ChemComm Milestones – Pei-Xi Wang

Congratulations to Pei-Xi Wang who has published his #ChemComm1st article ‘Lyotropic Liquid Crystalline Phases of Anisotropic Nanoparticles of Organic-Inorganic Metal Halide Perovskites: Photoluminescence from Self-Assembled Ordered Microstructures of Semiconductors‘ within the last month. We recently spoke to Pei-Xi about his experiences as a first-time independent author. Find out more in our interview below.

What are the main areas of research in your lab and what motivated you to take this direction?
Motivated by the charming microscopic orderliness of liquid crystalline phases, which provides a relatively simple and controllable bottom-up biomimetic approach to various fascinating hierarchical structures existing in plants and animals, we decided to focus on the development of novel lyotropic liquid crystals as well as the fabrication of functional composite nanomaterials based on them. Currently, we are trying to build a general synthesis method that can transform different types of organic-inorganic metal halide perovskites into colloidal liquid crystalline mesogens, and to further use these semiconducting soft anisotropic materials in optoelectronic devices.

Can you set this article in a wider context?
The functionalization of many types of conventional colloidal liquid crystalline mesogens, such as vanadium pentoxide nanoribbons, polypeptides, and cellulose nanocrystals is usually difficult, i.e., it is hard to endow them with specific energy band gaps or other desired physical properties by chemical modification. In this article, the feasibility of synthesizing mesogenic nanoparticles of organic-inorganic metal halide perovskites has been proven, as metal halide perovskites are a class of materials with excellent structural and compositional diversity, it would be possible to systematically develop a large family of colloidal lyotropic liquid crystals with semiconductivity, luminescence, ferroelectricity, magnetism, chirality, or other preferred features.

What do you hope your lab can achieve in the coming year?
Since late March, my first two graduate students, Ting-Ting Zhou and Cai-Yun Zhao have started to work in the lab. In the coming year, I hope they can find their real research interests either in the field of lyotropic liquid crystalline materials, where I would be able to support them with the experience and knowledge I have gathered during my Ph.D. and postdoctoral studies, or in any other fields attracting them or fortunately initiated by themselves, where they can enjoy the exciting process of making new discoveries every day.

Describe your journey to becoming an independent researcher.
From 2007 to 2009, when I was a student in Henan Experimental High School, I learned a lot of classical and modern physics for the Chinese Physics Olympiad, during which time I was strongly attracted by the conciseness of physical principles such as the Maxwell equations. However, I did not have a clear understanding of scientific research until the completion of my first project under the supervision of Prof. Mark J. MacLachlan (I would also like to acknowledge Dr. Vitor M. Zamarion for his kind help with that project). There was a moment when I accidentally realized that the circular dichroism signal of a chiral nematic mesoporous silica film filled with a Prussian blue analogue should be the product of the absorption and CD spectra of the unfilled film, which was for the first time I noticed that there might be some interesting mathematical relationships behind the seemingly tedious experimental data. From then on, I learned how to build a comprehensive view of the materials and physical phenomena involved in my studies, and started to enjoy the hunt for undiscovered phenomena in the jungle of my experiments.

What is the best piece of advice you have ever been given?
It would be a Chinese saying “吾生也有涯, 而知也无涯, 以有涯随无涯, 殆已”, which means “my lifespan is limited, while knowledge is infinite, spending my limited time on pursuing unlimited knowledge is harmful”.

Why did you choose to publish in ChemComm?
In the past several years, I have been inspired by many classical research articles published in ChemComm, therefore I believe that ChemComm is a great journal for rapidly reporting new chemical discoveries with clear scientific significance and authenticity.

Dr. Pei-Xi Wang was born in China in September 1992. He received his B.Sc. in chemistry from Jilin University in July 2014. He then moved to Vancouver in August 2014 to pursue a Ph.D. and completed his doctorate in chemistry at the University of British Columbia in October 2018, where under the supervision of Prof. Mark J. MacLachlan, he studied the structures and transformation of chiral nematic liquid crystalline tactoidal microphases of cellulose nanocrystals by scanning electron microscopy. Afterwards, he worked as a postdoctoral researcher in the MacLachlan group at UBC (2019/01-2019/12) and in the Edward H. Sargent group at the University of Toronto (2020/01-2020/11). Pei-Xi started his independent research as an associate professor in early December 2020 at the Suzhou Institute of Nano-Tech and Nano-Bionics of the Chinese Academy of Sciences, where he focuses on the development of colloidal lyotropic liquid crystals of semiconducting organic-inorganic metal halide perovskites.

 

Read Pei-Xi’s #ChemComm1st article and others in our growing collection, ChemComm Milestones – First Independent Article. Follow us on Twitter for all of the latest #ChemCommMilestones news.

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ChemComm Milestones – Bartosz Lewandowski

Bartosz Lewandowski’s ChemComm1st article ‘Chiral recognition of amino-acid esters by a glucose-derived macrocyclic receptor‘ is available now. We wanted to find out more about Bartosz and what it was like to reach this ChemComm Milestone in our interview below.

Read our with Bartosz interview here.

What are the main areas of research in your lab and what motivated you to take this direction?
The main topic which we are investigating is the use of monosaccharides as building blocks to create supramolecular receptors and assemblies. We want to take advantage of the intrinsic features of these biomolecules (e.g. water solubility, biocompatibility, modularity) and create new types of supramolecular systems and devices for controlled and selective encapsulation, transport and chemical transformations of molecular entities.

I was “hooked on sugars” during my Ph.D. studies in the group of Prof. Sławomir Jarosz where I explored the chemistry of sucrose. This was a great learning experience for me as I got to know the challenges associated with sugar chemistry, but was also able to appreciate the great potential of these biomolecules. And I felt that there are many exciting things that can be done with sugars, particularly in the context of supramolecular chemistry, which is exactly what we are working on right now.

Can you set this article in a wider context?
The ability to separate or detect enantiomers of bioactive molecules is of high importance since they very often have vastly different chemical and biological properties. Achieving this goal in aqueous media is particularly relevant if one wants to develop analytical tools for diagnostic or therapeutic purposes. Within our manuscript we demonstrated the efficacy of a simple glucose-based macrocycle for differentiation of amino-acid enantiomers in aqueous environments. Thus our results open up exciting opportunities for the development of molecular tools for chirality sensing and enantiomer separation of bioactive molecules.

What do you hope your lab can achieve in the coming year?
Firstly, I hope that we can build on the results we just published and develop further carbohydrate-based chiral receptors. We plan to utilize the modularity of monosaccharides and their potential for functional fine-tuning to create supramolecular receptors with additional attractive features (e.g. increased chemoselectivity, fluorescence). My other ambition for this and following years is to explore other research pathways with carbohydrate-based macrocycles and use them as building blocks to create novel functional supramolecular assemblies and perhaps even molecular machines.

Describe your journey to becoming an independent researcher.
I think the moment when I started to seriously consider becoming an academic researcher was when I joined the group of Prof. David Leigh for my post-doc. Designing and creating molecular machines is a tremendous scientific challenge. But for me it also contained an element of pure joy and excitement coming from assembling small molecular fragments piece-by-piece into a device that can perform complex tasks. And the satisfaction when the final goal was achieved rewarded all the difficulties and frustration that came along the way. And that’s when I thought “Yes, this is what I want to do in life.” That thought was then reinforced when I joined the group of Prof. Helma Wennemers. Working on highly multidisciplinary cutting-edge research and being immediately entrusted with supervision and guidance for junior co-workers (both students and Ph.D. students) allowed me to greatly mature as a scientist. It also inspired me to create my own research plan for the future. And at the end of 2015 I successfully applied for the position of a Senior Scientist in the Wennemers Group at the Laboratory of Organic Chemistry, ETH Zürich. This is a unique position which gives me the opportunity to build my independent research line while remaining an integral part of Prof. Wennemers’ team where we pursue exciting research projects.

What is the best piece of advice you have ever been given?
I’ve been very fortunate to have worked with many incredibly supportive people and I’ve received a lot of great advice from them. The two pieces that stuck with me the most over the years are:
“If you keep doing excellent work, good things will eventually come your way.” and “You should never talk yourself out of an experiment.”

Why did you choose to publish in ChemComm?
First of all because it’s one of the leading chemistry journals in the world with a broad impact on the scientific community. It’s also among my favourite journals to read when I screen recent literature. Finally, I was very keen on publishing my first independent work in ChemComm as this is where the most significant results of my PhD were published.

Bartosz Lewandowski was born in Kętrzyn, Poland in 1981. He obtained his M.Sc. degree in Chemical Technology from the Warsaw University of Technology in 2004. He carried out his Ph.D. research on synthesis and complexing properties of sucrose-based macrocycles in the Institute of Organic Chemistry, Polish Academy of Sciences in Warsaw, in the group of Prof. Sławomir Jarosz. He successfully defended the Ph.D. thesis in 2009 and in the same year became the FNP (Foundation for Polish Science) Post-Doctoral Fellow in the group of Prof. David Leigh at the University of Edinburgh. There he worked on the design, synthesis and operation of molecular machines. In 2013 he joined the group of Prof. Helma Wennemers at the ETH Zürich as a Marie Curie Post-Doctoral Fellow, working on oligoproline-based macrocycles and supramolecular assemblies for molecular recognition and catalysis. In 2016 he was appointed as a Senior Scientist in the Wennemers Group. His research focuses on using monosaccharides to create supramolecular receptors and assemblies for selective binding, transport and chemical transformations of guest molecules.

Read Bartosz’s ChemComm1st article and others in our collection ChemComm Milestones – First Independent Article. Follow @ChemCommun for all of the latest journal and #ChemCommMilestones news.

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ChemComm Milestones – Ellen Robertson

We are pleased to let you know that Ellen Robertson has reached a ChemComm Milestone with her #ChemComm1st article: ‘Synthesis and characterization of plasmonic peptoid nanosheets‘.

Find out about Ellen and her research below.

What are the main areas of research in your lab and what motivated you to take this direction?
I’m a physical chemist by training and my research specifically focuses on colloid and interfacial science. In my lab, we are working to develop new classes of surface enhanced Raman scattering sensors based on the co-assembly of two-dimensional peptoid scaffolds and nanoparticles at fluid surfaces. Our goal is to use these sensors to detect environmental pollutants that are prevalent in Upstate New York. I’ve always been interested in using chemistry to solve environmental problems. In college, I worked on a service-learning project in my introductory chemistry course in which we collected soil and water samples from the community and tested them for lead. I realized from this example how chemistry can be used for the good of the environment and its inhabitants, and it is my aim as a chemist to do this kind of good.

Can you set this article in a wider context?
The research presented in this article clearly demonstrates how the power of interfacial self-assembly can be implemented to fabricate new nanomaterials with interesting properties. I believe the method described in the paper for forming plasmonic peptoid nanosheets can likely be extended to creating two-dimensional arrays of magnetic, semiconducting, antibacterial, and catalytic nanoparticles. This generalizable strategy has the potential for creating a new class of two-dimensional nanomaterials that have a wide range of optical, electronic, and magnetic properties.

What do you hope your lab can achieve in the coming year?
In the upcoming year, my lab hopes to test the limits of our peptoid-directed assembly mechanism for forming new two-dimensional nanomaterials. We are planning to see if we can fine-tune the properties of these nanosheets by varying the nanoparticle concentration, size, surface chemistry, and material used in the synthesis.

Describe your journey to becoming an independent researcher.
My journey to becoming an independent researcher was the result of my love of chemistry and some timely opportunities that I was able to pursue. I started my research path as an undergraduate at Kalamazoo College. I worked in Jeff Bartz’s lab studying the gas phase dissociation of NOx compounds. Jeff encouraged me to pursue summer research opportunities, and I was grateful to have the opportunity to work for one summer at Dartmouth College making cobalt nanoparticles in Barney Grubb’s lab, and one summer at the University of Oregon studying interfacial assembly in Geraldine Richmond’s lab. I loved the Richmond lab research so much, I returned as a graduate student to complete my Ph.D. research, which focused on understanding the assembly of polyelectrolytes at the oil-water interface using vibrational sum frequency spectroscopy (VSFS) and interfacial tension measurements. While in graduate school, I worked on collaborative project between Geri’s lab and Ron Zuckermann’s lab at Lawrence Berkeley National Lab in which I characterized peptoid monolayers using VSFS. The aim of these studies was to assign spectroscopic signatures to peptoid monolayers that were capable of forming peptoid nanosheets via monolayer compression and collapse. Working on this collaboration was a great experience and prompted me to apply for and accept a postdoctoral position in Ron’s lab. I spent two years working in Ron’s lab using interfacial tension and rheology to determine the factors that affect the ability of different peptoid sequences to form monolayers capable of collapse into nanosheets. Following my postdoctoral appointment, I returned to Kalamazoo College as a Visiting Assistant Professor of Chemistry. It was here that I realized my love of working with undergraduates in the research lab, and so I sought out a position at a primarily undergraduate institution. Now an Assistant Professor of Chemistry at Union College, my independent research combines elements of my graduate research (self-assembly at the oil-water interface) with my post-doctoral research (using peptoids to create new materials).

What is the best piece of advice you have ever been given?
Some of the best advice that I have ever been given is to embrace a growth mindset. With a growth mindset, we can always envision new ways to improve, both professionally and personally. Failure no longer becomes an obstacle, but an opportunity to learn something new and grow.

Why did you choose to publish in ChemComm?
I chose to publish in ChemComm because this journal is well known for publishing novel research that is of immediate and broad interest to those in the field of chemistry. I was so excited when my lab discovered the plasmonic peptoid nanosheets described in our recent ChemComm publication. I realized that the synthesis of these novel materials through peptoid monolayer collapse at the oil-water interface opened the door for creating a brand-new class of two-dimensional nanomaterials. I wanted to share this discovery with a broad audience of chemists that could see the utility in these new materials and the method used to prepare them. I am grateful for the opportunity that ChemComm has given me to share my science story.

Back: Ellen Robertson, Chris Avanessian, Anna Mahony, Elizabeth Whitney
Front: Misty Zaczyk, Mindle Shavy Paneth, Jana Davis

Professor Ellen J. Robertson received her Ph.D. in physical chemistry at the University of Oregon where she studied the assembly of polyelectrolytes at the oil-water interface using vibrational sum frequency spectroscopy. Ellen then held a post-doctoral appointment at Lawrence Berkeley National Lab where she studied the assembly mechanism of peptoid nanosheets at the air-water interface. After serving as a Visiting Assistant Professor of Chemistry at Kalamazoo College for two years, Ellen was hired as an Assistant Professor of Chemistry at Union College, a small private liberal arts institution in Upstate New York. Here, she has established her research program, the overall goal of which is to develop peptoid-based surface enhanced Raman scattering sensors for detecting pollutants that are persistent in Upstate New York. Her work has been funded by The Community Foundation for the Greater Capital Region’s Bender Scientific Fund. Ellen is dedicated to undergraduate education in chemistry, both in the classroom and in the research lab. At Union, Ellen teaches courses in general and physical chemistry and works with undergraduates in her research lab. She also co-advises Union College’s American Chemical Society Student Chapter. Outside of chemistry, Ellen is an avid tennis player, competing both at the local and national level. 

You can find all of our #ChemComm1st articles in ChemComm Milestones – First Independent Articles. Follow @ChemCommun for all of the latest ChemComm Milestones updates.

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HOT article: Plug-and-play aqueous electrochemical atom transfer radical polymerization

Paul Wilson and colleagues at University of Warwick, UK, recently published their Communication on a simplified ‘plug-and-play’ approach to aqueous electrochemical atom transfer radical polymerization. In this video Paul gives more detail about the team’s work.


View the open access article ‘Plug-and-play aqueous electrochemical atom transfer radical polymerization’ here

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ChemComm Milestones – Bogdan Barz

We are delighted to bring our latest ChemComm Milestones interview. This time, we would like to highlight Bogdan Barz’s #ChemComm1st article: Compact fibril-like structure of amyloid β-peptide (1–42) monomers.

Read our interview with Bogdan below.

What are the main areas of research in your lab and what motivated you to take this direction?
The focus of my group is on modeling intrinsically disordered proteins, their aggregation into highly
stable fibrils and their interaction with inhibitory peptides. One of the main aims is to quantify
protein-protein interaction and establish a direct connection to experiments. Therefore, a strong
collaboration with experimental groups is of high value. The motivation behind the research path
my group pursues is highly related to the work I did during my Ph.D., where I encountered free
energy calculation methods for the first time, but also to my later work on modeling amyloid
proteins and their self assembly. As an independent researcher I plan to combine these two topics
and make sure that my research is well anchored in experimental observations.

Can you set this article in a wider context?
The amyloid beta protein is a key protein in the onset of Alzheimer’s disease but its precise role is
not understood yet. Therefore, one should study all aspects and stages of aggregation into toxic
oligomers and fibrils in order to have a comprehensive understanding of its complex role in
Alzheimer’s disease. The monomers are the smallest species along the assembly process and
their structural diversity is a hot topic of research. Experimentally, it is difficult to study them due to
the fast aggregation into fibrils, especially for the amyloid β-protein 1-42 (Aβ42). Computationally,
there are many studies directed at monomers, generally with diverging conclusions, but there are
high hopes in the modern force fields specifically tailored for intrinsically disordered proteins. What
makes our study special is the finding that the structural features of the monomer model resemble
those of peptides from fibrillar structures, which is an important piece of the big puzzle. This study
explains to some degree the strong propensity of the Aβ42 monomers to aggregate into a specific
type of fibrils.

What do you hope your lab can achieve in the coming year?
Studying the structural flexibility of the Aβ42 monomer is only the first step of this project. We are
currently working on elucidating the interaction of the monomer with amyloid fibrils in a quest to
understand the relevant factors that contribute to the secondary nucleation of the amyloid beta
protein. My first Ph.D. student, Soumav Nath, is an excellent experimentalist and has already
performed many experiments planned for this project under the supervision of Prof. Alexander K.
Büll from the Technical University of Denmark. Soumav has also learned to perform molecular
dynamics simulations and is now responsible for a large part of the computational work. For the
rest of the year we will finalize the computational part of the project, corroborate the results with the
experiments and publish several related manuscripts. The funding for my group will end this fall,
but we are hoping for a more permanent status in the future.

What is the best piece of advice you have ever been given?
I always remember Dr. Nicolae Aldea’s advice that in science, as in other areas, working with
people is the most difficult task and treating co-workers with respect is what makes a great
research team.

Why did you choose to publish in ChemComm?
I find ChemComm a great journal for the diversity of topics and scientific methods used in its
published papers, but also for its fast publication process. This is my second time publishing in
ChemComm and, based on my previous experience, I can confirm that the journal has great
visibility and the published work has good chances to be cited in further studies.

Dr. Bogdan Barz is a junior group leader at the Heinrich-Heine-Universität in Düsseldorf, Germany. He received his B.S. in Physics and his M.Sc in Applied Mathematics, Mechanics and Astronomy at Babe -Bolyay University in Cluj-Napoca, Romania where he ș focused on topics in magnetohydrodynamics under the supervision of Conf. Dr. Marcu Alexandru. During his masters studies he also worked as a research scientist at the National Institute for Research and Development of Isotopic and Molecular Technologies Cluj-Napoca, Romania in the field of X-ray
spectroscopy under the guidance of Dr. Nicolae Aldea. Afterwards, he started his graduate studies at the University of Missouri, Columbia, USA in the group of Prof. Ioan Kosztin where he received his Ph.D. in Physics working on various topics in computational biophysics. He then pursued a postdoctoral position at Drexel University in Philadelphia, USA in the group of Prof. Brigita Urbanc
where he applied computational methods to study protein aggregation. This position was followed by a postdoctoral fellowship at the Research Centre Jülich, Germany in the group of Prof. Birgit Strodel where Dr. Barz used various computational techniques to describe the self-assembly process of amyloid proteins. Currently, his group, funded by a grant from the German Research Foundation, works in close collaborations with experimental researchers and combines enhanced sampling techniques with free energy methods to quantify protein-protein interaction.

 

Read more #ChemComm1st articles in our growing collection ChemComm Milestones – First Independent Articles. Follow us on Twitter for more #ChemCommMilestones news.

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A cradle for stable cysteine sulfenic acids

How can you study an unstable biomolecule? One research team’s answer to this is to surround it in a protective cradle. The molecules in question here are cysteine sulfenic acids (Cys-SOH); although they are crucial in various cellular processes and biological functions, they have proven elusive for isolated small-molecule studies due to their instability. Researchers in Japan have now reported the first synthesis and isolation of a stable small molecule cysteine sulfenic acid by employing a protective cradle for the reactive Cys-SOH unit. This bio-inspired design mimics the supramolecular protein environments that can stabilise Cys-SOH residues in situ.

Chemical structure of the small molecule cradled Cys-SOH, with the cradle highlighted in teal

Figure 1. The chemical structure of the protective cradle for cysteine-derived reactive intermediates, including Cys-SOH (framework in blue, cysteine in black).

The researchers utilised the m-phenylene dendrimer framework from their previous studies as the molecular cradle to encapsulate cysteine intermediates for further study (Figure 1). A cysteine unit was first installed into the framework (denoted as Bpsc) via the central benzoyl group to generate the cysteine thiol residue, Cys-SH. The cradled Cys-SH was then converted to the cysteine sulfenic acid by treatment with H2O2, to give the isolable small molecule Cys-SOH (compound 6). The cysteine sulfenic acid 6 proved to be air and thermally stable, and the researchers characterised 6 using NMR and IR spectroscopies, as well as X-ray crystallographic analysis that definitively revealed its structure (Figure 2).

Crystal structure showing the connectivity of the cradled Cys-SOH

Figure 2. The crystal structure of the isolated Cys-SOH small molecule 6, cradled by the Bpsc framework (in green).

Once the structure of the cradled cysteine sulfenic acid 6 was established, the researchers investigated its biologically relevant reactivity. The reaction of Cys-SOH with a thiol is important for redox regulation and protein folding, and the researchers observed that 6 did indeed react with the thiol N-acetylcysteine methyl ester to yield the expected disulfide product. Although this reaction initially proved slow, the researchers were able to show that this was not due to steric hinderance from the Bpsc cradle. Optimisation of this reaction revealed that the addition of triethylamine significantly enhanced the reactivity, and this suggests that the presence of basic residues in the vicinity of cysteine sulfenic acids are important for biological disulfide formations.

In addition to the disulfide formation, the researchers also investigated the reactivity of their cysteine sulfenic acid 6 towards reduction and trapping experiments. The Cys-SOH 6 could be reduced by DTT (dithiothreitol) to regenerate the Cys-SH thiol residue, demonstrating the reversibility of the redox processes between Cys-SH and Cys-SOH within the cradle. The researchers also looked at trapping the Cys-SOH residue using various chemical probes to mimic trapping experiments used for protein-generated cysteine sulfenic acids. They observed the expected formation of the thiol adducts, and again noticed enhanced reactivity in the presence of triethylamine.

Overall, the researchers have demonstrated the first example of an isolable and stable cysteine sulfenic acid that is enabled by a cradling framework. The protective cradle was shown to not impact the biologically-relevant reactivity of the Cys-SOH residue, and ultimately, this framework could serve as a useful biorepresentative model for future studies on Cys-SOH to further understand its behaviour.

 

To find out more, please read:

Isolable small-molecule cysteine sulfenic acid

Tsukasa Sano, Ryosuke Masuda, Shohei Sase and Kei Goto*

Chem. Commun., 2021, 57, 2479-2482

 

About the blogger:

Photograph of the author, Samantha AppsDr. Samantha Apps recently finished her post as a Postdoctoral Research Associate in the Lu Lab at the University of Minnesota, USA, and obtained her PhD in 2019 from Imperial College London, UK. She has spent the last few years, both in her PhD and postdoc, researching synthetic nitrogen fixation and transition metal complexes that can activate and functionalise dinitrogen. Outside of the lab, you’ll likely find her baking at home, where her years of synthetic lab training has sparked a passion in kitchen chemistry too.

 

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ChemComm Milestones – Cédric Colomban

This week, we bring you our ChemComm Milestones interview with Cédric Colomban who recently published his #ChemComm1st article. Read ‘A tris(benzyltriazolemethyl)amine-based cage as a CuAAC ligand tolerant to exogeneous bulky nucleophiles‘ in our First Independent Article collection.

Here’s our interview with Cédric:

What are the main areas of research in your lab and what motivated you to take this direction?
My lab, the Bioinspired Confined Catalysis group (BCC), was established in 2020 and is interested in caged bioinorganic complexes for efficient and selective catalytic transformations in confined spaces. Since my Msc’s studies I am amazed by the fascinating reactivity of the nature’s catalysts that are enzymes (and in particular metalloproteins). My research interests have always been inspired by these systems with (i) artificial models reproducing their active sites (PhD on bioinspired catalysts), and (ii) receptors inspired by their tridimensional architectures (postdocs on supramolecular cages). In this line, the BCC group merges these approaches to develop bioinorganic confined catalysts.

Can you set this article in a wider context?
Due to its broad range of applications (chemical biology, material science, interlocked structures), the Cu-catalyzed azide-alkyne cycloaddition reaction (CuAAC) is the most popular transformation of the “click chemistry” toolbox. Many efforts have been devoted to assisting ligands that improve the reaction efficiency and, among them, the tris(benzyltriazolemethyl)amine TBTA has been the most widely used CuI-coordinating structure. However, the recent emergence of CuAAC biorthogonal chemistry has revealed the ongoing need for catalysts that remain active in complex mixtures, such as living systems, where they have to face the competition of bulky CuI-chelators (mainly reduced gluthathione GSH). In this context, the challenge is to develop CuAAC-ligands tolerant to exogeneous bulky nucleophiles such as biothiols.
In this work, we get inspiration from the enzyme hydrophobic pockets, to reach an efficient protection of the TBTA-Cu(I) active core. The canonical ligand was equipped with a bowl-shaped cap to yield the first TBTA-based organic cage. We demonstrate that our shielded ligand remarkably protect the Cu-center from it deactivation by GSH, without suffering from product inhibition effect, opening the way to efficient CuAAC transformations in complex media.

What do you hope your lab can achieve in the coming year?
Findings and funding! First of all, like every research team, I am hoping to return to easier working conditions and to be allowed to attend conferences. This will help the students to keep growing as researchers, and to develop research-networks. Various exciting findings have been recently made in the BCC group regarding Cu and Fe-catalysis and we hope that theses preliminary results will became groundbreaking discoveries. In particular, I am hoping to continue our pioneering research in the field of Bioinspired Confined Catalysis, thanks to funded projects.

Describe your journey to becoming an independent researcher.
After finishing my Msc in bio-organic and bio-inorganic chemistry at the University Grenoble-Alpes, I completed my Ph.D. studies (University of Lyon, France) on bioinspired homogeneous catalysis using porphyrin-like diiron complexes (A. Sorokin group, IRCELYON). After this experience with “open” models, I chose to pursue my research in the field of supramolecular cages and host-guest interactions, and undertook my 1st postdoc on self-assembled cages at the University of Girona, Spain (M. Costas and X. Ribas group, IQCC). Having explored the field of multicharged metallacages, I then decided to focus on purely organic receptors and I completed a 2nd postdoc in the A. Martinez group (Ecole centrale of Marseille, iSm2, France). Finally, in 2020, I was ranked 1st at the highly competitive French-CNRS recruitment contest and become independent researcher at the institute of molecular sciences of Marseille, iSm2, France (BCC group).

What is the best piece of advice you have ever been given?
When I was a PhD student I once asked my supervisor (Alexander Sorokin) if I could try one particular experiment, and his answer was: “Cédric, if we are doing this job, it is to try everything we want!”. Behind these worlds the idea was: important discoveries often arise from unusual experiments, and researchers should pursue their weird ideas without being afraid of failure. As a mentor I am now applying this advice by encouraging students’ creativity.

Why did you choose to publish in ChemComm?
Being a leading journal in general chemistry, and having short format articles, ChemComm has always been part of my favorite journals as a reader. As an author, ChemComm present the advantage of fast publication time and high impact. The journal was therefore perfectly suited to this work that aims at delivering one key message: CuAAC transformations in complex media could be achieved thanks to caged-ligands.

Cédric was born in Briançon, France, in 1986, and obtain a Msc in bio-organic and bio-inorganic chemistry from the University Grenoble-Alpes. He completed his Ph.D. studies (University of Lyon, France) on bioinspired catalysis in 2014, at the IRCELYON institute, under the guidance of Drs. A. Sorokin and P. Afanasiev. He undertook his 1st postdoc with Profs. M. Costas and X. Ribas at the University of Girona, Spain (2015-17), on self-assembled cages and dynamic host-guest interactions. After a second postdoc (2018-19) on organic cages in the group of Prof. A. Martinez (Ecole centrale of Marseille, iSm2, France); he obtains, in 2020, a position of CNRS researcher and started the Bioinpired Confined Catalysis group at the institute of molecular sciences of Marseille, France (iSm2). His group focuses on the preparation and applications of caged bioinorganic complexes. Twitter : @Dr_Colomban_Ced

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ChemComm Milestones – Sheng-Heng Chung

Sheng-Heng Chung published his #ChemComm1st article this year. We were excited to hear that Sheng-Heng had chosen our journal for the home of his first independent research article. You can read his urgent research here: Lean-electrolyte lithium–sulfur electrochemical cells with high-loading carbon nanotube/nanofiber–polysulfide cathodes.


Find out more about Sheng-Heng in our interview below.

What are the main areas of research in your lab and what motivated you to take this direction?
We are a newly-established young research group from September 2019. Our group mainly focuses on the electrochemical conversion and storage technology, such as rechargeable batteries, supercapacitors, and fuel cells. In the department of Materials Sciences and Engineering, our team further works on the scientific studies, in terms of the new energy materials and their electrochemistry, and the engineering designs, in terms of the device components and their fabrication processes. The motivation in conducting this research aims to build up an integrated electrochemical conversion and storage system featuring high energy/power density and long operation life.

Can you set this article in a wider context?
Focusing on the future energy-storage technology, our group is now systemically studying the battery electrochemistry and performance development to develop the lithium-sulfur battery with high energy density. The overall goal of this research article is to propose a new concept in designing a lean-electrolyte lithium-sulfur battery featuring a high amount of the active material, which is necessary to realize a high-energy-density lithium-sulfur battery. Moreover, we apply the designed lean-electrolyte lithium-sulfur battery as a testing platform to demonstrate the importance to investigate the discharge/charge efficiency and low-rate performance for a long cycle life to ensure the stabilization of the conversion-type active material with solid and liquid states in the sulfur cathode. With a more reliable lithium-sulfur battery cathode, we will overcome the scientific/technical challenges by realizing high sulfur loading/content with limited excess lithium in a lean electrolyte cell.

What do you hope your lab can achieve in the coming year?
The publication of our group’s first research article in a high-ranking journal, ChemComm, in 2021 is an exciting achievement for a one-year-old research group. Since our group is still at an early stage, our team aims to establish a solid foundation in our electrochemistry and energy materials research. Our group also welcomes the cooperation and extension of our present researches to support the research and design community.

Describe your journey to becoming an independent researcher.
The time during my undergraduate and Masters at National Cheng Kung University (with Professor Hsing-I Hsiang) and from National Tsing Hua University (with Professor Jau-Ho Jean) in Taiwan gave me wonderful friendships with many laboratory equipments. My experience at the University of Texas at Austin (with Professor Arumugam Manthiram) educated me in conducting research experiments and proposals. I had the opportunity to mentor several graduate and undergraduate students in the lab during this time. These two experiences inspire me to become an independent researcher to deal with research facilities and share knowledge to future scientists.

What is the best piece of advice you have ever been given?
Treat every day as the last day.

Why did you choose to publish in ChemComm?
Our group starts from ChemComm because it is a high-impact and renowned journal in our research field in Chemistry and Materials Science. ChemComm provides authors with the fast publication time and good support from the RSC system.

Sheng-Heng Chung obtained his B.S. (2006) in Resources Engineering and in Materials Science and Engineering from National Cheng Kung University and M.S. (2008) in Materials Science and Engineering from National Tsing Hua University in Taiwan. He joined the Materials Science and Engineering PhD program (2015) and worked as a research associate (2019) with Professor Arumugam Manthiram at the University of Texas at Austin. He is currently an assistant professor in the Department of Materials Science and Engineering at National Cheng Kung University. His current research is focused on electrochemical conversion and storage technology.

 

Read Sheng-Heng’s article and others in ChemComm Milestones – First Independent Articles. Follow us on Twitter for more #ChemCommMilestones and #ChemComm1st content.

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How sea anemones inspired material design

What do sea anemones and two-dimensional (2D) carbon-based materials have in common? Sea anemones are predatory marine animals and 2D materials are often used for applications in catalysis and energy storage. Most would assume there is little in common between this obscure pairing, however, researchers in China took inspiration from the unique anatomy of sea anemones (particularly their tentacles that can trap and capture prey) for their design of new 2D hybrid porous carbon materials.

Hybrid 2D carbon-based materials combine the desirable properties of 2D porous carbon materials (large surface area and good electronic conductivity) with additional functional components (e.g. metal ions or inorganic acids), which can enhance and control the properties of the material. However, the construction of hybrid materials is often limited by poor dispersion of the functional component on the carbon structure, as the functional precursors tend to aggregate on the surface, and thus diminish the desired properties for the material. To overcome this undesirable aggregation, the researchers turned to their sea-anemone, bio-inspired strategy, where they used carbon-based molecular brushes as building blocks to imitate tentacles, allowing functional precursors to be trapped within the brush network make the hybrid materials (Figure 1).

Figure 1. (a) A conventional strategy for the construction of 2D hybrid materials, where the functional components are shown to aggregate on the surface. (b) The sea-anemone inspired approach by the researchers, starting from a carbon molecular brush network that traps the functional component (Lewis acids), leading to 2D hybrid materials after carbonization.

The researchers used poly(4-vinylpyridine)-grafted-graphene oxide (GO-g-P4VP) as the molecular brush substrate and carbon source for the creation of their 2D hybrid materials. They created the substrate by covalently grafting a thin layer of poly(4-vinylpyridine) (P4VP) from a single-layer graphene oxide (GO) surface and used microscopy techniques to characterise the resulting materials, where various protuberances were observed on the GO sheets to signify the brushes. Next, the GO-g-P4VP brushes were subjected to various Lewis acids (Co2+ ions, B or P; using either cobalt nitrate, boric acids or phytic acids, respectively). The researchers observed spontaneous chemisorption and immobilisation of the Lewis acids within the brush structure, due to the strong interaction with the Lewis basic pyridine groups of the P4VP chains. Lastly, the material was then carbonized at 800 °C to produce the 2D hybrid porous carbon materials (2DHPCs), functionalised with Co (2DHPC-Co), B (2DHPC-B) or P species (2DHPC-P).

The new 2DHPCs were characterised using microscopy techniques and X-ray diffraction, which confirmed 2D morphologies of the materials, uniform distribution of the Lewis acid species and porous structures. The researchers then demonstrated the potential of these high-porosity and functionalised materials by testing them in applications as oxygen evolution reaction (OER) electrocatalysts or as sulfur hosts within Li-S batteries, where in both cases, the 2DHPCs excelled compared to other graphene-based materials. Ultimately, the researchers have demonstrated that their sea-anemone inspired strategy allows for the successful construction of high performance 2D hybrid materials, and could be translated for the design of promising new materials for future energy conversion and storage applications.

 

To find out more, please read:

A versatile sea anemone-inspired strategy toward 2D hybrid porous carbons from functional molecular brushes

Xidong Lin, Zelin Wang, Ruliang Liu, Shaohong Liu,* Kunyi Leng, He Lou, Yang Du, Bingna Zheng, Ruowen Fu and Dingcai Wu*

Chem. Commun., 2021, 57, 1446–1449

 

About the blogger:

Photograph of the author, Samantha AppsDr. Samantha Apps recently finished her post as a Postdoctoral Research Associate in the Lu Lab at the University of Minnesota, USA, and obtained her PhD in 2019 from Imperial College London, UK. She has spent the last few years, both in her PhD and postdoc, researching synthetic nitrogen fixation and transition metal complexes that can activate and functionalise dinitrogen. Outside of the lab, you’ll likely find her baking at home, where her years of synthetic lab training has sparked a passion in kitchen chemistry too.

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ChemComm Milestones – Ariel Furst

Congratulations to Ariel Furst on achieving her first ChemComm Milestone. We are excited to bring you our interview with Ariel discussing her #ChemComm1st article: ‘Covalent capture and electrochemical quantification of pathogenic E. coli

Read more below.

What are the main areas of research in your lab and what motivated you to take this direction?
The Furst lab combines biological and chemical engineering with electrochemistry to address challenges in human health and clean energy. We develop new technologies to detect pathogens, combat antimicrobial resistance, degrade environmental pollutants, and improve clean energy technologies. We are motivated by the most pressing global problems: lack of inexpensive, easy-to-use sensors and diagnostics for low-resource settings and dearth of accessible clean energy technologies. Watch our video for more info: https://ilp.mit.edu/watch/ariel-furst

Can you set this article in a wider context?
E. coli are dangerous pathogens, strains of which are responsible for both foodborne illnesses and urinary tract infections (UTIs). According to the USDA, each year, foodborne illnesses impact nearly 50 million Americans, leading to over 100,000 hospitalizations, with an economic cost of over 15 billion dollars. Worldwide, these illnesses cause over 400,000 deaths annually, with a disproportionate impact on children. Preventative measures are critical to prevent these infections and improve patient outcomes. Similarly, E. coli-based UTIs are some of the most common infections, and current diagnostics necessitate centralized facilities and multiple days for diagnosis. Thus, clinicians often prescribe broad-spectrum antibiotics without knowledge of the infectious agent, which leads to recurrent infections and emergent resistances: an exacerbation of both the individual and global problems. We have developed an inexpensive, disposable electrochemical sensor to selectively capture E. coli and accurately quantify them. This technology is a major step toward the implementation of point-of-care and point-of-contamination sensing of these deadly bacteria.

What do you hope your lab can achieve in the coming year?
The Furst Lab is continuing to develop technology to sense dangerous pathogens. We plan to continue to develop diagnostic technologies to detect not only the strain present but also antibiotic resistances in an integrated platform. We are additionally expanding our sensing targets to include the degradation and detection of small-molecule environmental contaminants. We hope to have prototypes of these platforms by the end of the year.

What is the best piece of advice you have ever been given?
Over the years many advisors and mentors have given me great advice, but at the end of the day it’s something that we all learn at a young age, the golden rule: treat others like you would like to be treated. This simple truth extends to all aspects of life and research and ensures that we have an inclusive environment that we can all thrive in.

Why did you choose to publish in ChemComm?
With interdisciplinary work, it is important to reach a wide audience. ChemComm reaches a broad audience and is a great place to share this work. Additionally, the format, a communication, is a great way to share new and exciting work quickly.

Dr. Ariel L. Furst is an Assistant Professor of Chemical Engineering at the Massachusetts Institute of Technology. She received a B.S. degree in Chemistry from the University of Chicago working with Prof. Stephen B. H. Kent to chemically synthesize proteins. She then completed her Ph.D. with Prof. Jacqueline K. Barton at the California Institute of Technology developing new electrochemical diagnostics based on DNA charge transport. She continued her training as an A. O. Beckman Postdoctoral Fellow in the Francis Group at the University of California, Berkeley. The Furst Lab combines electrochemical methods with biomolecular and materials engineering to address challenges in human health and environmental sustainability. Follow Ariel on Twitter: @afurst1, @FurstLab

Read Ariel’s #ChemComm1st article and others in ChemComm Milestones – First Independent Articles. Follow the hashtags on our Twitter.

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