3,758 results match your criteria Accounts of Chemical Research [Journal]


The Prospect of Electrochemical Technologies Advancing Worldwide Water Treatment.

Authors:
Brian P Chaplin

Acc Chem Res 2019 Feb 15. Epub 2019 Feb 15.

Department of Chemical Engineering , University of Illinois at Chicago , 810 S. Clinton Street , Chicago , Illinois 60607 , United States.

Growing worldwide population, climate change, and decaying water infrastructure have all contributed to a need for a better water treatment and conveyance model. Distributed water treatment is one possible solution, which relies on the local treatment of water from various sources to a degree dependent on its intended use and, finally, distribution to local consumers. This distributed, fit-for-purpose water treatment strategy requires the development of new modular point-of-use and point-of-entry technologies to bring this idea to fruition. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00611
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http://dx.doi.org/10.1021/acs.accounts.8b00611DOI Listing
February 2019
5 Reads

Flexible Electronics toward Wearable Sensing.

Acc Chem Res 2019 Feb 15. Epub 2019 Feb 15.

Department of Electrical Engineering and Computer Sciences , University of California , Berkeley , California 94720 , United States.

Wearable sensors play a crucial role in realizing personalized medicine, as they can continuously collect data from the human body to capture meaningful health status changes in time for preventive intervention. However, motion artifacts and mechanical mismatches between conventional rigid electronic materials and soft skin often lead to substantial sensor errors during epidermal measurement. Because of its unique properties such as high flexibility and conformability, flexible electronics enables a natural interaction between electronics and the human body. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00500
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http://dx.doi.org/10.1021/acs.accounts.8b00500DOI Listing
February 2019
1 Read

Mother Knows Best: Deciphering the Antibacterial Properties of Human Milk Oligosaccharides.

Acc Chem Res 2019 Feb 14. Epub 2019 Feb 14.

Department of Chemistry , Vanderbilt University , 7330 Stevenson Science Center , Nashville , Tennessee 37235 , United States.

This Account describes the risky proposition of organizing a multidisciplinary team to interrogate a challenging problem in chemical biology: characterizing how human milk, at the molecular level, protects infants from infectious diseases. At the outset, our initial hypothesis was that human milk oligosaccharides (HMOs) possess antimicrobial and antivirulence activities. Early on, we discovered that HMOs do indeed modulate bacterial growth and biofilm production for numerous bacterial pathogens. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00630DOI Listing
February 2019

Bioinspired Small-Molecule Tools for the Imaging of Redox Biology.

Acc Chem Res 2019 Feb 12. Epub 2019 Feb 12.

School of Chemistry , The University of Sydney , Sydney , NSW 2006 , Australia.

The availability of electrons to biological systems underpins the mitochondrial electron transport chain (ETC) that powers living cells. It is little wonder, therefore, that the sufficiency of electron supply is critical to cellular health. Considering mitochondrial redox activity alone, a lack of oxygen (hypoxia) leads to impaired production of adenosine triphosphate (ATP), the major energy currency of the cell, whereas excess oxygen (hyperoxia) is associated with elevated production of reactive oxygen species (ROS) from the interaction of oxygen with electrons that have leaked from the ETC. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00368
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http://dx.doi.org/10.1021/acs.accounts.8b00368DOI Listing
February 2019
2 Reads

Phase Control in Inorganic Nanocrystals through Finely Tuned Growth at an Ultrathin Scale.

Authors:
Haoyi Li Xun Wang

Acc Chem Res 2019 Feb 12. Epub 2019 Feb 12.

Key Lab of Organic Optoelectronics and Molecular Engineering, Department of Chemistry , Tsinghua University , Beijing 100084 , China.

Crystalline polymorphs have been considered a prevailing phenomenon in inorganic nanocrystals and provide approaches to modulate fundamental properties and innovative advanced applications. As a basic demand for phase engineering, accessible and controllable synthetic methodologies are indispensable for acquisition of high-quality products in expected phases. Phase stability is also a non-negligible issue that determines continuous gains of functionality and long-term sustainability of characteristic features. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00645DOI Listing
February 2019
1 Read

Surface Chemistry-Mediated Near-Infrared Emission of Small Coinage Metal Nanoparticles.

Acc Chem Res 2019 Feb 11. Epub 2019 Feb 11.

Department of Chemistry , University of Pittsburgh , 219 Parkman Avenue , Pittsburgh , Pennsylvania 15260 , United States.

From size-dependent luminescence to localized surface plasmon resonances, the optical properties that emerge from common materials with nanoscale dimensions have been revolutionary. As nanomaterials get smaller, they approach molecular electronic structures, and this transition from bulk to molecular electronic properties is a subject of far-reaching impact. One class of nanomaterials that exhibit particularly interesting optoelectronic features at this size transition are coinage metal (i. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00573DOI Listing
February 2019

Time-Resolved Spectroscopic Observation and Characterization of Water-Assisted Photoredox Reactions of Selected Aromatic Carbonyl Compounds.

Acc Chem Res 2019 Feb 11. Epub 2019 Feb 11.

Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong , P. R. China.

In recent years, unusual and efficient self-photoredox reactions were detected for selected benzophenone derivatives (BPs) and anthraquinone derivatives (AQs) in aqueous environments by Wan and co-workers, where the carbonyl undergoes reduction to the corresponding alcohol and a side-chain alcohol group undergoes oxidation to the corresponding carbonyl. To unravel the photoredox reaction mechanisms of these types of BPs and AQs in aqueous environments, we have utilized a combination of time-resolved spectroscopy techniques such as femtosecond transient absorption, nanosecond transient absorption, and nanosecond time-resolved resonance Raman spectroscopy to detect and characterize the electronic absorption and vibrational spectra of the intermediates and transient species from the femtosecond to microsecond time region after they are generated in the photoredox reactions. With the assistance of density functional theory calculations to simulate the electronic absorption and Raman spectra, the structural and kinetic information on the key reactive intermediates is described. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00619DOI Listing
February 2019

Efficient and Selective Electrochemically Driven Enzyme-Catalyzed Reduction of Carbon Dioxide to Formate using Formate Dehydrogenase and an Artificial Cofactor.

Acc Chem Res 2019 Feb 11. Epub 2019 Feb 11.

Loker Hydrocarbon Research Institute, Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States.

Increasing levels of carbon dioxide in the atmosphere and the growing need for energy necessitate a shift toward reliance on renewable energy sources and the utilization of carbon dioxide. Thus, producing carbonaceous fuel by the electrochemical reduction of carbon dioxide has been very appealing. We have focused on addressing the principal challenges of poor selectivity and poor energy efficiency in the electrochemical reduction of carbon dioxide. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00551DOI Listing
February 2019
1 Read

Artificial Metalloenzymes Based on the Biotin-Streptavidin Technology: Enzymatic Cascades and Directed Evolution.

Acc Chem Res 2019 Feb 8. Epub 2019 Feb 8.

Department of Chemistry , University of Basel , BPR1096, Mattenstrasse 24a , CH-4058 Basel , Switzerland.

Artificial metalloenzymes (ArMs) result from anchoring a metal-containing moiety within a macromolecular scaffold (protein or oligonucleotide). The resulting hybrid catalyst combines attractive features of both homogeneous catalysts and enzymes. This strategy includes the possibility of optimizing the reaction by both chemical (catalyst design) and genetic means leading to achievement of a novel degree of (enantio)selectivity, broadening of the substrate scope, or increased activity, among others. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00618DOI Listing
February 2019
1 Read

Harnessing the Rheological Properties of Liquid Metals To Shape Soft Electronic Conductors for Wearable Applications.

Acc Chem Res 2019 Feb 4. Epub 2019 Feb 4.

Bertarelli Foundation Chair in Neuroprosthetic Technology, Laboratory for Soft Bioelectronic Interfaces, Institute of Microengineering, Institute of Bioengineering, Centre for Neuroprosthetics , École Polytechnique Fédérale de Lausanne (EPFL) , 1202 Geneva , Switzerland.

Emerging applications of the Internet of Things in healthcare, wellness, and gaming require continuous monitoring of the body and its environment, fueling the need for wearable devices able to maintain intimate, reliable, and unobtrusive contact with the human body. This translates in the necessity to develop soft and deformable electronics that match the body's mechanics and dynamics. In recent years, various strategies have been proposed to form stretchable circuits and more specifically elastic electrical conductors embedded in elastomeric substrate using either geometrical structuring of solid conductors or intrinsically stretchable materials. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00489DOI Listing
February 2019

Redox-Switchable Ring-Opening Polymerization with Ferrocene Derivatives.

Acc Chem Res 2019 Feb 1;52(2):415-424. Epub 2019 Feb 1.

Department of Chemistry and Biochemistry , University of California, Los Angeles , 607 Charles E. Young Drive East , Los Angeles , California 90095 , United States.

Switchable catalysts incorporate stimuli-responsive features and allow synthetic tasks that are difficult or impossible to accomplish in other ways. They mimic biological processes in that they can provide both spatial and temporal control, unlike most reactions promoted by human-made catalysts that usually occur according to carefully optimized conditions. In the area of switchable catalysis, redox-switchable ring-opening polymerization (ROP) has attracted much attention, emerging as a powerful strategy for the development of environmentally friendly biodegradable copolymers, especially those containing blocks with complementary properties. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00523
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http://dx.doi.org/10.1021/acs.accounts.8b00523DOI Listing
February 2019
3 Reads

Up to a Sign. The Insidious Effects of Energetically Inaccessible Conical Intersections on Unimolecular Reactions.

Acc Chem Res 2019 Feb 1;52(2):501-509. Epub 2019 Feb 1.

Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States.

It is now well established that conical intersections play an essential role in nonadiabatic radiationless decay where their double-cone topography causes them to act as efficient funnels channeling wave packets from the upper to the lower adiabatic state. Until recently, little attention was paid to the effect of conical intersections on dynamics on the lower state, particularly when the total energy involved is significantly below that of the conical intersection seam. This energetic deficiency is routinely used as a sufficient condition to exclude consideration of excited states in ground state dynamics. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00571DOI Listing
February 2019

Intermolecular Acyl-Transfer Reactions in Molecular Crystals.

Acc Chem Res 2019 Feb 30;52(2):437-446. Epub 2019 Jan 30.

Division of Organic Chemistry and the Academy of Scientific and Industrial Research , CSIR-National Chemical Laboratory , Pune 411008 , India.

It is far more difficult to recognize and predict the chemical reactions that a molecule of an organic compound can undergo in crystalline (solid) state as compared to the solution state (the "organic functional group" approach), since the published data on solid-state structure-reactivity investigations and correlations are scant. The discovery of the first intermolecular acyl-transfer reaction in molecular crystals of racemic 2,4-di- O-benzoyl- myo-inositol-1,3,5-orthoformate (DiBz) during our attempts to develop methods for the synthesis of phosphoinositols, motivated us to find other molecular crystals capable of supporting similar reactions. Small changes to the molecular structure of DiBz yielded analogues with different crystal structures which showed varying degrees of acyl transfer reactivity as compared to the crystals of DiBz. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00557DOI Listing
February 2019

Design and Construction of Functional Supramolecular Metalloprotein Assemblies.

Acc Chem Res 2019 Feb 30;52(2):345-355. Epub 2019 Jan 30.

Department of Chemistry and Biochemistry , University of California, San Diego , La Jolla , California 92093-0356 , United States.

Nature puts to use only a small fraction of metal ions in the periodic table. Yet, when incorporated into protein scaffolds, this limited set of metal ions carry out innumerable cellular functions and execute essential biochemical transformations such as photochemical HO oxidation, O or CO reduction, and N fixation, highlighting the outsized importance of metalloproteins in biology. Not surprisingly, elucidating the intricate interplay between metal ions and protein structures has been the focus of extensive structural and mechanistic scrutiny over the last several decades. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00617DOI Listing
February 2019

Study of Fiber-Based Wearable Energy Systems.

Authors:
Xiaoming Tao

Acc Chem Res 2019 Feb 30;52(2):307-315. Epub 2019 Jan 30.

Research Centre for Smart Wearable Technology, Institute of Textiles and Clothing , The Hong Kong Polytechnic University , Hong Kong , China.

Fiber-based electronic and photonic devices have the most desired human-friendly features, such as being soft, ubiquitous, flexible, stretchable, light, and permeable, and thus are ideal to be employed as the interface platform between humans, the environment, and machines. Today, these smart wearable devices are normally powered by rechargeable batteries. It is extremely desirable to have an undisrupted power supply for us to go anywhere at any time. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00502DOI Listing
February 2019
4 Reads

Dielectric Elastomer Artificial Muscle: Materials Innovations and Device Explorations.

Acc Chem Res 2019 Feb 30;52(2):316-325. Epub 2019 Jan 30.

Department of Materials Science and Engineering, Henry Samueli School of Engineering and Applied Science , University of California , Los Angeles , California 90095 , United States.

Creating an artificial muscle has been one of the grand challenges of science and engineering. The invention of such a flexible, versatile, and power efficient actuator opens the gate for a new generation of lightweight, highly efficient, and multifunctional robotics. Many current artificial muscle technologies enable low-power mobile actuators, robots that mimic efficient and natural forms of motion, autonomous robots and sensors, and lightweight wearable technologies. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00516DOI Listing
February 2019

Noble-Metal Substitution in Hemoproteins: An Emerging Strategy for Abiological Catalysis.

Acc Chem Res 2019 Feb 29;52(2):326-335. Epub 2019 Jan 29.

Division of Chemical Sciences, Lawrence Berkeley National Laboratory, and Department of Chemistry , University of California , Berkeley , California 94720 , United States.

Enzymes have evolved to catalyze a range of biochemical transformations with high efficiencies and unparalleled selectivities, including stereoselectivities, regioselectivities, chemoselectivities, and substrate selectivities, while typically operating under mild aqueous conditions. These properties have motivated extensive research to identify or create enzymes with reactivity that complements or even surpasses the reactivity of small-molecule catalysts for chemical reactions. One of the limitations preventing the wider use of enzymes in chemical synthesis, however, is the narrow range of bond constructions catalyzed by native enzymes. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00586DOI Listing
February 2019

Environmental Mercury Chemistry - In Silico.

Acc Chem Res 2019 Feb 28;52(2):379-388. Epub 2019 Jan 28.

Department of Chemistry , University of Manitoba , Winnipeg , MB Canada , R3T 2N2.

Mercury (Hg) is a global environmental contaminant. Major anthropogenic sources of Hg emission include gold mining and the burning of fossil fuels. Once deposited in aquatic environments, Hg can undergo redox reactions, form complexes with ligands, and adsorb onto particles. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00454
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http://dx.doi.org/10.1021/acs.accounts.8b00454DOI Listing
February 2019
7 Reads

Synthesis of Functional Polyacetylenes via Cyclopolymerization of Diyne Monomers with Grubbs-type Catalysts.

Acc Chem Res 2019 Jan 28. Epub 2019 Jan 28.

Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea.

Metathesis cyclopolymerization (CP) of α,ω-diynes is a powerful method to prepare functional polyacetylenes (PAs). PAs have long been studied due to their interesting electrical, optical, photonic, and magnetic properties which make them candidates for use in various advanced applications. Grubbs catalysts are widely used throughout synthetic chemistry, largely due to their accessibility, high reactivity, and tolerance to air, moisture, and many functional groups. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00594DOI Listing
January 2019

Directed Evolution of Artificial Metalloenzymes: A Universal Means to Tune the Selectivity of Transition Metal Catalysts?

Authors:
Manfred T Reetz

Acc Chem Res 2019 Feb 28;52(2):336-344. Epub 2019 Jan 28.

Chemistry Department , Philipps-University , Hans-Meerwein-Strasse 4 , 35032 Marburg , Germany.

Transition metal catalysts mediate a wide variety of chemo-, stereo-, and regioselective transformations, and therefore play a pivotal role in modern synthetic organic chemistry. Steric and electronic effects of ligands provide organic chemists with an exceedingly useful tool. More than four decades ago, chemists began to think about a different approach, namely, embedding achiral ligand/metal moieties covalently or noncovalently in protein hosts with formation of artificial metalloenzymes. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00582DOI Listing
February 2019

Achievements and Challenges for Real-Time Sensing of Analytes in Sweat within Wearable Platforms.

Acc Chem Res 2019 Feb 28;52(2):297-306. Epub 2019 Jan 28.

711th Human Performance Wing , Air Force Research Laboratory , Wright-Patterson AFB , Ohio 45433 , United States.

Physiological sensors in a wearable form have rapidly emerged on the market due to technological breakthroughs and have become nearly ubiquitous with the Apple Watch, FitBit, and other wearable devices. While these wearables mostly monitor simple biometric signatures, new devices that can report on the human readiness level through sensing molecular biomarkers are critical to optimizing the human factor in both commercial sectors and the Department of Defense. The military is particularly interested in real-time, wearable, minimally invasive monitoring of fatigue and human performance to improve the readiness and performance of the war fighter. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00555
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http://dx.doi.org/10.1021/acs.accounts.8b00555DOI Listing
February 2019
9 Reads
22.323 Impact Factor

Allosteric Methods and Their Applications: Facilitating the Discovery of Allosteric Drugs and the Investigation of Allosteric Mechanisms.

Acc Chem Res 2019 Feb 28;52(2):492-500. Epub 2019 Jan 28.

Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education , Shanghai Jiao Tong University, School of Medicine , Shanghai 200025 , China.

Allostery, or allosteric regulation, is the phenomenon in which protein functional activity is altered by the binding of an effector at an allosteric site that is topographically distinct from the orthosteric, active site. As one of the most direct and efficient ways to regulate protein function, allostery has played a fundamental role in innumerable biological processes of all living organisms, including enzyme catalysis, signal transduction, cell metabolism, and gene transcription. It is thus considered as "the second secret of life". Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00570DOI Listing
February 2019
1 Read
22.323 Impact Factor

The Journey of Schinortriterpenoid Total Syntheses.

Authors:
Zhen Yang

Acc Chem Res 2019 Feb 25;52(2):480-491. Epub 2019 Jan 25.

Beijing National Laboratory for Molecular Science and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of the Ministry of Education, College of Chemistry and Molecular Engineering and Peking-Tsinghua Center for Life Sciences , Peking University , Beijing 100871 , China.

Plants in the Schisandraceae family are important components of the traditional Chinese herbal medicines and are often used to treat various illnesses. Therefore, these Schisandraceae plants are valuable sources for the discovery of new chemical entities for novel therapeutic development. Considerable progress has been made in the identification of bioactive and structurally novel triterpenoids from the Schisandraceae family in the past two decades. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00569DOI Listing
February 2019

Growing Prospects of Dynamic Covalent Chemistry in Delivery Applications.

Acc Chem Res 2019 Feb 24;52(2):510-519. Epub 2019 Jan 24.

IBMM, Université de Montpellier, CNRS, ENSCM, Montpellier , France.

Delivery remains a major obstacle restricting the potential action of small molecular drugs as well as novel biologics which cannot readily enter cells without the help of a vector. A successful active delivery process involves three steps: (a) tagging the drug with a vector, (b) effective trafficking of this [drug-vector] conjugate through biological barriers, and finally (c) controlled drug release. While covalent bond formation and/or supramolecular association is involved in the making of the [drug-vector] conjugate, the final step requires precisely a controlled dissociation in order to trigger drug release. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00591DOI Listing
February 2019

Anisotropic Vapor-Deposited Glasses: Hybrid Organic Solids.

Acc Chem Res 2019 Feb 23;52(2):407-414. Epub 2019 Jan 23.

Department of Chemistry , University of Wisconsin-Madison , 1101 University Avenue , Madison , Wisconsin 53706 , United States.

The term "organic solids" encompasses both crystals and glasses. Organic crystals are commonly grown for purification and structure determination and are being extensively explored for applications in organic electronics including field effect transistors. The ability to control the packing of one molecule relative to its neighbors is of critical importance for most uses of organic crystals. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00513DOI Listing
February 2019
2 Reads

Solution-Processed Anatase Titania Nanowires: From Hyperbranched Design to Optoelectronic Applications.

Acc Chem Res 2019 Jan 22. Epub 2019 Jan 22.

MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, Lehn Institute of Functional Materials, School of Chemistry , Sun Yat-sen University , Guangzhou 510275 , P. R. China.

The utilization of solar energy and the development of its related optoelectronic devices have become more important than ever. Solar cells or photoelectrochemical (PEC) cells that require the design of light harvesting assemblies for efficiently converting solar light into electricity or solar fuels are of particular interest. Semiconductor TiO, serving as the photoelectrode for photovoltaic devices (e. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00476DOI Listing
January 2019

Cyclophanes as Platforms for Reactive Multimetallic Complexes.

Acc Chem Res 2019 Feb 22;52(2):447-455. Epub 2019 Jan 22.

Center for Catalysis and Florida Center for Heterocyclic Chemistry, Department of Chemistry , University of Florida , Gainesville , Florida 32611 , United States.

Multimetallic cofactors supported by weak-field donors frequently function as reaction centers in metalloproteins, and many of these cofactors catalyze small molecule activation (e.g., N, O, CO) with prominent roles in geochemical element cycles or detoxification. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00559DOI Listing
February 2019
1 Read

Intensity Fluctuations in Single-Molecule Surface-Enhanced Raman Scattering.

Acc Chem Res 2019 Feb 22;52(2):456-464. Epub 2019 Jan 22.

Department of Chemistry , University of Victoria , P.O. Box 3065, Victoria V8W 3 V6 , BC Canada.

Around 20 years ago, the first reports of single-molecule surface-enhanced Raman scattering (SM-SERS) caused a revolution in nanotechnology. Several researchers were quick to recognize the importance of a technique that can provide molecular vibrational fingerprinting at the SM level. Since then, a large amount of work has been devoted to the development of nanostructures capable of SM-SERS detection. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00563DOI Listing
February 2019
4 Reads

Detection and Application of 5-Formylcytosine and 5-Formyluracil in DNA.

Acc Chem Res 2019 Jan 22. Epub 2019 Jan 22.

College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology , Wuhan University , Wuhan , Hubei 430072 , P. R. China.

Nucleic acids contain a variety of different base modifications, such as decoration at the fifth position of cytosine, which is one of the most important epigenetic modifications. Nucleic acid epigenetics mediate a wide variety of biological processes, including embryonic development and gene regulation, genomic imprinting, differentiation, and X-chromosome inactivation. Furthermore, the modification level can be aberrantly expressed in distinct sets of tissue that can indicate different tumor onsets and canceration. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00543DOI Listing
January 2019
3 Reads

Materials, Structures, and Functions for Flexible and Stretchable Biomimetic Sensors.

Acc Chem Res 2019 Feb 17;52(2):288-296. Epub 2019 Jan 17.

i-Lab and Key Laboratory of Multifunctional Nanomaterials and Smart Systems , Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences (CAS) , 398 Ruoshui Road , Suzhou 215123 , P. R. China.

Currently, flexible and stretchable biomimetic sensing electronics have obtained a great deal of attention in various areas, such as human-machine interfaces, robotic smart skins, health care monitoring, and biointegrated devices. In contrast with the traditional rigid and fragile silicon-based electronics, flexible and stretchable sensing electronics can efficiently capture high-quality signals when integrated on curved surfaces due to their elastic and conformal characters, which are expected to play many important roles in the foreseeable age of intelligence. Its realization strongly relies on rapid advances in the development of high-performance and versatile flexible and stretchable sensors, and effective ways to achieve high performance are rational designs of the sensing materials and microstructural configurations. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00497DOI Listing
February 2019
5 Reads

Bispyrene-Based Self-Assembled Nanomaterials: In Vivo Self-Assembly, Transformation, and Biomedical Effects.

Acc Chem Res 2019 Feb 17;52(2):367-378. Epub 2019 Jan 17.

CAS Center for Excellence in Nanoscience, CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety , National Center for Nanoscience and Technology (NCNST) , No. 11 Beiyitiao, Zhongguancun, Haidian District , Beijing 100190 , China.

Self-assembled nanomaterials show potential high efficiency as theranostic agents for high-performance imaging and therapy. However, superstructures and properties of preassembled nanomaterials are somewhat compromised under complicated physiological conditions. Given the advantages of the dynamic nature and adaptive behavior of self-assembly systems, we propose an "in vivo self-assembly" strategy for in situ construction of nanomaterials in living objects. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00398
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http://dx.doi.org/10.1021/acs.accounts.8b00398DOI Listing
February 2019
12 Reads

NHC-Catalyzed Generation of α,β-Unsaturated Acylazoliums for the Enantioselective Synthesis of Heterocycles and Carbocycles.

Acc Chem Res 2019 Feb 17;52(2):425-436. Epub 2019 Jan 17.

Department of Organic Chemistry , Indian Institute of Science , Bangalore 560012 , India.

This Account is aimed at highlighting the recent developments in the N-heterocyclic carbene (NHC)-catalyzed generation of α,β-unsaturated acylazolium intermediates and their subsequent reactivity with (bis)nucleophiles thereby shedding light on the power of this NHC-bound intermediate in organocatalysis. This key intermediate can be generated by the addition of NHCs to α,β-unsaturated aldehyde or acid derivatives. A wide variety of bisnucleophiles can add across the α,β-unsaturated acylazoliums to form various five and six-membered heterocycles and carbocycles. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00550DOI Listing
February 2019
1 Read

Allenes and Derivatives in Gold(I)- and Platinum(II)-Catalyzed Formal Cycloadditions.

Acc Chem Res 2019 Feb 14;52(2):465-479. Epub 2019 Jan 14.

Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica , Universidad de Santiago de Compostela , 15782 Santiago de Compostela , Spain.

Cycloaddition reactions, by involving the formation of at least two bonds and one cycle in a single operation, represent one of the more practical ways to assemble carbo- and heterocyclic structures from simple acyclic precursors. Especially appealing are formal cycloadditions promoted by transition metals, owing to the ability of these reagents to open mechanisms that are not accessible using classical chemistry. Therefore, along the years, a great variety of annulations based on first-, and particularly second-row transition metals have been discovered. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00567DOI Listing
February 2019
1 Read

Cytochrome P450-The Wonderful Nanomachine Revealed through Dynamic Simulations of the Catalytic Cycle.

Acc Chem Res 2019 Feb 11;52(2):389-399. Epub 2019 Jan 11.

Institute of Chemistry , The Hebrew University of Jerusalem , Givat Ram Campus , 91904 Jerusalem , Israel.

This Account addresses the catalytic cycle of the enzyme cytochrome P450 (CYP450) as a prototypical biological machine with automatic features. CYP450 is a nanomachine that uses dioxygen and two reducing and two proton equivalents to oxidize a plethora of molecules (so-called substrates) as a means of supplying bio-organisms with essential molecules (e.g. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00467
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http://dx.doi.org/10.1021/acs.accounts.8b00467DOI Listing
February 2019
6 Reads

Functionalized Organic Thin Film Transistors for Biosensing.

Acc Chem Res 2019 Feb 8;52(2):277-287. Epub 2019 Jan 8.

Department of Applied Physics , The Hong Kong Polytechnic University , Hong Kong.

The rise of organic bioelectronics efficiently bridges the gap between semiconductor devices and biological systems, leading to flexible, lightweight, and low-cost organic bioelectronic devices suitable for health or body signal monitoring. The introduction of organic semiconductors in the devices can soften the boundaries between microelectronic systems and dynamically active cells and tissues. Therefore, organic bioelectronics has attracted much attention recently due to the unique properties and promising applications. Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00448
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http://dx.doi.org/10.1021/acs.accounts.8b00448DOI Listing
February 2019
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Electrochemical Age Determinations of Metallic Specimens-Utilization of the Corrosion Clock.

Acc Chem Res 2019 Feb 7;52(2):400-406. Epub 2019 Jan 7.

Institut für Biochemie , Universität Greifswald , Felix-Hausdorff Straße 4 , 17487 Greifswald , Germany.

Dating needs an age-dependent phenomenon (a "clock"), a procedure for monitoring the advance of time by measuring a physicochemical quantity, and, in the case of archeological artifacts, a sampling procedure that guarantees the representativity and integrity of the dated objects. Metal corrosion in an aerobic atmosphere is a phenomenon whose advance can in principle be used as a clock that depends on the environmental conditions. In spite of the limitation imposed by differences in local conditions of corrosion, a new approach for age determinations has been developed and applied as a feasible tool for age determinations of metallic specimens studied by archeologists and historians. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00472DOI Listing
February 2019
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Nanoscale Probing of Informational Polymers with Nanopores. Applications to Amyloidogenic Fragments, Peptides, and DNA-PNA Hybrids.

Acc Chem Res 2019 Jan 3. Epub 2019 Jan 3.

Department of Physics , 'Alexandru I. Cuza' University , Iasi , Romania 700506.

The decades long advances in nanotechnology, biomolecular sciences, and protein engineering ushered the introduction of groundbreaking technologies devoted to understanding how matter behaves at single particle level. Arguably, one of the simplest in concept is the nanopore-based paradigm, with deep roots in what is originally known as the Coulter counter, resistive-pulse technique. Historically, a nanopore system comprising the oligomeric protein generated by Staphylococcus aureus toxin α-hemolysin (α-HL) was first applied to detecting polynucleotides, as revealed in 1996 by John J. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00565DOI Listing
January 2019
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Chiral-Icosahedral ( I) Symmetry in Ubiquitous Metallic Cluster Compounds (145A,60X): Structure and Bonding Principles.

Acc Chem Res 2019 Jan 2. Epub 2019 Jan 2.

Instituto de Física , Universidad Nacional Autónoma de México , Apartado Postal 20-364, 01000 CDMX , México.

There exists a special kind of perfection-in symmetry, simplicity, and stability-attainable for structures generated from precisely 60 ligands (all of a single type) that protect 145 metal-atom sites. The symmetry in question is icosahedral ( I), generally, and chiral icosahedral ( I) in particular. A 60-fold equivalence of the ligands is the smallest number to allow this kind of perfection. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00481DOI Listing
January 2019
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Systems Approaches for Unveiling the Mechanism of Action of Bismuth Drugs: New Medicinal Applications beyond Helicobacter Pylori Infection.

Acc Chem Res 2018 Dec 31. Epub 2018 Dec 31.

Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong , China.

Metallodrugs have been widely used as diagnostic and therapeutic agents. Understanding their mechanisms of action may lead to advances in rational drug design. However, to achieve this, diversified approaches are required because of the complexity of metal-biomolecule interactions. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00439DOI Listing
December 2018
3 Reads

Predissociation Measurements of Bond Dissociation Energies.

Authors:
Michael D Morse

Acc Chem Res 2018 Dec 31. Epub 2018 Dec 31.

Department of Chemistry , University of Utah , 315 South 1400 East , Salt Lake City , Utah 84112 , United States.

A fundamental need in chemistry is understanding the chemical bond, for which the most quantitative measure is the bond dissociation energy (BDE). While BDEs of chemical bonds formed from the lighter main group elements are generally well-known and readily calculated by modern computational chemistry, chemical bonds involving the transition metals, lanthanides, and actinides remain computationally extremely challenging. This is due to the simultaneous importance of electron correlation, spin-orbit interaction, and other relativistic effects, coupled with the large numbers of low-lying states that are accessible in systems with open d or f subshells. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00526DOI Listing
December 2018
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Understanding Charge Transport in Carbon Nitride for Enhanced Photocatalytic Solar Fuel Production.

Acc Chem Res 2018 Dec 31. Epub 2018 Dec 31.

McKetta Department of Chemical Engineering and Department of Chemistry, Texas Materials Institute and Center for Electrochemistry , The University of Texas at Austin , Austin , Texas 78712-1589 , United States.

Photocatalytic solar fuel production, for example, production of hydrogen via water-splitting, is an effective means of chemical storage of solar energy and provides a potential option for achieving a zero-emissions energy system. Conveniently, hydrogen can be converted back to electricity either via fuel cells or through combustion in gas turbines, or it can be mixed in low concentrations with natural gas or biogas for combustion in existing power plants. The cornerstone of a practical solar fuel production process is a stable, efficient, and scalable photocatalyst (a semiconductor material that accommodates photon absorption, charge carrier generation and transport, and catalytic reactions). Read More

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http://pubs.acs.org/doi/10.1021/acs.accounts.8b00542
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http://dx.doi.org/10.1021/acs.accounts.8b00542DOI Listing
December 2018
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Development and Evolution of Mechanistic Understanding in Iron-Catalyzed Cross-Coupling.

Acc Chem Res 2018 Dec 28. Epub 2018 Dec 28.

Department of Chemistry , University of Rochester , Rochester , New York 14627 , United States.

Since the pioneering work of Kochi in the 1970s, iron has attracted great interest for cross-coupling catalysis due to its low cost and toxicity as well as its potential for novel reactivity compared to analogous reactions with precious metals like palladium. Today there are numerous iron-based cross-coupling methodologies available, including challenging alkyl-alkyl and enantioselective methods. Furthermore, cross-couplings with simple ferric salts and additives like NMP and TMEDA ( N-methylpyrrolidone and tetramethylethylenediamine) continue to attract interest in pharmaceutical applications. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00519DOI Listing
December 2018
3 Reads

Wearable and Implantable Soft Bioelectronics Using Two-Dimensional Materials.

Acc Chem Res 2018 Dec 26. Epub 2018 Dec 26.

Center for Nanoparticle Research , Institute for Basic Science (IBS) , Seoul 08826 , Republic of Korea.

Soft bioelectronics intended for application to wearable and implantable biomedical devices have attracted great attention from material scientists, device engineers, and clinicians because of their extremely soft mechanical properties that match with a variety of human organs and tissues, including the brain, heart, skin, eye, muscles, and neurons, as well as their wide diversity in device designs and biomedical functions that can be finely tuned for each specific case of applications. These unique features of the soft bioelectronics have allowed minimal mechanical and biological damage to organs and tissues integrated with bioelectronic devices and reduced side effects including inflammation, skin irritation, and immune responses even after long-term biointegration. These favorable properties for biointegration have enabled long-term monitoring of key biomedical indicators with high signal-to-noise ratio, reliable diagnosis of the patient's health status, and in situ feedback therapy with high treatment efficacy optimized for the requirements of each specific disease model. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00491DOI Listing
December 2018
2 Reads

Block Copolymer Elastomers for Stretchable Electronics.

Acc Chem Res 2018 Dec 26. Epub 2018 Dec 26.

Department of Materials Science and Engineering , Pohang University of Science and Technology (POSTECH) , 77 Cheongam-Ro , Nam-Gu, Pohang 37673 , Republic of Korea.

As industrial needs for healthcare sensors, electronic skin, and flexible/stretchable displays increase, interest in stretchable materials is increasing as well. In recent years, the studies on stretchable materials have spread to various pivot components, such as electrodes, circuits, substrates, semiconductors, dielectric layers, membranes, and active nanocomposite films. The block copolymer (BC) elastomers have been playing considerable role in the development of stretchable materials. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00488DOI Listing
December 2018
3 Reads

Understanding and Quantifying London Dispersion Effects in Organometallic Complexes.

Acc Chem Res 2018 Dec 26. Epub 2018 Dec 26.

Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry , University of Bonn , Beringstr. 4 , 53115 Bonn , Germany.

Quantum chemical methods are nowadays able to determine properties of larger chemical systems with high accuracy and Kohn-Sham density functional theory (DFT) in particular has proven to be robust and suitable for everyday applications of electronic structure theory. A clear disadvantage of many established standard density functional approximations like B3LYP is their inability to describe long-range electron correlation effects. The inclusion of such effects, also termed London dispersion, into DFT has been extensively researched in recent years, resulting in some efficient and routinely used correction schemes. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00505DOI Listing
December 2018
8 Reads

Stretchable, Skin-Attachable Electronics with Integrated Energy Storage Devices for Biosignal Monitoring.

Acc Chem Res 2018 Dec 26. Epub 2018 Dec 26.

Department of Chemical and Biological Engineering , Korea University , 145, Anam-ro , Seongbuk-gu, Seoul 02841 , Republic of Korea.

The demand for novel electronics that can monitor human health, for example, the physical conditions of individuals, during daily life using different techniques from those used in traditional clinic diagnostic facilities is increasing. These novel electronics include stretchable sensor devices that allow various biosignals to be directly measured on human skin without restricting routine activity. The thin, skin-like characteristics of these devices enable stable operation under various deformations, such as stretching, pressing, and rubbing, experienced while attached to skin. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00508DOI Listing
December 2018
1 Read

Integrating Combinatorial Lipid Nanoparticle and Chemically Modified Protein for Intracellular Delivery and Genome Editing.

Acc Chem Res 2018 Dec 26. Epub 2018 Dec 26.

Department of Biomedical Engineering , Tufts University , Medford , Massachusetts 02155 , United States.

The use of protein to precisely manipulate cell signaling is an effective approach for controlling cell fate and developing precision medicine. More recently, programmable nucleases, such as CRISPR/Cas9, have shown extremely high potency for editing genetic flow of mammalian cells, and for treating genetic disorders. The therapeutic potential of proteins with an intracellular target, however, is mostly challenged by their low cell impermeability. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00493DOI Listing
December 2018
1 Read
22.323 Impact Factor

Heterogeneous Strain Distribution of Elastomer Substrates To Enhance the Sensitivity of Stretchable Strain Sensors.

Acc Chem Res 2018 Dec 26. Epub 2018 Dec 26.

Innovative Centre for Flexible Devices (iFLEX), School of Materials Science and Engineering , Nanyang Technological University , 50 Nanyang Avenue , Singapore 639798 , Singapore.

Stretchable strain sensors, which convert mechanical stimuli into electrical signals, largely fuel the growth of wearable bioelectronics due to the ubiquitous, health-related strain in biological systems. In contrast to rigid conventional strain sensors, stretchable strain sensors present advantages of conformality and stretchability, solving the mechanical mismatch between electronics and the human body. However, the great challenge of stretchable strain sensors lies in achieving high sensitivity, which is required for both signal fidelity and cost considerations. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00499DOI Listing
December 2018
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Photochemical Properties of Host-Guest Supramolecular Systems with Structurally Confined Metal-Organic Capsules.

Acc Chem Res 2018 Dec 26. Epub 2018 Dec 26.

State Key Laboratory of Fine Chemicals, Zhang Dayu College of Chemistry , Dalian University of Technology , Dalian , 116024 , P. R. China.

Inspired by natural photosynthesis, researchers have designed symmetric metal-organic hosts with large inner pockets that are spontaneously generated through preorganized ligands and functionalized metallocorners to construct dye-containing host-guest systems. The abundant noncovalent interaction sites in the pockets of the hosts facilitated substrate-catalyst interactions for possible enrichment, fixation, and activation of substrates/reagents, providing special electron transfer pathways for regio- or stereoselectively photocatalytic chemical transformations. In this Account, we focus our attention on metal-organic hosts that contain photoactive or redox-active units to evaluate electron transfer and charge separation between host and guest units in these supramolecular systems and elucidate the related photoinduced chemical reactions controlled by these electron transfer processes within the structurally confined pockets of these interesting metal-organic hosts. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00463DOI Listing
December 2018
1 Read
22.323 Impact Factor

Total Synthesis in Search of Potent Antibody-Drug Conjugate Payloads. From the Fundamentals to the Translational.

Acc Chem Res 2018 Dec 21. Epub 2018 Dec 21.

Department of Chemistry, BioScience Research Collaborative , Rice University , 6100 Main Street , Houston , Texas 77005 , United States.

The emergence and evolution of antibody-drug conjugates (ADCs) as targeted cancer therapies in recent years is a living example of the "magic bullet" concept of Paul Ehrlich, introduced by him more than a century ago. Consisting of three components, the antibody serving as the delivery system, the payload drug that kills the cancer cell, and the chemical linker through which the payload is attached to the antibody, ADCs represent a currently hotly pursued paradigm of targeted cancer therapies. While the needed monoclonal antibody falls in the domains of biology and biochemistry, the potent payload and the linker belong to the realm of chemistry. Read More

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http://dx.doi.org/10.1021/acs.accounts.8b00537DOI Listing
December 2018
1 Read