The spatial heterogeneity of multiple organs causes the complexity of the molecular mechanism in environmental pollutant-exposed organisms. The conventional environmental toxicology research based on chemical and biological analysis has been considered as a “homogeneous” whole, which is difficult to locate the pollutant and its metabolism in spatial level. As one of the most promising analytical method, mass spectrometry imaging(MSI) combined with mass spectrometry-based omics has been applied for the qualitative, quantitative and spatial localization analysis of pollutant and its metabolic activation pathways as well as biomolecule variation, allowing the screening of pollutant exposure-related target organs and investigation of the migration and biological effects of pollutants. Herein, we summarize the strategies and characteristics of MSI and omics in environmental toxicology. The future development and challenges are also prospected, including the single cell imaging, and the integrated microfluidic chip-MSI technique.

Contents

1 Introduction

2 MSI and omics analysis

2.1 Pollutant exposed experimental models

2.2 Pollutant exposed histological analysis

2.3 MSI and omics-based environmental toxicology research

2.4 Exploration of toxicological mechanisms

3 Toxicity research of typical pollutants

3.1 Bisphenols

3.2 PM2.5

3.3 Other applications

4 Conclusion and perspective

Carbonylation(such as hydroformylation, alkoxycarbonylation, hydroxycarbonylation, aminocarbonylation) provides an effective way to synthesize the high value-added carbonyl compounds such as aldehydes(/alcohols), carboxylic acids, carboxylate esters, amides etc., which is advantageous with high atom-economy, excellent selectivities, and mild conditions in comparison to the oxidation. The raw materials involved in carbonylation are comprised of alkenes, alkynes, halohydrocarbons, alcohols etc. Thereinto, with CO or CO-surrogates as carbonyl source, carbonylation of alkyne with different nucleophiles(such as water, alcohols, amines) over transition-metal catalysts, is one of the most attractive processes to produce the corresponding carbonyl compounds like carboxylic acids, carboxylate esters and amines with 100% atom-economy. The obtained carbonyl compounds are widely applied in the production of pharmaceuticals, foods, and cosmetics as well as organic synthesis like polymerization, Aldol condensation and Micheal addition. In this review, the research status on carbonylation of alkynes in recent decade, in terms of reaction types and carbonyl sources, are summarized and prospected.

Contents

1 Introduction

2 Alkoxycarbonylation of alkynes

3 Aminocarbonylation of alkynes

4 Hydroxycarbonylation of alkynes

5 Double carbonylation of alkynes

6 CO surrogates in carbonylation of alkynes

6.1 Formates as CO source

6.2 Formic acid as CO source

6.3 Metal-carbonyl compounds as CO source

7 Conclusion and outlook

Coronavirus(CoV) is a class of enveloped, positive-sense single-stranded RNA viruses which can infect humans and animals. At the end of 2019, a novel β-coronavirus SARS-CoV-2(Severe acute respiratory syndrome-coronavirus-2) has started to spread from person to person, and the virus-related disease "COVID-19"(Coronavirus disease 2019) poses a serious threat to global public health in different countries. Glycosylation is a post-translational modification that exists on proteins, which can affect the protein folding, stability, and the binding between virus and host receptors. Spike(S) protein determines the tropism of the virus to the host. A plenty of studies have shown that the spike(S) protein in the SARS-CoV-2 envelope and the main receptor on the host cell, Angiotensin converting enzyme 2(ACE2), are highly glycosylated proteins. To explore the role of glycosylation in virus infection and host immune response, this review summarizes the infection mechanism of SARS-CoV-2, the glycosylation modifications of recombinant S protein and host receptor protein ACE2, and the effects of glycosylation on the interaction between virus and host cells. Finally, based on the mechanism of glycosylation, we propose novel potential strategies for COVID-19 diagnosis and anti-virus drug development, which provides new directions for the diagnosis and treatment of COVID-19.

Contents

1 Introduction

2 The infection mechanism of SARS-CoV-2

3 S protein: highly glycosylated viral tropic protein

3.1 Viral glycosylation mechanism: host-dependent glycosylation modification system

3.2 Subtypes of glycosylation and the related sites

3.3 The role of viral protein glycosylation

4 Glycosylation modification of host receptor protein ACE2

5 SARS-CoV-2 detection and drug intervention strategies based on glycosylation

5.1 Development of efficient and sensitive kits using agglutination

5.2 Drugs that affects glycosylation

6 Conclusion and outlook

Clinical studies have confirmed that strontium ranelate can inhibit osteoporosis by improving bone formation and reducing bone resorption. These effects are partly mediated by the effect of strontium on bone metabolism. Trace element strontium can promote osteogenesis as well as angiogenesis. To date, the research on strontium-doped composites is increasing in orthopaedic related field. The current article mainly reviews the main action mechanisms of strontium on bone tissue, including the validated and potential mechanisms, as well as the detailed biological interaction between strontium and bone. This article also focuses on different strontium-doped biomaterials applied in the local bone tissue repair, especially for the osteoporotic bone regeneration. We hope that this review would shed light on the rationale for further application of strontium in bone repair.

Contents:

1 Introduction

2 Action mechanism of strontium

2.1 Effect of strontium on osteogenesis

2.2 Effects of strontium on osteoclastogenesis

2.3 Effects of strontium on angiogenesis

3 Strontium doped bone repair materials

3.1 Strontium-doped bone cement

3.2 Strontium-doped calcium phosphate bioceramic

3.3 Strontium-doped bioactive glass

3.4 Bioactive coating of strontium-doped composite

3.5 Other strontium-doped multiphase composites

4 Conclusion and outlook

In order to handle a large number of experiment conditions and outputs and further accelerate the material development process, high-throughput screening has become a more and more important experimental method, which has been widely used in many fields to improve experimental efficiency. And the high-throughput platform is the basic condition for carrying out high-throughput experiments. Existing high-throughput platforms, like microtiter plates, still suffer from problems such as high consumption and low experimental throughput when dealing with precious samples and reagents and further optimization is still required. As an emerging miniaturized and integrated high-throughput platform, droplet microarrays have the advantages of low consumption of reagent and sample, short reaction time, high integration and strong operability, and have been widely studied and applied in the field of biomedicine. In this paper, the construction methods of droplet microarrays are summarized and divided into two categories: surface chemistry driving and physical morphology assisted. The advantages and disadvantages of different construction methods are briefly analyzed. Then the applications of droplet microarrays in biomedical high-throughput research are also briefly introduced from the four directions of 2D cell screening, 3D cell culture, single cell analysis and whole organism screening. Finally, the problems existing in the application process of droplet microarrays and its future development direction are also summarized and analyzed.

Contents

1 Introduction

2 Construction methods

2.1 Surface chemistry

2.2 Surface morphology

3 Applications in biomedical high-throughput research

3.1 2D cell screening

3.2 3D cell culture

3.3 Single cell analysis

3.4 Whole organism screening

4 Conclusion and outlook

Single-cell level detection can distinguish rare abnormal cells from large cell populations, which plays a vital role in biomedical fields such as early diagnosis and treatment evaluation of diseases. By integrating microfluidics, electrical impedance spectroscopy and flow cytometry, the microfluidic impedance cytometer has attracted extensive attention, as it can realize non-destructive impedance detection of single cells in a continuous way with precise flow control. Compared with traditional single-cell detection methods, microfluidic impedance cytometer has significant advantages such as label-free, multi-parameters, low pollution and high throughput, providing a powerful tool for cell population identification and status monitoring. Therefore, various microfluidic impedance cytometers with different structures and functions have been successfully developed in recent years. In this review, we first summarize the working principles and recent developments of DC impedance cytometer, AC impedance cytometer and deformability impedance cytometer, and then focus on the latest applications of microfluidic impedance cytometer in the detection of biological samples such as blood cells, cancer cells and microorganisms. Later, the application prospect of microfluidic impedance cytometer in clinical real-time detection from the aspects of integration and miniaturization are also presented. Finally, the shortcomings of the existing microfluidic impedance cytometers and the future development trend in this field are discussed.

Contents

1 Introduction

2 Microfluidic impedance cytometer

2.1 DC impedance cytometer

2.2 AC impedance cytometer

2.3 Deformability impedance cytometer

3 Applications in single-cell detection

3.1 Blood cells

3.2 Cancer cells

3.3 Bacteria

4 Applications in point-of-care testing

4.1 Chip integration

4.2 Chip miniaturization

5 Conclusion and outlook

As a powerful tool for monitoring brain activities, neural electrodes have been playing a crucial role in the understanding of brain functions and the treatment of neurological disorders. In particular, the construction of a stable electrode-neural interface is critical for the stable chronic neural recording. However, conventional neural electrodes are mainly constructed with rigid materials, whose Young’s moduli are several orders of magnitude higher than that of the brain tissue. This large mechanical mismatch causes the micromotion of the neural electrodes, which elicits inflammatory response of the brain tissue and thus limits the stable chronic neural recording. With the one-atom thickness, graphene has been considered as a promising active material for neural electrodes with stable electrode-neural interfaces for its high conductivity, excellent flexibility and good biocompatibility. In this review, we provide an overview of graphene for neural activity recording, from their modulation on the growth of neurons to applications in bothin vitro and in vivo neural activity recording. At last, challenges and prospects of graphene for neural activity recording are proposed.

Contents

1 Introduction

2 Graphene microelectrodes for cell culture and in vitro neural activity recording

2.1 Graphene for cell growth and modulation

2.2 Graphene microelectrodes for in vitro neural activity recording

3 Graphene microelectrodes for in vivo neural activity recording

3.1 Graphene-based electrocorticography(ECoG) electrodes for neural activity recording

3.2 Graphene-based intracortical electrodes for neural activity recording

4 Conclusion and prospects

The rapid hemostasis and healing of wounds have a very important effect on human life security and physical health. During the treatment process of wounds, careful, targeted, and effective treatment is required to prevent infection and accelerate tissue regeneration. Thus, the research on wound care materials attracted much attention. Among them, bio-based polymer materials extracted from animals and plants or synthesized from bio-based monomers, having the advantages of good physical properties, biological activity, biocompatibility, biodegradability and bioabsorbability, have been modified or drug-loaded by physical or chemical methods to produce hemostatic materials and wound dressings with functions of hemostasis, sterilization, protection and promotion of wound healing. Herein, we review the progress of domestic and foreign research on hemostatic materials and wound dressings based on common bio-based polymers, such as polylactic acid, chitosan, sodium alginate, hyaluronic acid, protein and polyphosphate in recent years from multiple angles of chemical composition, synthetic route, preparation method, material structure, evaluation model and biological activity. And the research level at home and abroad on these hemostatic materials from bio-sourced and renewable natural resources is also analyzed and compared. Predictably, the main research directions will still be further broadening the types of raw materials as well as making multifunctional and biomimetic materials.

Contents

1 Introduction

2 Polylactic acid materials

2.1 Polylactic acid

2.2 Polylactic acid-Polyethylene glycol

2.3 Poly(lactic acid-co-glycolic acid)

2.4 Other modified PLAs

3 Polysaccharides

3.1 Chitosans

3.2 Alginates

3.3 Hyaluronic acids

3.4 Celluloses

4 Proteins and polypeptides

5 Polyphosphates

6 Conclusion and outlook

Poly(vinylidene fluoride)(PVDF)-based fluoropolymers have received widespread attention due to their unique properties. Poly(vinylidene fluoride)(PVDF)-based fluoropolymers have received widespread attention due to their unique properties. Incorporation of functional segments on PVDF-based fluoropolymers has been an important way to improve their performance and expand the application areas. Compared with the physical blending and the direct copolymerization approaches, significant advantages have been witnessed by employing the graft modification method, which provides an easy and efficient way to obtain well-defined fluoro-copolymer with precise compositions. This review highlights the methods of functional graft modification of PVDF-based fluoropolymers via living radical polymerization (including atom transfer radical polymerization (ATRP), single electron transfer-living radical polymerization (SET-LRP), organocatalyzed atom transfer radical polymerization (O-ATRP), photo-induced Cu(Ⅱ)-mediated reversible deactivation radical polymerization (RDRP) and high energy ray radiation (γ-ray, ultraviolet, electron beam)). The opportunities and applications are proposed for the further development.

Contents

1 Introduction

2 Graft modification of PVDF-based fluoropolymers via atom transfer radical polymerization(ATRP)

2.1 Graft modification of PVDF via ATRP

2.2 Graft modification of P(VDF-co-CTFE) via ATRP

2.3 Graft modification of poly(chlorotrifluoroethyl-ene)(PCTFE) via ATRP

2.4 Graft modification of poly(vinylidene fluoride-co-trifluoroethylene-co-chlorotrifluoroethylene)(P(VDF-co-TrFE-co-CTFE)) via ATRP

2.5 Graft modification of P(VDF-co-HFP) via ATRP

3 Graft modification of PVDF-based fluoropolymers via single electron transfer-living radical polymerization(SET-LRP)

3.1 Graft modification of PVDF via SET-LRP

3.2 Graft modification of P(VDF-co-CTFE) via SET-LRP

4 Graft modification of PVDF-based fluoropolymers via photo-induced Cu(Ⅱ)-mediated RDRP

4.1 Graft modification of PVDF via photo-induced Cu(Ⅱ)-mediated RDRP

4.2 Graft modification of P(VDF-co-CTFE) via photo-induced Cu(Ⅱ)-mediated RDRP

5 Graft modification of PVDF-based fluoropolymers via organocatalyzed atom transfer radical polymerization(O-ATRP)

6 Graft modification of PVDF-based fluoropolymers via radical polymerization

6.1 Graft modification of PVDF via reaction of initiator and double bond

6.2 Graft modification of PVDF via irradiation

7 Conclusion and outlook

Lithium selenium batteries are very promising next-generation high-energy-density batteries with the properties of high theoretical volume energy density(3253 mAh·cm^-3), high electrical conductivity(1×10^-3 S·m^-1),and environmental friendliness, which have gradually become a research hotspot in the field of electrochemistry. However, at present, lithium selenium batteries still face many problems such as low utilization rate of active materials, low coulomb efficiency, fast capacity decay and shuttle of polyselenides intermediates. In recent years, worldwide researchers have conducted a lot of researches on these issues. For example, a variety of carbon materials, metal compounds, selenium alloys, etc. have been used for packaging modification at the positive electrode. Solid electrolyte interface methods have been used for protection at the negative electrode. We comprehensively review the latest research progress of lithium selenium batteries in cathode, anode, electrolytes, separators, binders, current collectors, etc. especially summarize the sealing of nano selenium, the preparation of solid electrolyte protective layer, the research on multifunctional separators and the application of various binders and current collectors. Finally, we prospect the future development and commercial applications of lithium selenium batteries.

Contents

1 Introduction

2 Electrochemical principles of Li-Se batteries

3 Cathode materials

3.1 Selenium/carbon composite electrodes

3.2 Selenium/auxiliary additive composite electrodes

3.3 Metal compound electrodes

3.4 Selenium alloy composite electrodes

4 Anode materials

4.1 Electrolyte additives

4.2 Protective layer(SEI method)

4.3 Anode modification

5 Lithium selenium battery electrolytes

5.1 Liquid electrolytes

5.2 Solid electrolytes

6 Multifunctional separator and separation of cathode and anode

7 Binder

7.1 Selenium cathode binder

7.2 Binderless

8 Current collectors

8.1 Current collectors' classification

8.2 Current collectors' application

9 Conclusion and outlook

9.1 Cathode material

9.2 Anode material

9.3 Other

9.4 Application and Commercialization

9.5

Prospect

With the development of science and technology, great progress has been made in portable electronic products, especially in wearable devices. Flexible battery, as the core component of portable electronic products, has attracted attention of more and more researchers. Lithium-ion battery is used as the main power source in a variety of products because of its good cycle performance and long life span. In order to make portable electronic products flexible and miniaturized, the development of flexible lithium-ion batteries with high energy density can be an urgent issue. Flexible electrode materials are regarded as the important research direction because they are key materials for flexible lithium-ion battery. The article describes recent progress on researches about electrode materials for flexible lithium-ion battery, including integrated flexible electrode and new macro-flexibility electrode structure design. The carbon-based materials and Mxene-based materials all belong to integrated flexible electrode with electrochemical activity. The polymer-based materials, textile-based materials and metal-based materials all belong to integrated flexible electrode based on non-electrochemical activity. The new macro-flexibility electrode structure design meets the needs that wearable devices are woven and tolerable of large scale deformation. This paper analyzes and discusses existing problems of flexible electrodes in order to provide new ideas for researches about flexible lithium-ion battery with high energy density in future.

Contents

1 Introduction

2 Integrated flexible electrode design

2.1 Based material with electrochemical active

2.2 Other non-electrochemical activity based material

3 Macro-flexible electrode structure design

3.1 Kirigami structure

3.2 Fiber structure

4 Conclusion and outlook

Aqueous zinc-ion batteries(AZIBs) have a broad application prospect in large-scale energy storage field with low cost, high safety and high environmental friendliness characteristics. At present, the cathode materials which have attracted much attention have become the research hotspot. Manganese-based compound is one of the most promising cathode materials in the market due to the advantages of abundant resources, environmental friendliness and low price. In this paper, the structural characteristics of different manganese-compounds and manganese-based AZIBs involved four kinds of energy storage mechanisms in the charging and discharging process are reviewed in detail, and the existing problems and optimization strategies of AZIBs manganese-based cathode materials are discussed. Finally, the possible research direction of AZIBs cathode materials is proposed, which is expected to play a certain role in the development of AZIBs.

Contents

1 Introduction

2 Manganese-based cathode materials for aqueous zinc ion batteries

2.1 MnO₂

2.2 Mn₂O₃

2.3 Mn₃O₄

2.4 MnO

2.5 Other manganese compounds

3 Energy storage mechanism of manganese-based aqueous zinc ion batteries

3.1 Zn²⁺ insertion/extraction mechanism

3.2 Chemical conversion reaction mechanism

3.3 Zn²⁺ and H⁺ co-insertion/co-extraction

3.4 Dissolution/deposition mechanism

4 Problems and optimization strategies of manganese-based cathode materials

4.1 Doping

4.2 Surface modification

4.3 Introduction of defects

4.4 “Pillar” effect

4.5 Composite

4.6 Structural design

4.7 Electrolyte optimization

4.8 Other strategies

5 Conclusion and outlook

Due to the controllable nanoscale channels and unique separation performance, the separation films assembled from graphene oxide(GO) nanosheets are promising separation materials, but the unsatisfactory mechanical properties restrict their practical application. Introducing particles such as active molecules and cations between the GO nanosheets can improve the mechanical properties of the GO membranes due to the formation of the stable bonding. In this review, the recent progress on the methods for improving the mechanical properties of GO membranes is summarized. According to the bonding mode between GO and the introduced particles, these methods can be divided into two types, covalent bonding and non-covalent bonding. Furthermore, covalent bonding methods can be divided into macromolecular covalent bonding and small molecule covalent bonding, while noncovalent bonding methods include hydrogen bonding, π-π bonding and ionic bonding. Both covalent bonding and noncovalent bonding can significantly improve the mechanical properties of the GO films, while the covalent bonding methods are more effective. Among the covalent bonding methods, the macromolecule covalent bonding is superior to the small molecule covalent bonding. Finally, the major problems of the current methods for enhancing the mechanical property of GO are discussed, and the future prospects is proposed.

Content:

1 Introduction

2 Covalent bonding method

2.1 Small molecule covalent bonding method

2.2 Macromolecular covalent bonding method

3 Noncovalent bonding method

3.1 Ionic bonding method

3.2 Hydrogen bonding method

3.3 π-π bonding method

4 Conclusion and prospect

Protein is a kind of biological macromolecule with stable structure and abundant functional groups. Recently, the development of protein based nanomaterials has raised wide-spread research enthusiasm, especially in environmental remediation. Dopamine, amyloid-fibrils and protein-inorganic hybrid nanoflower are the three most representative ones. Inspired by mussels, the strong adhesive polydopamine coating forms in alkaline condition through self-polymerization, which is widely used in surface modification. Amyloid-fibrils, obtained by the heat treatment or chemical denaturation of functional protein, possess the large aspect ratio and more active sites for enhancing the decontamination. Besides, the three-dimensional structure of protein makes it easy to form hybrid nanoflower with metallic phosphate. The protein nanoflower provides high surface area for wastewater purification with the assistance of the metallic phosphate. Based on the structural properties of protein, this review summarizes the fabrication, formation mechanism and applications of above three nanomaterials in water pollution control, providing reference to the subsequent scientific study.

Contents

1 Introduction

2 Mussel-inspired dopamine coating and its application

2.1 Preparation and polymerization mechanism of dopamine

2.2 Modification and application of dopamine in environmental protection

3 The structure and environmental application of amyloid-fibrils

3.1 Physicochemical properties and fabrication of amyloid-fibrils

3.2 The environmental applications of amyloid-fibrils

4 Preparation and application of protein induced nanoflower

4.1 Formation and characterization of protein-nanoflower

4.2 Application of protein nanoflower in the field of environment protection

5 Conclusion and outlook

Energetic materials are one kind of special and dangerous energy materials, a huge amount of energy is stored in their structures, and can be released out in a very short time under the external stimulus like thermal, impact, friction and so on. Thus, they play a very unique but important role in the fields of national defense and civil industry. The azole-based metal complex and its polymers have been widely used in many fields of energetic materials such as the primary explosive, the high energy explosive, the rocket propellant and the firework. They have attracted more and more attention of energetic materials scientists from all over the world in recent years, and many different kinds of novel azole-based metal complexes have been designed, synthesized and reported. Therefore, in the present work, first of all, the theoretical design, experimental synthesis, performance evaluation and practical implications of imidazoles, pyrazoles, triazoles, tetrazoles, pentazoles-based energetic metal complexes have been reviewed. Then, some advanced strategies used to regulate the structure, optimize the synthesis and improve the performance are classified, while several existing problems are analyzed also. Finally, some potential development directions on the further theoretical and experiment investigations are pointed out.

Contents

1 Introduction

2 Synthesis and properties of imidazole metal complexes

3 Synthesis and properties of pyrazole metal complexes

4 Synthesis and properties of triazole metal complexes

4.1 Nitro/aminotriazole metal complexes

4.2 Bridged triazole metal complexes

4.3 Azacyclo-substituted triazole metal complexes

5 Synthesis and properties of tetrazole metal complexes

5.1 Aminotetrazole metal complexes

5.2 Bridged tetrazole metal complexes

5.3 Azacyclo-substituted tetrazole metal complexes

6 Synthesis and properties of pentazole metal complexes

7 Theoretical study of azole-based metal complexes

8 Conclusion and outlook