Click Chemistry Research Articles

Polyacrylonitrile nanofibrous mat modified with cysteamine and ionic liquid as a recyclable and efficient adsorbent for selective removal of sulfonamides and Cu(II) from aqueous solution: Roles of multi-function adsorption

The combined contamination of heavy metals and antibiotics is a prevalent occurrence, yet the distinct chemical characteristics of these substances pose a significant obstacle to their simultaneous elimination. In this work, novel polyacrylonitrile nanofibrous mat (NFsM) modified with cysteamine and ionic liquid (IL@Cys@PAN NFsM) was developed using a cascade thiol-ene click reaction. The IL@Cys@PAN NFsM exhibits a rich array of functional groups and demonstrates strong binding affinity, fast mass transfer, and exceptional selectivity for sulfonamides (SAs) and Cu(II). The maximum adsorption capacities for SAs and Cu(II) in single-component systems were 122.3 and 97.4 mg/g respectively, according to the Langmuir isotherm model. The time dependent adsorption capacities followed a pseudo-second-order kinetic model, demonstrating a chemisorption-dominant process for each analyte. In binary pollutant systems, the co-occurrence of SAs and Cu(II) in water produced a competitive effect; however, the decrease in adsorption capacity was minimal. Through experimental analysis, FTIR characterization and density functional theory (DFT) studies, reasonable interactions of hydrogen-bond, electrostatic interactions, π-π stacking for SAs, and chelation effect for Cu(II) were proposed. Additionally, the reusability and recyclability of IL@Cys@PAN NFsM enhance its practicality for real-world applications. This paper presents the first systematic study on the simultaneous adsorption of heavy metals and antibiotics using NFsM, offering a novel perspective on the design of custom adsorbents capable of efficiently removing multiple contaminants with diverse characteristics while balancing eco-friendliness, excellent adsorption performance, and impressive recyclability for wastewater remediation.

Multi‐Level Wettability Patterned Porous Matrix for Advanced Optical Information Encryption

AbstractIn the rapidly evolving landscape of information security, the demand for optical encryption techniques based on wettability patterning, which allows decryption without sophisticated devices and complex procedures, is progressively increasing. However, conventional approaches based on binary wettability patterned surfaces impose significant constraints in their practical use for high‐level information security. Herein, a novel approach to optically encrypt information through multi‐level wettability patterning is introduced on a porous polymer matrix synthesized from vinyl methacrylate (VMA) and poly(ethylene glycol) diacrylate (PEGDA). By employing the thiol‐ene click reaction, precise patterning of functional groups is achieved that exhibit distinct wettability responses to aqueous solutions with varying surface tensions, as well as pH‐responsive and fluorescent markers. This multi‐level wettability system surpasses traditional binary hydrophilic/hydrophobic patterns by providing enhanced control over wettability states, resulting in higher‐level encryption of information. The integration of pH and fluorescence responsivity further elevates the complexity and security of the encrypted information, making it decipherable only under specific and controlled conditions. The innovative approach offers a highly secure, robust, and customizable encryption method, redefining the potential of optical encryption technologies.

Design and synthesis of new coumarin-1,2,3-triazole hybrids as new antidiabetic agents: In vitro α-amylase, α-glucosidase inhibition, anti-inflammatory, and docking study

The current study focuses on the synthesis of coumarin-triazole hybrids (7i-t) starting from 4-hydroxy benzaldehyde or 4-hydroxyacetophenone (1a-b) and propargyl bromide. On the other hand, coumarin derivatives (5c-h) were prepared by Pechmann cyclization and treated with sodium azide to give the corresponding 3-azido methyl coumarins (6c-h). Finally, 1,3-dipolar cycloaddition between compounds 6c-h and terminal alkyne 2a-b produces coumarin-triazole hybrids (7i-t) utilizing click chemistry approaches that are high yielding, wide in scope and simple to perform. The structural proofs of the newly synthesized coumarin-triazole hybrids (7i-t) are proved by various spectroscopic techniques, including IR, 1H NMR, 13C NMR, and LC-MS. The synthesized new coumarin triazole hybrids (7i-t) were explored for their antihyperglycemic potential and therefore evaluated for α-glucosidase and α-amylase inhibitory activities along with anti-inflammatory. The results suggest that among the series, compound 7l showed excellent activity with an IC50 value of 0.67±0.014 mg/mL and 0.72±0.012 mg/mL for α-amylase, and α-glucosidase inhibitory potential while compound 7o showed promising anti-inflammatory activity with IC50 value of 0.54±0.003 mg/mL. To support the above findings, molecular docking studies were performed, which confirmed the interaction of the synthesized molecules 7i-t with an effective binding energy of -9.0 to -10.6 kcal/mol at the active site of the enzyme human pancreatic α-amylase (PDB ID: 1B2Y). Therefore, these scaffolds have the potential to function as lead candidates for antidiabetic and anti-inflammatory activities.

Self-cascade ROS-trapping bioreaction system reverses stem cell oxidative stress fate for osteogenesis

eactive oxygen species (ROS) scavenging is essential for periodontal regeneration. However, the dynamic change of the applied materials within the ROS-rich environment and the residual oxidation products in the host highly impact periodontal regeneration. This study successfully constructs a bioreaction system via thiol-ene click chemistry, leveraging the high affinity of glutathione (GSH) for ROS to attract excess ROS to the crosslinking points. Two minutes after hydrogen peroxide (H2O2) treatment, the ROS level in the G8-0 hydrogel acutely decreases, reaching a 4.4% reduction within 10minutes, confirming the ROS-trapping efficacy. Through a ‘bait switch-on’ mechanism, hexagonal boron nitride (hBN) takes over the captured ROS and the oxidation products of pectin further drive the reduction reaction, ultimately restoring the extracellular environment. The self-cascade products, oxidized hBN, reshape the intracellular oxidative stress (OS) environment, achieving a synergistic extra- and intra-cellular treatment. The significantly high reduced to oxidized glutathione (GSH/GSSG) ratio in G8-10 hydrogel (~80%) illustrates a reversal of oxidative stress in bone marrow stem cells (BMSCs). On a molecular level, the bioreaction system inhibits the NF-κB pathway, promoting the expression of key antioxidant genes (Nqo1 and Nrf2) and osteogenic molecules (ALP and OCN), thereby reversing the detrimental effects of OS on BMSCs. In vivo application demonstrated the system’s strong redox-balancing and osteogenic capabilities in the periodontal inflammation environment. This novel antioxidant bioreaction system, characterized by self-cascade ROS-trapping and product utilization, offers innovative treatment strategies for tissue regeneration under conditions of excessive OS.

Engineered endothelium-mimicking antithrombotic surfaces via combination of nitric oxide-generation with fibrinolysis strategies

Thrombosis associated with implants can severely impact therapeutic outcomes and lead to increased morbidity and mortality. Thus, developing blood-contacting materials with superior anticoagulant properties is essential to prevent and mitigate device-related thrombosis. Herein, we propose a novel single-molecule multi-functional strategy for creating blood-compatible surfaces. The synthesized azide-modified Cu-DOTA-(Lys)3 molecule, which possesses both NO release and fibrinolysis functions, was immobilized on material surfaces via click chemistry. Due to the specificity, rapidity, and completeness of click chemistry, the firmly grafted Cu-DOTA-(Lys)3 endows the modified material with excellent antithrombotic properties of vascular endothelium and thrombolytic properties of fibrinolytic system. This surface effectively prevented thrombus formation in both in vitro and in vivo experiments, owing to the synergistic effect of anticoagulation and thrombolysis. Moreover, the modified material maintained its functional efficacy after one month of PBS immersion, demonstrating excellent stability. Overall, this single-molecule multifunctional strategy may become a promising surface engineering technique for blood-contacting materials.

Algae-based self-driven microrobot for efficient removal of nanoplastics from water environment

Nanoplastics (NPs) have the characteristics of various species, wide distribution, low concentration and difficult degradation. In recent years, the researches of NPs have mainly focused on its toxicity, origin and migration, and the quantitative detection and removal technology of NPs is an urgent technical problem to be solved. Here, an active biohybrid microrobots (DPA-algae robots, diphenolic acids-alage robots) was designed and developed for dynamic removal of NPs in water environment. Firstly, diphenolic acids were functionalized on algae to realize the specific adsorption of nanoplastics through hydrophobic force, electrostatic attraction and van der Waals force between diphenolic acids and nanoplastic particles. Secondly, to realize the rapid identification of NPs, the functionalized algae were assembled into microrobots through rapid click chemistry reaction, thus the self-propulsion ability of algae can be utilized to accelerate the identification and enrichment of target objects. The removal rate of nanoplastics by microalgae robots has increased to 83.1 % at the concentration of 0.125 mg/mL within 2 h compared with the unmodified algae, which is a very significant improvement. In addition, the removal rate was 84.1 % to 87.7 % in different media, so the dynamic removal of NPs is expected to be applied into the filtration process of waterworks by preparing a large number of algae-based microrobots. This multi-functional microrobot is cost-effective and biocompatible, providing a new solution to the global “plastic crisis”.

SO2F2 mediated click chemistry enables modular disulfide formation in diverse reaction media

The dynamic disulfide linkage plays a vital role in various biological processes as well as drugs and biomaterials. The conversion of thiols to their corresponding disulfides is a hallmark of sulfur chemistry, but notoriously difficult to control. Achieving optimal reactivity and selectivity continues to pose significant challenges. Here, we describe a click chemistry for disulfide formation from thiols in both batch and flow-mode using SO2F2, which display exceptional selectivity toward disulfide formation through an effective nucleophilic substitution cascade. This reaction’s unique characteristics satisfy the stringent click-criteria with its high thermodynamic driving force, straightforward conditions, wide scope, quantitative yields, exceptional chemoselectivity, and non-chromatographic purification process. The modular synthesis of symmetrical, unsymmetrical, cyclic and polydisulfides is demonstrated, along with the formation of disulfide cross-linked hydrogels.

Innovative Peptide Bioconjugation Chemistry with Radionuclides: Beyond Classical Click Chemistry.

Background: The incorporation of radionuclides into peptides and larger biomolecules requires efficient and sometimes biorthogonal reaction conditions, to which click chemistry provides a convenient approach. Methods: Traditionally, click-based radiolabeling techniques have focused on classical click chemistry, such as copper(I)-catalyzed alkyne-azide [3+2] cycloaddition (CuAAC), strain-promoted azide-alkyne [3+2] cycloaddition (SPAAC), traceless Staudinger ligation, and inverse electron demand Diels-Alder (IEDDA). Results: However, newly emerging click-based radiolabeling techniques, including tyrosine-click, sulfo-click, sulfur(VI) fluoride exchange (SuFEx), thiol-ene click, azo coupling, hydrazone formations, oxime formations, and RIKEN click offer valuable alternatives to classical click chemistry. Conclusions: This review will discuss the applications of these techniques in peptide radiochemistry.

Design, synthesis, characterization and biological evaluation of coumarin bound 1,2,3-triazoles using click chemistry

In an endeavor to invent new antimalarial and antimicrobial agents, a series of coumarin bound 1,4-disubstituted 1,2,3-triazoles was synthesized through Cu(I)-promoted click reaction between coumarin bound terminal alkynes, that is, 4/7-(prop-2-yn-1-yloxy)-2H-chromen-2-one and 2-azido-N-arylpropanamides. The synthesized 1,2,3-triazoles were characterized by FTIR,1H NMR,13C NMR, and HRMS techniques and were assessed for in vitro antimalarial activity against Plasmodium falciparum as well as in vitro antimicrobial activity against four bacterial strains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Klebsiella pneumoniae) and two fungal strains (Candida albicans, Aspergillus niger). Compound 7o [(N-(4-fluorophenyl)-2-(4-(((2-oxo-2H-chromen-7-yl)oxy)methyl)-1H-1,2,3-triazol-1-yl)propanamide)] displayed better activity against P. falciparum while compound 7y [(N-(3-nitrophenyl)-2-(4-(((2-oxo-2H-chromen-7-yl)oxy)methyl)-1H-1,2,3-triazol-1-yl)propanamide)] displayed excellent activity against all the tested bacterial and fungal strains, amongst the synthesized triazoles. Also, the molecular docking studies of the most potent compounds against DNA gyrase (S. aureus) were also performed to have an insight on binding interactions.

A Scalable Method to Fabricate 2D Hydrogel Substrates for Mechanobiology Studies with Independent Tuning of Adhesiveness and Stiffness.

Mechanical signals from the extracellular matrix are crucial in guiding cellular behavior. Two-dimensional hydrogel substrates for cell cultures serve as exceptional tools for mechanobiology studies because they mimic the biomechanical and adhesive characteristics of natural environments. However, the interdisciplinary knowledge required to synthetize and manipulate these biomaterials typically restricts their widespread use in biological laboratories, which may not have the material science expertise or specialized instrumentation. To address this, we propose a scalable method that requires minimal setup to produce 2D hydrogel substrates with independent modulation of the rigidity and adhesiveness within the range typical of natural tissues. In this method, norbornene-terminated 8-arm polyethylene glycol is stoichiometrically functionalized with RGD peptides and crosslinked with a di-cysteine terminated peptide via a thiol-ene click reaction. Since the synthesis process significantly influences the final properties of the hydrogels, we provide a detailed description of the chemical procedure to ensure reproducibility and high throughput results. We demonstrate examples of cell mechanosignaling by monitoring the activation state of the mechanoeffector proteins YAP/TAZ. This method effectively dissects the influence of biophysical and adhesive cues on cell behavior. We believe that our procedure will be easily adopted by other cell biology laboratories, improving its accessibility and practical application.

Synthesis of lipid‐modified copolymers based on caprolactone via enzymatic ring‐opening polymerization and click chemistry and evaluation of their potential as vehicles in drug delivery

AbstractThis research focuses on the application of click chemistry to the synthesis of amphiphilic lipidic copolymers with a target number of oleyl, cholesteryl, and linoleic pendant groups. The synthesis was performed using a two‐step approach. In the first step, copolymerization of ε‐caprolactone (CL) and α‐azido‐caprolactone (N3CL) was carried out using enzymatic ring‐opening polymerization (eROP) catalyzed by Candida Antarctica lipase B (CALB). This resulted in copolymers with an average molecular weight of 9.53 kDa, each containing approximately seven azide groups per chain. Subsequently, click chemistry was utilized to react P(N3CL‐co‐CL) copolymers with propargylated lipidic compounds, achieving azide group consumption higher than 88%. These lipidic copolymers exhibited reduced crystallinity, as evidenced by their lower melting enthalpy values. In addition, these materials were evaluated for the fabrication of nanostructured vehicles for curcumin (Cur@NP) using the solvent emulsion‐evaporation methodology. The lipidic copolymers demonstrated enhanced encapsulation efficiencies and drug loading capacities of 25 and 12%, respectively, tunable particle sizes in the range of 260–420 nm, and controlled release profiles over 30 h. Cur@NPs demonstrated notable antioxidant and antibacterial activities, particularly against Gram‐positive bacteria such as Staphylococcus aureus, achieving efficiencies close to 50%.

Miniaturized Modular Click Chemistry-enabled Rapid Discovery of Unique SARS-CoV-2 Mpro Inhibitors With Robust Potency and Drug-like Profile.

The COVID-19 pandemic has required an expeditious advancement of innovative antiviral drugs. In this study, focused compound libraries are synthesized in 96- well plates utilizing modular click chemistry to rapidly discover potent inhibitors targeting the main protease (Mpro) of SARS-CoV-2. Subsequent direct biological screening identifies novel 1,2,3-triazole derivatives as robust Mpro inhibitors with high anti-SARS-CoV-2 activity. Notably, C5N17B demonstrates sub-micromolar Mpro inhibitory potency (IC50 = 0.12 µM) and excellent antiviral activity in Calu-3 cells determined in an immunofluorescence-based antiviral assay (EC50 = 0.078 µM, no cytotoxicity: CC50 > 100 µM). C5N17B shows superior potency to nirmatrelvir (EC50 = 1.95 µM) and similar efficacy to ensitrelvir (EC50 = 0.11 µM). Importantly, this compound displays high antiviral activities against several SARS-CoV-2 variants (Gamma, Delta, and Omicron, EC50 = 0.13 - 0.26 µM) and HCoV-OC43, indicating its broad-spectrum antiviral activity. It is worthy that C5N17B retains antiviral activity against nirmatrelvir-resistant strains with T21I/E166V and L50F/E166V mutations in Mpro (EC50 = 0.26 and 0.15 µM, respectively). Furthermore, C5N17B displays favorable pharmacokinetic properties. Crystallography studies reveal a unique, non-covalent multi-site binding mode. In conclusion, these findings substantiate the potential of C5N17B as an up-and-coming drug candidate targeting SARS-CoV-2 Mpro for clinical therapy.

ClickRNA-PROTAC for Tumor-Selective Protein Degradation and Targeted Cancer Therapy.

Proteolysis-targeting chimeras (PROTACs) show promise in tumor treatment. However, the E3 ligases VHL and CRBN, commonly used in PROTAC, are highly expressed in only a few tumors, thus limiting the application scope and efficacy of PROTAC drugs. Furthermore, the lack of tumor specificity in PROTAC drugs can result in toxic side effects. Therefore, there is an urgent need to develop tumor-selective PROTAC drugs that do not rely on endogenous E3 ligases. In this study, we introduce the ClickRNA-PROTAC system, which involves the expression of a fusion protein of the E3 ubiquitin ligase SIAH1 and SNAPTag through mRNA transfection and recruits the protein of interest (POI) using bio-orthogonal click chemistry. ClickRNA-PROTAC can effectively degrade various proteins such as BRD4, KRAS, and NFκB simply by replacing the warhead molecules. By employing a tumor-specific mRNA-responsive translation strategy, ClickRNA-PROTAC can selectively degrade POIs in tumor cells. Furthermore, ClickRNA-PROTAC demonstrated strong efficacy in targeted cancer therapy in a xenograft mouse model of adrenocortical carcinoma. In conclusion, this approach offers several advantages, including independence from endogenous E3 ubiquitin ligases, tumor specificity, and programmability, thereby paving the way for the development of PROTAC drugs.

Catalytic Cycloaddition Reactions of Ynol and Thioynol Ethers

Comprehensive SummaryElectron‐rich alkynes, such as ynol and thioynol ethers, have proven to be versatile and appealing partners in catalytic cycloaddition reactions, and thus have raised considerable attentions owing to the practical application in the modular assembly of valuable carbo‐ and heterocycles. The past decades have witnessed inspiring advances in this emerging field, and an increasing number of related discoveries have been exploited. Divided into two main sections on the basis of substrate type, in each section this comprehensive review will initially summarize their synthetic preparations and subsequently examine their reactivity in every sort of catalytic cycloaddition with emphasis on the methodology development, aimed at providing an access to this burgeoning area and encouraging further innovations in the near future. Key ScientistsFor the cycloaddition of ynol ethers, in 2004, Kozmin et al. firstly developed a silver‐catalyzed [2 + 2] cycloaddition of siloxy alkynes with electron‐poor olefins. In 2012, Hiyama et al. realized a palladium‐catalyzed formal [4 + 2] annulation of alkynyl aryl ethers with internal alkynes. In the same year, Sun et al. discovered an efficient [6 + 2] cyclization between siloxy alkynes and 2‐(oxetan‐3‐yl)benzaldehydes by applying HNTf2 as catalyst. In 2017, Wender et al. first utilized vinylcyclopropanes (VCPs) as coupling partners in the [5 + 2] annulation of ynol ethers. In 2018 and 2020, Ye et al. reported zinc‐catalyzed formal [3 + 2] and [4 + 3] cycloaddition, respectively. For the cycloaddition of thioynol ethers, in 2004, Hilt et al. realized a [4 + 2] cycloaddition by employing the alkynyl sulfides and acyclic 1,3‐dienes. In 2006, a ruthenium‐catalyzed [2 + 2] cycloaddition of thioynol ethers with bicyclic alkenes was accomplished by Tam. In 2014, Sun et al. reported an elegant iridium‐catalyzed click reaction of thioalkynes with azides.

Mesenchymal stem cell-delivered paclitaxel nanoparticles exhibit enhanced efficacy against a syngeneic orthotopic mouse model of pancreatic cancer

Pancreatic cancer is considered the deadliest among various solid tumors, with a five-year survival rate of 13 %. One of the major challenges in the management of advanced pancreatic cancer is the inefficient delivery of chemotherapeutics to the tumor site. Even though nanocarriers have been developed to improve tumoral delivery of chemotherapeutics, less than 1 % of the drugs reach tumors, rendering inadequate concentration for effective inhibition of tumors. As a potential alternative, mesenchymal stem cells (MSCs) can effectively deliver their cargo to tumor sites because of their resistance to chemotherapeutics and inherent tumor tropism. In this study, we used MSCs for the delivery of dibenzocyclooctyne (DBCO)-functionalized paclitaxel (PTX)-loaded poly(lactide-co-glycolide)-b-poly (ethylene glycol) (PLGA) nanoparticles. MSCs were modified to generate artificial azide groups on their surface, allowing nanoparticle loading via endocytosis and surface conjugation via click chemistry. This dual drug loading strategy significantly improves the PTX-loading capacity of azide-expressed MSCs (MSC-Az, 55.4 pg/cell) compared to unmodified MSCs (28.1 pg/cell). The in vitro studies revealed that PTX-loaded MSC-Az, nano-MSCs, exhibited cytotoxic effects against pancreatic cancer without altering their inherent phenotype, differentiation abilities, and tumor tropism. In an orthotopic pancreatic tumor model, nano-MSCs demonstrated significant inhibition of tumor growth (p < 0.05) and improved survival (p < 0.0001) compared to PTX solution, PTX nanocarriers, and Abraxane. Thus, nano-MSCs could be an effective delivery system for targeted pancreatic cancer chemotherapy and other solid tumors.

Water‐Involved Carbon‐Nitrogen Triple‐Bond Monomer Based Polymerization toward Processable Functional Polyamides under Ambient Conditions

AbstractPolyamide plays a pivotal role in engineering thermoplastics. Constrained by the harsh conditions and arduous procedures for its industrial synthesis, developing facile synthesis of polyamides is still challengeable and holds profound significance. Herein, we successfully utilized water as one of the monomers to synthesize functional polyamides under ambient conditions. A powerful multicomponent polymerization of water, isocyanides, and chlorooximes was established in phosphate‐buffered saline. Soluble and thermally stable polyamides with high weight‐average molecular weights (up to 53 900) were obtained in excellent yields (up to 95 %). The polymerization exhibits unique polymerization‐induced emission characteristics, successfully converting non‐emissive monomers into unconventional emissive polymers. Notably, the resultant polyamides could undergo effective post‐modification via the hydroxyl‐yne click reaction. By incorporating various functional groups into the polyamide, its emission color could be fine‐tuned from blue to green and to red. Remarkably, the refractive index (n) of the polyamide at 589 nm could be increased from 1.6173 to 1.7227 and the Δn could be unprecedentedly as high as 0.1054 for non‐heavy atom‐containing polymers after post‐modification, and its micron‐thick films exhibited excellent transparency in the visible region. Thus, this work not only establishes a powerful polymerization toward novel polyamides but also opens up an avenue for their versatile functionalization.

Water-Involved Carbon-Nitrogen Triple-Bond Monomer Based Polymerization toward Processable Functional Polyamides under Ambient Conditions.

Polyamide plays a pivotal role in engineering thermoplastics. Constrained by the harsh conditions and arduous procedures for its industrial synthesis, developing facile synthesis of polyamides is still challengeable and holds profound significance. Herein, we successfully utilized water as one of the monomers to synthesize functional polyamides under ambient conditions. A powerful multicomponent polymerization of water, isocyanides, and chlorooximes was established in phosphate-buffered saline. Soluble and thermally stable polyamides with high weight-average molecular weights (up to 53 900) were obtained in excellent yields (up to 95 %). The polymerization exhibits unique polymerization-induced emission characteristics, successfully converting non-emissive monomers into unconventional emissive polymers. Notably, the resultant polyamides could undergo effective post-modification via the hydroxyl-yne click reaction. By incorporating various functional groups into the polyamide, its emission color could be fine-tuned from blue to green and to red. Remarkably, the refractive index (n) of the polyamide at 589 nm could be increased from 1.6173 to 1.7227 and the Δn could be unprecedentedly as high as 0.1054 for non-heavy atom-containing polymers after post-modification, and its micron-thick films exhibited excellent transparency in the visible region. Thus, this work not only establishes a powerful polymerization toward novel polyamides but also opens up an avenue for their versatile functionalization.

Trends in Injectable Biomaterials for Vocal Fold Regeneration and Long-Term Augmentation.

Human vocal folds (VF), a pair of small, soft tissues in the larynx, have a layered mucosal structure with unique mechanical strength to support high-level tissue deformation by phonation. Severe pathological changes to VF have causes including surgery, trauma, age-related atrophy, and radiation, and lead to partial or complete communication loss and difficulty in breathing and swallowing. VF glottal insufficiency requires injectable VF biomaterials such as hyaluronan, calcium hydroxyapatite, and autologous fat to augment VF functions. Although these biomaterials provide an effective short-term solution, significant variations in patient response and requirements of repeat reinjection remain notable challenges in clinical practice. Tissue engineering strategies have been actively explored in the search of an injectable biomaterial that possesses the capacity to match native tissue's material properties while promoting permanent tissue regeneration. This review aims to assess the current status of biomaterial development in VF tissue engineering. The focus will be on examining state-of-the-art techniques including modification with bioactive molecules, cell encapsulation, composite materials, as well as, in situ crosslinking with click chemistry. We will discuss potential opportunities that can further leverage these engineering techniques in the advancement of VF injectable biomaterials.

Preparation of ultraviolet‐cured silicone elastomer reinforced by SH‐POSS crosslinker for light emitting diode encapsulant

AbstractStable silicone encapsulants are essential for protecting high‐power light‐emitting diodes (LED) from dust and moisture and extending their service life. Herein, by incorporating thiol‐functionalized polyhedral oligomeric silsesquioxane (SH‐POSS) as a crosslinker into ultraviolet‐curable silicone elastomer (UVSE), a series of new UV‐cured silicone encapsulants (SH‐POSS/UVSE) have been developed through thiol‐ene click chemistry. It was found that SH‐POSS effectively enhanced the mechanical properties of SH‐POSS/UVSE. When 30 mol% SH‐POSS was added, the tensile strength and elongation at break reached 1.01 MPa and 422%, respectively, 2.1 and 1.6 times higher than pure UVSE. This could be ascribed to the more concentrated crosslinking network and the improved interfacial interactions between SH‐POSS and UVSE than physical blending. Moreover, the steric effect of branched and rigid SH‐POSS restricted the movement of UVSE molecular chains. Incorporating SH‐POSS also suppressed UVSE degradation and improved its thermal stability. Additionally, when the LED sample encapsulated by SH‐POSS/UVSE‐30 was immersed in boiling red ink for 2 h, no crack or stain was observed, indicating that SH‐POSS/UVSE‐30 possessed good adhesion to the LED lead frame. This work provides a new approach to fabricating high‐strength and stable silicone composites, which are promising candidates as LED encapsulants.

Graphene-Oxide Peptide-Containing Materials for Biomedical Applications.

This review explores the application of graphene-based materials (GBMs) in biomedicine, focusing on graphene oxide (GO) and its interactions with peptides and proteins. GO, a versatile nanomaterial with oxygen-containing functional groups, holds significant potential for biomedical applications but faces challenges related to toxicity and environmental impact. Peptides and proteins can be functionalized on GO surfaces through various methods, including non-covalent interactions such as π-π stacking, electrostatic forces, hydrophobic interactions, hydrogen bonding, and van der Waals forces, as well as covalent bonding through reactions involving amide bond formation, esterification, thiol chemistry, and click chemistry. These approaches enhance GO's functionality in several key areas: biosensing for sensitive biomarker detection, theranostic imaging that integrates diagnostics and therapy for real-time treatment monitoring, and targeted cancer therapy where GO can deliver drugs directly to tumor sites while being tracked by imaging techniques like MRI and photoacoustic imaging. Additionally, GO-based scaffolds are advancing tissue engineering and aiding tissues' bone, muscle, and nerve tissue regeneration, while their antimicrobial properties are improving infection-resistant medical devices. Despite its potential, addressing challenges related to stability and scalability is essential to fully harness the benefits of GBMs in healthcare.