Advances In Molecular Design Research Articles

Recent progress in thermally activated delayed fluorescence dendrimers for solution‐processed organic light‐emitting diodes

AbstractDuring the past decade, the discovery of thermally activated delayed fluorescence (TADF) materials has significantly boosted the development of organic light‐emitting diode (OLED) technology. Compared with small‐molecule and polymeric TADF materials, TADF dendrimers have emerged as promising emitters for solution‐processed OLEDs because they have the integrated advantages of TADF small molecules and polymers in achieving high efficiency, excellent solution processability, and precise molecular structures. In recent years, TADF dendrimers have experienced important advances in molecular design, mechanism exploration and device performance. Herein, we present a comprehensive review of solution‐processable TADF dendrimers, mainly focusing on their molecular design principles and structure–property correlations. The advanced device performances of these dendrimers are also summarized. Finally, we proposed the prospects and challenges on the development of TADF dendrimers.

Advances in Molecular Design and Photophysical Engineering of Perylene Bisimide-Containing Polyads and Multichromophores for Film-Based Fluorescent Sensors.

Film-based fluorescent sensors (FFSs) represent an important chemistry technology for meeting the urgent needs of on-site and real-time analysis, thereby enabling significant applications in environmental and health monitoring. As the core of FFSs, innovative design of sensing fluorophores and their intrinsic excited-state-related response nature endow FFSs with superior sensing performances in an endless expansion. In this Perspective, we specifically focus on perylene bisimide (PBI)-containing polyads and multichromophores with rigid configuration and notable photochemical stability for developing high-performance FFSs. These nonplanar structures mitigate aggregation and create abundant gaps for the sake of mass transfer and availability of the sensing units in the adlayer of the sensing films. We also comprehensively discuss how to adjust electronic coupling governing the excited-state events by appropriate functionalization strategies, thus providing a plethora of valuable insights for the exploration of the structure-property relationships in these orchestrated molecular systems. Throughout this Perspective, we also identify opportunities for FFSs in the future developments.

In Vivo Electrochemical Biosensors: Recent Advances in Molecular Design, Electrode Materials, and Electrochemical Devices.

Electrochemical biosensors provide powerful tools for dissecting the dynamically changing neurochemical signals in the living brain, which contribute to the insight into the physiological and pathological processes of the brain, due to their high spatial and temporal resolutions. Recent advances in the integration of in vivo electrochemical sensors with cross-disciplinary advances have reinvigorated the development of in vivo sensors with even better performance. In this Review, we summarize the recent advances in molecular design, electrode materials, and electrochemical devices for in vivo electrochemical sensors from molecular to macroscopic dimensions, highlighting the methods to obtain high performance for fulfilling the requirements for determination in the complex brain through flexible and smart design of molecules, materials, and devices. Also, we look forward to the development of next-generation in vivo electrochemical biosensors.

MRNA therapeutics for disease therapy: principles, delivery, and clinical translation.

Messenger RNA (mRNA) has become a key focus in the development of therapeutic agents, showing significant potential in preventing and treating a wide range of diseases. The COVID-19 pandemic in 2020 has accelerated the development of mRNA nucleic therapeutics and attracted significant investment from global biopharmaceutical companies. These therapeutics deliver genetic information into cells without altering the host genome, making them a promising treatment option. However, their clinical applications have been limited by issues such as instability, inefficient in vivo delivery, and low translational efficiency. Recent advances in molecular design and nanotechnology have helped overcome these challenges, and several mRNA formulations have demonstrated promising results in both animal and human testing against infectious diseases and cancer. This review provides an overview of the latest research progress in structural optimization strategies and delivery systems, and discusses key considerations for their future clinical use.

Bioinspired Fluorescent Polymers: Synthesis, Processing, and Applications†

Comprehensive SummaryThe discovery of fluorescent proteins has inspired a lot of interest to develop synthetic polymers with similar structures and functionalities. In this review article, we first give a brief introduction for the discovery, the structural characteristics and optical properties of fluorescent proteins, using green fluorescent protein (GFP) as an example. In the body part of article, we summarize recent advances in molecular design, synthesis and processing of bioinspired fluorescent polymers with unique optical properties such as high fluorescence quantum yield and robust photostability. Several major approaches highlighted here include the recombination of organic chromophores and proteins, and synthesis of the bioinspired polymers containing a single fluorophore in each polymer chain. The optical properties and applications of some representative bioinspired fluorescent polymers in bioimaging, sensing and imaging‐guided therapy are also elucidated.

Exploring Axial Organic Multiblock Heterostructure Nanowires: Advances in Molecular Design, Synthesis, and Functional Applications

AbstractOrganic multiblock heterostructure nanowires (OMHNs), integrating distinct components in the same axial structure, have attracted much attention due to their excellent properties such as intrinsic good light confinement and rectification characteristics. However, rationally incorporating such features into OMHNs with rigorous 1D morphology control remains a key synthetic objective. It is because that the single components possess fundamentally distinctive properties such as size‐dependent electronic, optical, and magnetic features as well as lattice parameters. In the last decade, researchers made their own efforts to this exciting field, especially from the controlled fabrication to the advanced applications of the multiblock nanowires. As a result, various OMHNs have been developed as very promising candidates for high‐performance optoelectronic applications such as light harvesting, logic gate devices, photonic transistors, and photonic anticounterfeiting. Herein, the recent advances of OMHNs from the aspects of molecular design, synthesis, and advanced applications are reviewed, and an outlook is given providing inspiration for the future development of OMHNs toward integrated optoelectronic at nanoscale.

Enhancing the Performance of Small-Molecule Organic Solar Cells via Fused-Ring Design.

Organic solar cells (OSCs) as the promising green energy technology have drawn much attention in the last two decades. In comparison to polymer solar cells, small-molecule organic solar cells (SMOSCs) have the advantages of precise chemical structure and molecular weight, purification feasibility, batch reproducibility, etc. Despite of the recent advances in molecular design, the efficiencies of SMOSCs are still lagging behind those of polymer-based OSCs. In this work, a new small-molecule donor (SMD) with a fused-ring-connected bridge denoted F-MD has been designed and synthesized. When F-MD was applied into SMOSCs, the F-MD:N3 blends exhibited a power conversion efficiency (PCE) of over 13%, which is much higher than that of the linear π-bridged molecule L-MD based devices (8.12%). Further studies revealed that the fused-ring design promoted the planarity of the molecular conformation and facilitated charge transport in OSCs. More importantly, this strategy also lowered the crystallinity and self-aggregation of the films, and hence optimized the microstructure and phase separation in the corresponding blends. Thereby, the F-MD-based blends have been evidenced to have better exciton dissociation and reduced charge recombination in comparison with the L-MD counterparts, explaining the enhanced PCEs. Our work demonstrates that the fused-ring π-bridge strategy in small-molecule-donor design is an effective pathway to promote the efficiency of SMOSCs as well as enhance the diversity of SMD materials.

Recent advances of NIR-TADF (λmaxPL/EL > 700 nm) emitters and their applications in OLEDs

This review presents a new vista on the recent advances in molecular design, photophysical and electroluminescence performances of NIR emitters and their OLEDs.

Integrating Emerging Polymer Chemistries for the Advancement of Recyclable, Biodegradable, and Biocompatible Electronics.

Through advances in molecular design, understanding of processing parameters, and development of non‐traditional device fabrication techniques, the field of wearable and implantable skin‐inspired devices is rapidly growing interest in the consumer market. Like previous technological advances, economic growth and efficiency is anticipated, as these devices will enable an augmented level of interaction between humans and the environment. However, the parallel growing electronic waste that is yet to be addressed has already left an adverse impact on the environment and human health. Looking forward, it is imperative to develop both human‐ and environmentally‐friendly electronics, which are contingent on emerging recyclable, biodegradable, and biocompatible polymer technologies. This review provides definitions for recyclable, biodegradable, and biocompatible polymers based on reported literature, an overview of the analytical techniques used to characterize mechanical and chemical property changes, and standard policies for real‐life applications. Then, various strategies in designing the next‐generation of polymers to be recyclable, biodegradable, or biocompatible with enhanced functionalities relative to traditional or commercial polymers are discussed. Finally, electronics that exhibit an element of recyclability, biodegradability, or biocompatibility with new molecular design are highlighted with the anticipation of integrating emerging polymer chemistries into future electronic devices.

Recent Advances in the Molecular Design and Applications of Multispecific Biotherapeutics.

Recombinant protein-based biotherapeutics drugs have transformed clinical pipelines of the biopharmaceutical industry since the launch of recombinant insulin nearly four decades ago. These biologic drugs are structurally more complex than small molecules, and yet share a similar principle for rational drug discovery and development: That is to start with a pre-defined target and follow with the functional modulation with a therapeutic agent. Despite these tremendous successes, this “one target one drug” paradigm has been challenged by complex disease mechanisms that involve multiple pathways and demand new therapeutic routes. A rapidly evolving wave of multispecific biotherapeutics is coming into focus. These new therapeutic drugs are able to engage two or more protein targets via distinct binding interfaces with or without the chemical conjugation to large or small molecules. They possess the potential to not only address disease intricacy but also exploit new therapeutic mechanisms and assess undruggable targets for conventional monospecific biologics. This review focuses on the recent advances in molecular design and applications of major classes of multispecific biotherapeutics drugs, which include immune cells engagers, antibody-drug conjugates, multispecific tetherbodies, biologic matchmakers, and small-scaffold multispecific modalities. Challenges posed by the multispecific biotherapeutics drugs and their future outlooks are also discussed.

TADF Parameters in the Solid State: An Easy Way to Draw Wrong Conclusions

The successful development of thermally activated delayed fluorescence (TADF) OLEDs relies on advances in molecular design. To guide the molecular design toward compounds with preferable properties, special care should be taken while estimating the parameters of prompt and delayed fluorescence. Mistakes made in the initial steps of analysis may lead to completely misleading conclusions. Here we show that inaccuracies usually are introduced in the very first steps while estimating the solid-state prompt and delayed fluorescence quantum yields, resulting in an overestimation of prompt fluorescence (PF) parameters and a subsequent underestimation of the delayed emission (DF) yield and rates. As a solution to the problem, a working example of a more sophisticated analysis is provided, stressing the importance of in-depth research of emission properties in both oxygen-saturated and oxygen-free surroundings.

Peptide Nucleic Acids and Gene Editing: Perspectives on Structure and Repair.

Unusual nucleic acid structures are salient triggers of endogenous repair and can occur in sequence-specific contexts. Peptide nucleic acids (PNAs) rely on these principles to achieve non-enzymatic gene editing. By forming high-affinity heterotriplex structures within the genome, PNAs have been used to correct multiple human disease-relevant mutations with low off-target effects. Advances in molecular design, chemical modification, and delivery have enabled systemic in vivo application of PNAs resulting in detectable editing in preclinical mouse models. In a model of β-thalassemia, treated animals demonstrated clinically relevant protein restoration and disease phenotype amelioration, suggesting a potential for curative therapeutic application of PNAs to monogenic disorders. This review discusses the rationale and advances of PNA technologies and their application to gene editing with an emphasis on structural biochemistry and repair.

Central-to-Helical-to-Axial-to-Central Transfer of Chirality with a Photoresponsive Catalyst.

Recent advances in molecular design have displayed striking examples of dynamic chirality transfer between various elements of chirality, e.g., from central to either helical or axial chirality and vice versa. While considerable progress in atroposelective synthesis has been made, it is intriguing to design chiral molecular switches able to provide selective and dynamic control of axial chirality with an external stimulus to modulate stereochemical functions. Here, we report the synthesis and characterization of a photoresponsive bis(2-phenol)-substituted molecular switch 1. The unique design exhibits a dynamic hybrid central-helical-axial transfer of chirality. The change of preferential axial chirality in the biaryl motif is coupled to the reversible switching of helicity of the overcrowded alkene core, dictated by the fixed stereogenic center. The potential for dynamic control of axial chirality was demonstrated by using (R)-1 as switchable catalyst to direct the stereochemical outcome of the catalytic enantioselective addition of diethylzinc to aromatic aldehydes, with successful reversal of enantioselectivity for several substrates.

Biomimetic antimicrobial polymers: recent advances in molecular design

The increasing prevalence of antibiotic-resistant bacterial infections, coupled with the decline in the number of new antibiotic drug approvals, has created a therapeutic gap that portends an emergent public health crisis.

Alternative Affinity Ligands for Immunoglobulins.

The demand for recombinant therapeutic antibodies and Fc-fusion proteins is expected to increase in the years to come. Hence, extensive efforts are concentrated on improving the downstream processing. In particular, the development of better-affinity chromatography matrices, supporting robust time- and cost-effective antibody purification, is warranted. With the advances in molecular design and high-throughput screening approaches from chemical and biological combinatorial libraries, novel affinity ligands representing alternatives to bacterial immunoglobulin (Ig)-binding proteins have entered the scene. Here, we review the design, development, and properties of diverse classes of alternative antibody-binding ligands, ranging from engineered versions of Ig-binding proteins, to artificial binding proteins, peptides, aptamers, and synthetic small-molecular-weight compounds. We also provide examples of applications for the novel affinity matrices in chromatography and beyond.

Engineering radical polymer electrodes for electrochemical energy storage

Abstract In principle a wide range of organic materials can store energy in the form of reversible redox conversions of stable radicals. Such chemistry holds great promise for energy storage applications due to high theoretical capacities, high rate capabilities, intrinsic structural tunability, and the possibility of low-cost “green” syntheses from renewable sources. There have been steady improvements in the design of organic radical polymers, in which radicals are incorporated into the backbone and/or as pendant groups. This review highlights opportunities for improved redox molecule and polymer design along with the key challenges (e.g., transport phenomena, solubility, and reaction mechanisms) to transitioning known organic radicals into high-performance electrodes. Ultimately, organic-based batteries are still a nascent field with many open questions. Further advances in molecular design, electrode engineering, and device architecture will be required for these systems to reach their full potential and meet the diverse and increasing demands for energy storage.

Advances in molecular design of biopolymer-based delivery micro/nanovehicles for essential fatty acids

The demand of food products fortified with essential omega-3 polyunsaturated fatty acids (PUFAs) continues to increase around the world. However, the increased oxidative instability of omega-3 PUFAs hinders their use as health-promoting food ingredients owing to the expected deterioration of the food product quality. One of the successful ways to tackle this difficulty is the micro- and nanoencapsulation of PUFAs in the different kinds of the biopolymer-based delivery systems. By this means this review article focuses on the recent advances in the molecular design of biopolymer – based nanoscale delivery systems (nanoparticles and nanoelmulsions) for essential PUFAs specifically. These advances concern the ways of both the formation of such systems and the biopolymer modification (physical, chemical or enzymatic), which are used to increase the potential of biopolymers relative to the PUFAs nanoencapsulation and protection against oxidation in particular.

Molecular engineering of sensitizers for dye‐sensitized solar cell applications

Dye-sensitized solar cells (DSSCs) have attracted considerable attention in recent years as they offer the possibility of low-cost conversion of photovoltaic energy. This account focuses on recent advances in molecular design and technological aspects of sensitizers based on metal complexes, metal-free organics and tetrapyrrolic compounds which include porphyrins, phthalocyanines as well as corroles. Special attention has been paid to the design principles of these dyes, and co-sensitization, an emerging technique to extend the absorption range, is also discussed as a way to improve the performance of the device. This account also focuses on recent advances of efficient ruthenium sensitizers as well as other metal complexes and their applications in DSSCs. Recent developments in the area of metal-free organic and tetrapyrrolic sensitizers are also discussed.

ChemInform Abstract: Fluorescent DNA‐Based Enzyme Sensors

AbstractReview: 160 refs.

Fluorescent DNA-based enzyme sensors.

Fluorescent sensors that make use of DNA structures have become widely useful in monitoring enzymatic activities. Early studies focused primarily on enzymes that naturally use DNA or RNA as the substrate. However, recent advances in molecular design have enabled the development of nucleic acid sensors for a wider range of functions, including enzymes that do not normally bind DNA or RNA. Nucleic acid sensors present some potential advantages over classical small-molecule sensors, including water solubility and ease of synthesis. An overview of the multiple strategies under recent development is presented in this critical review, and expected future developments in microarrays, single molecule analysis, and in vivo sensing are discussed (160 references).