate Analytics’ 2018 Highly Cited Researchers list includes 94 Editors of ACS journals. The list recognizes the top 1% of researchers by citations in one or more of the 21 fields used in Clarivate Analytics Essential Science Indicators, which include Chemistry and Biology & Biochemistry, but also encompass all other major fields of research.

The list looks at papers published and cited between 2006 and 2016, selecting the top 1% by citations in a field and year. Just 6,000 researchers around the world are included on the list, with 4,000 being named for their work in specific areas and about 2,000 more being included for work across multiple disciplines. This year marks the first time the list has identified researchers with cross-disciplinary impact.

Find out which ACS Editors made the list this year, listed alphabetically first by journal and then by last name.

Accounts of Chemical Research

Jinwoo Cheon, Yonsei University

ACS Applied Bio Materials

Jong Seung Kim, Korea University

ACS Applied Energy Materials

Chunsheng Wang, University of Maryland

ACS Applied Materials & Interfaces

Zhongwei Chen, University of Waterloo

Chunhai Fan, Shanghai Institute of Applied Physics, Chinese Academy of Sciences

Omar K. Farha, Northwestern University

Yu-Guo Guo, Institute of Chemistry, Chinese Academy of Sciences

Zaiping Guo, University of Wollongong, Australia

ACS Applied Nano Materials

Yanli Zhao, Nanyang Technological University

ACS Biomaterials Science & Engineering

David L. Kaplan, Tufts University

Jason A. Burdick, University of Pennsylvania

ACS Catalysis

Sukbok Chang, KAIST

ACS Central Science

Christopher Chang, University of California, Berkley

Dongyuan Zhao, Fudan University 

ACS Energy Letters

Prashant Kamat, University of Notre Dame

Filippo De Angelis, CNR Institute of Molecular Sciences and Technology

Yong-Sheng Hu, Institute of Physics, Chinese Academy of Sciences

Song Jin, University of Madison-Wisconsin

Yang-Kook Sun, Hanyang University

ACS Nano

Warren Chan, University of Toronto

Manish Chhowalla, Rutgers University

Omid Farokhzad, Harvard University

Yury Gogotsi, Drexel University

Paula Hammond, Massachusetts Institute of Technology

Mark Hersam, Northwestern University

Ali Javey, University of California, Berkley

Kazunori Kataoka, The University of Tokyo

Ali Khademhosseini, University of California, Los Angeles

Nicholas Kotov, University of Michigan

Shuit-Tong Lee, Institute of Functional Nano & Soft Materials, Chinese Academy of Sciences

Young Hee Lee, Sungkyunkwan University

Andre Nel, University of California, Los Angeles

Peter Nordlander, Rice University

Wolfgang Parak, University of Hamburg

Andrey Rogach, City University of Hong Kong

Molly Stevens, Imperial College London

ACS Omega

Luis Liz-Marzán, CIC biomaGUNE

ACS Pharmacology & Translational

Patrick Sexton, Monash University

ACS Photonics

Harry Atwater, California Institute of Technology

Edward Sargent, University of Toronto

Romain Quidant, ICFO – The Institute of Photonic Science

Stefan Maier, Imperial College of London

ACS Sensors

Mike Sailor, University of California, San Diego

ACS Synthetic Biology

Christopher Voigt, Massachusetts Institute of Technology


Nathanael Gray, Harvard University

Bioconjugate Chemistry

Vincent Rotello, University of Massachusetts, Amherst


Kristi S. Anseth, University of Colorado, Boulder

Zhiyuan Zhong, Soochow University

Chemistry of Materials

Jean-Luc Bredas, Georgia Institute of Technology

Frank Caruso, The University of Melbourne

Maksym Kovalenko, ETH Zürich

Ferdi Schueth, The Max Planck Institute for Coal Research

Kian Ping Loh, National University of Singapore

Crystal Growth & Design

Michael Zaworotko, University of Limerick

Environmental Science & Technology

Guibin Jiang, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences 

Pedro Alvarez, Rice University

Menachem Elimelech, Yale University

Jorge Gardea-Torresdey, The University of Texas at El Paso

Environmental Science & Technology Letters

Bruce Logan, The Pennsylvania State University

Inorganic Chemistry

Frank Neese, Max Planck Institute for Chemical Energy Conversion

Roberta Sessoli, University of Florence

Hong-Cai Zhou, Texas A&M University

Journal of the American Chemical Society

Phil Baran, The Scripps Research Institute

Benjamin Cravatt, The Scripps Research Institute

Jean M. J. Frechet, University California, Berkley

Taeghwan Hyeon, Seoul National University

Thomas Mallouk, The Pennsylvania State University

Chad Mirkin, Northwestern University

Klaus Muellen, Max Planck Institute for Polymer Research

Melanie Sanford, University of Michigan

Weihong Tan, University of Florida

Li-Jun Wan, Key Laboratory of Molecular Nanostructure and Nanotechnology, Chinese Academy of Sciences

Omar Yaghi, University of California, Berkley

Peidong Yang, University of California, Berkley

Journal of Agricultural and Food Chemistry

Chi-Tang Ho, Rutgers University

Francisco A. Tomas-Barberan, CEBAS-CSIC

Journal of Chemical Theory and Computation

Gustavo Scuseria, Rice University

Journal of Medicinal Chemistry

Hualiang Jiang, Shanghai Institute of Materia Medica, Chinese Academy of Sciences

The Journal of Physical Chemistry A/B/C

George C. Schatz, Northwestern University

Catherine Murphy, University of Illinois

The Journal of Physical Chemistry Letters

Juan Bisquert, Jaume I University

Jin Zhang, University of California, San Diego

Journal of Proteome Research

Jeremy Nicholson, Murdoch University


Thomas P. Russell, University of Massachusetts, Amherst

Nano Letters

A. Paul Alivisatos, University of California, Berkley

Charles M. Lieber, Harvard University

Yi Cui, Stanford University

Naomi Halas, Rice University

Philip Kim, Harvard University

Chun Ning (Jeanie) Lau, The Ohio State University

Hongkun Park, Harvard University

Jiwoong Park, The University of Chicago

Younan Xia, Georgia Institute Technology

Organic Letters

Jin-Quan Yu, Scripps Research Institute

Revamping a Brain Cancer Drug

Glioblastoma—a type of aggressive, invasive brain tumor—is almost always fatal. Although treatments exist, there is no cure. Now, researchers have taken a fresh look at a drug used to treat glioblastoma, temozolomide, and made it a better cancer killer with fewer side effects.

For a long time, the standard of care for glioblastoma treatment was radiation and surgery, which extended patient survival for an average of 12 months, says Paul J. Hergenrother of the University of Illinois, Urbana–Champaign. Since 1999, doctors have also given patients temozolomide, which enhances survival a little.

When temozolomide is activated by water it can add methyl groups to DNA, causing enough genetic damage to kill cells. However, the reaction isn’t specific to tumor cells, so the drug can lead to hefty side effects, especially since only 17% of temozolomide makes it to the brain. The problem is the blood-brain barrier, biological membranes that restrict unwanted substances from infiltrating the brain. Hergenrother’s team wanted to see if they could tweak temozolomide’s structure to help it pass into the brain without compromising its anticancer properties.

“When we started thinking about the chemistry and mechanism of temozolomide, we became curious about why some features of the molecule were there,” Hergenrother says. The team homed in on the molecule’s amide group, which has a large electric dipole—a property that is typically unhelpful in getting drugs through membranes. The synthesis of temozolomide was developed decades ago, and at that time the reaction sequence required a stable precursor that included this amide group, he says. By using modern synthetic chemistry methods, Hergenrother’s team could make the compound with an alternative group in place of the amide, to help the drug pass more easily through the blood-brain barrier while retaining its effectiveness.

To that end, the team systematically swapped out the amide for a series of chemical groups hypothesized to improve brain penetrance and then tested the compounds, first in cancer cells and then in mice. The best performing compound in mice, K-TMZ, contained a methyl ketone instead of the troublesome amide group. K-TMZ showed greatly increased brain permeability, with 69% entering the central nervous system compared with just 8% for temozolomide. In a mouse model of glioblastoma, K-TMZ treatment increased survival indefinitely. The researchers say that they now plan to test the compound in dogs with glioblastoma.

“The work is a tour-de-force of how these medicinal chemical problems need to be addressed,” says Shahriar Mobashery of the University of Notre Dame. He was particularly impressed by the researchers’ “clever chemistry.”

This article is reproduced with permission from C&EN (© American Chemical Society). The article was first published on November 16, 2018.

Making Flower Power by Using Petals and Leaves to Build High-Capacity Electrodes

Under a microscope, the surfaces of many flower petals and plant leaves look like a landscape of bumps and pillars. The tiny structures make water droplets bead up and roll off. They also dramatically increase surface area. By depositing a thin polymer film directly onto these high-area surfaces, researchers have made electrodes that can store a large amount of charge. The electrodes could be used for light, flexible supercapacitors that power wearable gadgets and tiny sensors.

Like batteries, supercapacitors are energy-storing devices made of two electrodes and an electrolyte. But they charge and discharge much faster, providing short bursts of power in vehicles, power tools, and consumer electronics. Conventional supercapacitor electrodes are made of carbon or metal oxides, whereas newer, flexible ones use graphene or conductive polymer electrodes.

One way to increase the charge storage capacity of these devices is to increase the surface area of the electrodes. Researchers have done that before by making conductive films on three-dimensional scaffolds with microscopic features. But the scaffolds have been made using expensive lithography techniques.

“So we thought we’d start with nature,” says Trisha L. Andrew, a chemist and materials engineer at the University of Massachusetts, Amherst. She and her colleague Lushuai Zhang used petals and leaves as scaffolds to make microstructured polymer films.

They used a method that Andrew has developed and used to make solar cells on cloth. It involves injecting thin vapor streams of a monomer and an oxidant perpendicular to each other into a reaction chamber. Where the two vapors intersect, they react and form a polymer that deposits on the substrate placed underneath. The researchers use 3,4-ethylenedioxythiophene as the monomer and iron trichloride as the oxidant, which react to form a porous polymer, poly(3,4-ethylenedioxythiophene), that can store charge.

The duo made 10-µm-thick films on fresh sunflower petals and pressed pansy petals, and also on the dried leaves of lotus plants and fresh leaves of two common household plants: zebra plant (Calathea zebrina) and friendship plant (Pilea involucrata). Lotus leaves are covered with arrays of microscopic pillars; sunflower and pansy petals contain pyramidal structures; and the two houseplant leaves are textured with an assortment of features of different sizes. “Every petal and leaf has various structures exactly on the scale we were looking for, which is a few micrometers,” Andrew says.

Next, the researchers tested supercapacitors made using the microstructured films as electrodes. The high density of large surface features on friendship plant leaves resulted in the highest surface-area films, which led to the highest specific capacity of all of the materials tested of 142 mF/cm2. That’s eight- to 10-fold higher than the best supercapacitor electrodes, which are made of laser-scribed graphene and have capacitance of 4 to 5 mF/cm2.

The devices are robust, showing no physical degradation or loss in capacitance after 10,000 charge-discharge cycles and after being bent and rolled a few hundred times. Laminating the devices in plastic keeps them from breaking down, the researchers found. “I believe this technique can be scaled up and that we can use plant matter in commercial devices,” Andrew says. The use of natural materials and cheap polymers should make them low cost.

Chinedum Osuji, a chemical and biomolecular engineer at the University of Pennsylvania, says that the reactive vapor deposition technology Andrew uses leads to thicker textured polymer films than ones made so far, which also adds to the charge-storing capacity. Plus, the method works under mild conditions. “This is attractive from the perspective of low-cost, facile fabrication of electrochemical energy-storage devices,” he says.

This article is reproduced with permission from C&EN (© American Chemical Society). The article was first published on November 2, 2018.

Reflections on 2018 from Chemical Research in Toxicology

In many ways, this was a year like any other for Chemical Research in Toxicology (CRT), a volume of diverse, exciting, important, rigorous research findings at the intersection of Toxicological Sciences and Chemistry in its 31st year. In other ways, it was a major event, with a new Editor-in-Chief—me!—and a team of Associate Editors coming on board. I am the Professor of Toxicology at the ETH Zurich (Switzerland), and our Associate Editors are Kate S. Carroll (U.S.), Jiayin Dai (China), Annette Kraegeloh (Germany) and Yinsheng Wang (U.S.).

CRT is an extremely important journal for chemistry and toxicology, and it stands on a strong reputation for publishing high-quality science, as well as a having a fair and efficient review process. Along with upholding these strengths of the journal, further aims of the editorial team include expanding the broad scientific scope of CRT, promoting the global nature of our scientific community, and promoting the visibility of the work of CRT authors and highlight timely topics.

The field of toxicology has undergone a major shift in recent years, moving from being an observational to a predictive science. This concept has always been a central aspect of CRT. With advances in systems-oriented and in vitro approaches in toxicology, this concept has become more relevant to broader areas. Reflecting on 2018, I am thankful for how well the editorial team has come up to speed with the daily workings of the journal. This was no easy task, and sometime last winter, I even received a letter suggesting our names on the masthead to be in error! By spring we had really clicked, linking the complementary scientific perspectives, and with a view toward expanding the scientific scope and global perspective, over the last months our wonderful Associate Editors published a series of editorials introducing themselves:

Our team places a high value in the concept that diversity and global perspectives make science better. Not only are we practitioners of research around the globe, but we have deep personal experience in how our own lives and careers have been shaped by multi-national and multi-disciplinary scientific experiences. Our advice to young researchers is to take advantage of opportunities without borders to engage with the CRT community and beyond. We also stress to young researchers and authors new to the CRT community the value of connecting the dots in science: understanding how concepts from different experimental approaches or scientific perspectives, and across different topic areas interconnect.

Looking forward to 2019, a great motivation for me is the high relevance of Toxicology. It allows fundamental scientific knowledge to enable new technologies and make a positive impact on public health and the protection of the environment. This perspective motivated another 2018 highlight for CRT: the creation of ToxWatch. ToxWatch articles pair an eye-catching poster graphic with short, accessible text to explore current issues in toxicology. We were excited that our ToxWatch concept was recently highlighted in an ACS axial series covering topics like these:

Aside from ToxWatch, we have many plans underway for promoting the visibility of outstanding CRT science, such as thematic special issues in 2019 on topics such as “Redox Pathways in Chemical Toxicology” and “Epigenetics in Toxicology.”

In closing, I take the chance to thank the incredible scientific community, authors and reviewers alike, who contribute their hard work and bright ideas to really make the journal. I wish you a peaceful close to 2018 and a spectacular 2019!

Shana J. Sturla
ETH Zurich
Zurich, Switzerland

Protein Captures Lanthanide Traces

Lanthanides were once thought to have no role in biology, but that dogma was shattered when researchers discovered bacteria that rely on these elements to survive. Yet the microbes’ ability to gather highly insoluble lanthanide ions from their environment has remained a puzzle.

Joseph A. Cotruvo Jr. and colleagues at Pennsylvania State University have now discovered a protein that could help to explain how these bacteria harvest scant traces of lanthanides and incorporate them in enzymes. Known as lanmodulin, the protein’s unique structure can bind lanthanide ions from solutions with mere picomolar concentrations and is 100 million times as selective for lanthanides as for calcium ions. The researchers suggest that the protein could inspire systems that detect lanthanides in the environment or pluck them from waste.

“I think it’s beautiful stuff; I’m really excited,” says Eric J. Schelter of the University of Pennsylvania, who studies lanthanide-dependent enzymes and was not involved in the research. These studies are “starting to show how microbes handle lanthanides.”

Cotruvo’s team found the protein while they were studying Methylobacterium extorquens, a bacterium originally found by accident in a University of Oxford laboratory in 1960. The bacterium metabolizes methanol using a methanol dehydrogenase (MDH) enzyme that relies on a lanthanide ion for its activity. The researchers hypothesize that the newly discovered protein may scavenge lanthanides to deliver them to MDH.

Lanmodulin has four so-called EF hands, a feature found in other metal-binding proteins such as calmodulin, which is involved in calcium signaling in all eukaryotic cells. An EF hand’s shape resembles a human hand with thumb and forefinger extended, just as a child would mimic a pistol. Metal ions attach to a binding site in the “palm” of the hand.

The researchers showed that half a dozen different lanthanides, as well as the rare earth yttrium, could bind to three of lanmodulin’s hands at extremely low concentrations. This process makes the protein adopt a much more compact shape, which may enable it to transfer lanthanide ions to MDH in M. extorquens, Cotruvo suggests.

In contrast, it takes millimolar concentrations of calcium ions to trigger this shape-shifting routine. “It has this exquisite selectivity,” says Rachel N. Austin of Barnard College, a metalloprotein expert who was not involved in the research.

Cotruvo’s team used nuclear magnetic resonance (NMR) experiments to study the structure of lanmodulin while it was bound to yttrium ions. “Compared to calmodulin, it’s a totally different structure,” Austin says. For instance, lanmodulin’s two pairs of EF hands are much closer together, and each hand contains a crucial proline residue.

When the researchers swapped these prolines for alanine in an engineered form of lanmodulin, calcium could induce the conformational change at much lower micromolar concentrations. This suggests that the proline residues somehow hamper lanmodulin’s response to calcium and are at least partly responsible for the protein’s selectivity, the researchers say.

Lanthanides are found in technologies from smartphones to lasers, but the chemical similarity of these elements, along with their ions’ insolubility, makes it tough to extract or recycle them. Cotruvo hopes that lanmodulin could help, for example, by teasing lanthanides away from much higher concentrations of calcium, manganese, or iron in mine tailings. “It’s one of the most exciting potential applications for this protein,” he says.

This article is reproduced with permission from C&EN (© American Chemical Society). The article was first published on November 6, 2018.

Watch How Flexible Electronic Skin Could Help Humans and Machines Interact

New research published in ACS Applied Materials & Interfaces reports the development of ultrathin, stretchable electronics that can be easily transferred to 3D objects or made to adhere to human skin. The paper’s authors say these flexible electronics could improve man-machine interfaces in a variety of ways.

The researchers fabricated a ∼5 μm thick circuit by printing the pattern over a temporary tattoo paper using a desktop laser printer. They then coated the circuit with a silver ink and eutectic gallium–indium (EGaIn) liquid metal alloy. The resulting “Ag–In–Ga” traces are highly conductive and maintain low electrical resistivity as the circuit is stretched to conform to nondevelopable 3D surfaces.

The authors write that this material could have a number of practical applications, such as creating an interactive circuit with touch buttons, transferring light-emitting diodes to the 3D-printed shell of a robotic prosthetic hand, making tattoos that could be used to acquire an electromyography signal from human skin, and transferring a proximity measurement skin over a 3D surface.

This video shows how these circuits could be used to help machines and humans interact.