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An unusual self‐assembly pattern is observed for highly ordered 1500‐nm‐thick films of monodisperse 13‐nm‐sized colloidal PbSe quantum dots, originating from their faceted truncated cube‐like shape. Specifically, self‐assembled PbSe dots exhibited attachment to the substrate by <001> planes followed by an interconnection through the {001} facets in plan‐view and {110}/{111} facets in cross‐sectional‐view, thus forming a cubic superlattice. The thermoelectric properties of the PbSe superlattice thin films are investigated by means of frequency domain thermoreflectance, scanning thermal probe microscopy, and four‐probe measurements, and augmented by computational efforts. Thermal conductivity of the superlattice films is measured as low as 0.7 W m−1 K−1 at room temperature due to the developed nanostructure. The low values of electrical conductivity are attributed to the presence of insulating oleate capping ligands at the dots’ surface and the small contact area between the PbSe dots within the superlattice. Experimental efforts aiming at the removal of the oleate ligands are conducted by annealing or molten‐salt treatment, and in the latter case, yielded a promising improvement by two orders of magnitude in thermoelectric performance. The result indicates that the straightforward molten‐salt treatment is an interesting approach to derive thermoelectric dot superlattice thin films over a centimeter‐sized area. [ABSTRACT FROM AUTHOR]

Inspired by nature, intelligent self‐healing materials have recently been exploited also in the field of photovoltaics to mimic natural systems achieving self‐repairing. The past decade has witnessed perovskite solar cells (PSCs) skyrocketing to a certified power conversion efficiency of 26.1%. However, their intrinsic instability, when exposing to moisture, high temperature, and continuous illumination, hampers their commercial development for a long‐term use in ambient operating conditions. Therefore, the use of smart self‐healing materials, based on self‐assembling properties and dynamic interactions, empowers PSCs with self‐recovery abilities to reinforce their pivotal role as efficient photovoltaic devices and encourage their exploitation in the market. Herein, the current progress in self‐healing perovskite materials with a special focus on self‐recovery after moisture exposure or mechanical damage with the aim to provide a valuable insight for research on this topic to accelerate the PSC commercialization process is highlighted. [ABSTRACT FROM AUTHOR]

The need for chronic systemic immunosuppression, which is associated with unavoidable side-effects, greatly limits the applicability of allogeneic cell transplantation for regenerative medicine applications including pancreatic islet cell transplantation to restore insulin production in type 1 diabetes (T1D). Cell transplantation in confined sites enables the localized delivery of anti-inflammatory and immunomodulatory drugs to prevent graft loss by innate and adaptive immunity, providing an opportunity to achieve local effects while minimizing unwanted systemic side effects. Nanoparticles can provide the means to achieve the needed localized and sustained drug delivery either by graft targeting or co-implantation. Here, we evaluated the potential of our versatile platform of drug-integrating amphiphilic nanomaterial assemblies (DIANAs) for targeted drug delivery to an inflamed site model relevant for islet transplantation. We tested either passive targeting of intravenous administered spherical nanomicelles (nMIC; 20–25 nm diameter) or co-implantation of elongated nanofibrils (nFIB; 5 nm diameter and >1 μm length). To assess the ability of nMIC and nFIB to target an inflamed graft site, we used a lipophilic fluorescent cargo (DiD and DiR) and evaluated the in vivo biodistribution and cellular uptake in the graft site and other organs, including draining and non-draining lymph nodes, after systemic administration (nMIC) and/or graft co-transplantation (nFIB) in mice. Localized inflammation was generated either by using an LPS injection or by using biomaterial-coated islet-like bead implantation in the subcutaneous site. A cell transplant inflammation model was used as well to test nMIC- and nFIB-targeted biodistribution. We found that nMIC can reach the inflamed site after systemic administration, while nFIB remains localized for several days after co-implantation. We confirmed that DIANAs are taken up by different immune cell populations responsible for graft inflammation. Therefore, DIANA is a useful approach for targeted and/or localized delivery of immunomodulatory drugs to decrease innate and adaptive immune responses that cause graft loss after transplantation of therapeutic cells. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) have been surfacing as a pivotal platform for vaccine development. In our previous work, we developed a cholera toxin B subunit (CTB)-based self-assembled nanoparticle (CNP) and produced highly promising bioconjugate nanovaccines by loading bacterial polysaccharide (OPS) in vivo. In particular, the Klebsiella pneumoniae O2 serotype vaccine showcased a potent immune response and protection against infection. However, extremely low yields limited its further application. In this study, we prepared an efficient Klebsiella pneumoniae bioconjugate nanovaccine in Escherichia coli with a very high yield. By modifying the 33rd glycine (G) in the CNP to aspartate (D), we were able to observe a dramatically increased expression of glycoprotein. Subsequently, through a series of mutations, we determined that G33D was essential to increasing production. In addition, this increase only occurred in engineered E. coli but not in the natural host K. pneumoniae strain 355 (Kp355) expressing OPSKpO2. Next, T-cell epitopes were fused at the end of the CNP(G33D), and animal experiments showed that fusion of the M51 peptide induced high antibody titers, consistent with the levels of the original nanovaccine, CNP-OPSKpO2. Hence, we provide an effective approach for the high-yield production of K. pneumoniae bioconjugate nanovaccines and guidance for uncovering glycosylation mechanisms and refining glycosylation systems. [ABSTRACT FROM AUTHOR]

[Display omitted] Chronic wounds, particularly those caused by diabetes, pose a significant challenge for clinical treatment due to their prolonged healing process and associated complications, which can lead to increased morbidity. A biocompatible hydrogel with strong antibacterial properties and the ability to promote angiogenesis can be directly absorbed in the wound site for healing. A series of self-healing, antibacterial bolaamphiphilic supramolecular self-assembling hydrogels (HLQMes/Cu) were developed based on metal–ligand coordination between various concentrations of Cu2+ solution and the head group of l -histidine methyl ester in HLQMes. This is the first report on the application of bola-molecular supramolecular hydrogels for the treatment of chronic wounds. The bola-molecular hydrogels reduced the toxicity of copper ions by coordination, and the HLQMes/Cu hydrogel, with 1.3 mg/mL Cu2+ (HLQMes/Cu1.3), demonstrated good biocompatibility and antibacterial properties and effectively enhanced wound healing in a diabetic wound model with full-thickness injuries. Immunohistochemical analysis revealed that the HLQMes/Cu1.3 hydrogel enhanced epithelial formation and collagen deposition in wounds. Immunofluorescence studies confirmed that the HLQMes/Cu1.3 hydrogel attenuated the expression of proinflammatory factor (IL-6) and promoted angiogenesis by upregulating α-SMA and CD31. These findings demonstrate the potential of this bolaamphiphilic supramolecular self-assembling hydrogel as a promising candidate for diabetic wound treatment. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) have been widely utilized in vaccine design. Although numerous NPs have been explored, NPs with adjuvant effects on their own have rarely been reported. We produce a promising self-assembled NP by integrating the pentameric Escherichia coli heat-labile enterotoxin B subunit (LTB) (studied as a vaccine adjuvant) with a trimer-forming peptide. This fusion protein can self-assemble into the NP during expression, and polysaccharide antigens (OPS) are then loaded in vivo using glycosylation. We initially produced two Salmonella paratyphi A conjugate nanovaccines using two LTB subfamilies (LTIB and LTIIbB). After confirming their biosafety in mice, the data showed that both nanovaccines (NP(LTIB)-OPSSPA and NP(LTIIbB)-OPSSPA) elicited strong polysaccharide-specific antibody responses, and NP(LTIB)-OPS resulted in better protection. Furthermore, polysaccharides derived from Shigella or Klebsiella pneumoniae were loaded onto NP(LTIB) and NP(LTIIbB). The animal experimental results indicated that LTIB, as a pentamer module, exhibited excellent protection against lethal infections. This effect was also consistent with that of the reported cholera toxin B subunit (CTB) modular NP in all three models. For the first time, we prepared a novel promising self-assembled NP based on LTIB. In summary, these results indicated that the LTB-based nanocarriers have the potential for broad applications, further expanding the library of self-assembled nanocarriers. [ABSTRACT FROM AUTHOR]

Diamond nanoparticles are an extremely promising class of carbon‐based nanomaterials. Because of their versatility, they have an interest in a large variety of applications, however, their use in the fabrication of enzyme mimics was not previously investigated. In this study, we realized hybrid systems based on guanidinium derivatives and diamond nanoparticles by simple adsorption of the organic material on their surface. The guanidinium derivatives chosen for this study are calix[4]arenes, blocked in the cone conformation via functionalization at the lower rim with alkyl chains, and decorated with guanidinium or arginine units at the upper rim. The corresponding monofunctional counterparts were also investigated as model compounds. These materials were characterized with different experimental techniques, i. e. thermogravimetric analysis, dynamic light scattering, ζ‐potential measurements and IR/Raman spectroscopy. Their catalytic properties in the cleavage of phosphodiesters were investigated by an in‐depth kinetic analysis. The whole experimental picture points to conclude that these compounds are stably adsorbed onto the nanodiamonds surface and are active in the transesterification reaction of the RNA model compound 2‐hydroxypropyl p‐nitrophenyl phosphate in water, with a notable advantage over their catalytic performances at the same concentration in solution. [ABSTRACT FROM AUTHOR]

Industrializing water electrolyzers demands better electrocatalysts, especially for the anodic oxygen evolution reaction (OER). The prevailing OER catalysts are Ir or Ru‐based nanomaterials, however, they still suffer from insufficient stability. An alternative yet considerably less explored approach is to upgrade Rh, a known stable but moderately active element for OER electrocatalysis, via rational structural engineering. Herein, a precise synthesis of assembled RhRuFe trimetallenes (RhRuFe TMs) with an average thickness of 1 nm for boosting overall water splitting catalysis is reported. Favorable mass transport and optimized electronic structure collectively render RhRuFe TMs with an improved OER activity of an overpotential of 330 mV to deliver 10 mA cm−2, which is significantly lower than the Rh/C control (by 601 mV) and reported Rh‐based OER electrocatalysts. In particular, the RhRuFe TMs‐based water splitting devices can achieve the current density of 10 mA cm−2 at a low voltage of 1.63 V, which is among the best in the Rh‐based bifunctional catalysts for electrolyzers. The addition of Fe in RhRuFe TMs can modulate the strain/electron distribution of the multi‐alloy, which regulates the binding energies of H* and OH* in hydrogen and oxygen evolution reactions for achieving the enhanced bifunctional OER and HER catalysis is further demonstrated. [ABSTRACT FROM AUTHOR]

The paper provides a detailed overview of the scientific background, mostly published in 1970s–1990s, which resulted in tremendous success in preparation of modified electrodes, later used for bioelectrochemical, (bio)catalytic, photoelectrocatalytic, and other applications. The systems overviewed in the paper are focused on the chemisorption of sulfur-containing molecules (thiols, disulfides, sulfides, etc.). The self-assembling of these molecules at various metal (mostly Au and Pt) electrodes resulted in the formation of the well-structured monolayers, which allowed unique chemical and electrochemical features, not achievable by other modification techniques. Notably, the present paper is different from other typical reviews and books about chemically modified electrodes—it is not aimed at highlighting the recent achievements in the research area, but provides a detailed analysis of the area background produced about 30–50 years ago. While there are many reviews on the present state-of-the-art (mostly describing specific applications), the background of the research area is not well remembered, particularly by young researchers and students. Therefore, the paper is mainly aimed at educational aspects, rather than highlighting the modern applications, which are only briefly mentioned in the concluding section. The chemical structures exemplified in the paper represent a comprehensive collection of the systems produced by the self-assembling method developed a few decades ago. [ABSTRACT FROM AUTHOR]

Currently, ultrashort oligopeptides consisting of fewer than eight amino acids represent a cutting-edge frontier in materials science, particularly in the realm of hydrogel formation. By employing solid-phase synthesis with the Fmoc/tBu approach, a novel pentapeptide, FEYNF-NH2, was designed, inspired by a previously studied sequence chosen from hen egg-white lysozyme (FESNF-NH2). Qualitative peptide analysis was based on reverse-phase high performance liquid chromatography (RP-HPLC), while further purification was accomplished using solid-phase extraction (SPE). Exact molecular ion confirmation was achieved by matrix-assisted laser desorption–ionization mass spectrometry (MALDI-ToF MS) using two different matrices (HCCA and DHB). Additionally, the molecular ion of interest was subjected to tandem mass spectrometry (MS/MS) employing collision-induced dissociation (CID) to confirm the synthesized peptide structure. A combination of research techniques, including Fourier-transform infrared spectroscopy (FTIR), fluorescence analysis, transmission electron microscopy, polarized light microscopy, and Congo red staining assay, were carefully employed to glean valuable insights into the self-assembly phenomena and gelation process of the modified FEYNF-NH2 peptide. Furthermore, molecular docking simulations were conducted to deepen our understanding of the mechanisms underlying the pentapeptide's supramolecular assembly formation and intermolecular interactions. Our study provides potential insights into amyloid research and proposes a novel peptide for advancements in materials science. In this regard, in silico studies were performed to explore the FEYNF peptide's ability to form polyplexes. [ABSTRACT FROM AUTHOR]

Intimal hyperplasia is a common lesion that can be observed in diverse vascular diseases. Drug-eluting stents and drug-coated balloons, which can release anti-proliferative agents to inhibit smooth muscle cell (SMC) proliferation, are developed to prevent intimal hyperplasia. However, these intervention devices still cannot achieve satisfactory clinical outcomes. In contrast to endovascular drug delivery, vascular adventitial drug delivery is a new strategy. To develop a vascular adventitial drug delivery system to treat intimal hyperplasia post vascular injuries, we loaded miR-145-5p-agomir (miR-145) into an injectable and in-situ self-assembling RAD peptide hydrogel. In vitro data showed that the miR-145 could be well incorporated into the RAD peptide hydrogels and released in a slow and controlled manner. The released miR-145 could transfect SMCs successfully, and the transfected SMCs exhibited a reduced migration capacity and higher expressions of SMC contractile biomarkers as compared to the non-transfected SMCs. In vivo data showed that the retention of the miR-145 was greatly elongated by the RAD peptide hydrogels. In addition, the application of the miR-145-loaded RAD peptide hydrogels surrounding injured arteries decreased the proliferative SMCs, promoted the regeneration of endothelium, reduced the macrophage infiltration, inhibited the neointimal formation and prevented adverse ECM remodeling via downregulation of KLF4 expression. The RAD peptide hydrogels loaded with miR-145 can successfully inhibit intimal hyperplasia after vascular injuries and thus hold great potential as an innovative extravascular drug delivery approach to treat vascular diseases. Intimal hyperplasia is a common lesion that can be observed in diverse vascular diseases. Drug-eluting stents and drug-coated balloons, which can release anti-proliferative agents to inhibit smooth muscle cell (SMC) proliferation, are developed to prevent intimal hyperplasia. However, these intervention devices still cannot achieve satisfactory clinical outcomes. In contrast to endovascular drug delivery, vascular adventitial drug delivery is a new strategy. Our work here demonstrates that the RAD peptide hydrogels loaded with miR-145-5p-agomir (miR-145) can successfully reverse intimal hyperplasia after vascular injuries and thus hold great potential as an innovative vascular adventitial drug delivery approach to treat vascular diseases. Our work proposes a possible paradigm shift from endovascular drug delivery to extravascular drug delivery for vascular disorder treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Inspired by nature, intelligent self‐healing materials have recently been exploited also in the field of photovoltaics to mimic natural systems achieving self‐repairing. The past decade has witnessed perovskite solar cells (PSCs) skyrocketing to a certified power conversion efficiency of 26.1%. However, their intrinsic instability, when exposing to moisture, high temperature, and continuous illumination, hampers their commercial development for a long‐term use in ambient operating conditions. Therefore, the use of smart self‐healing materials, based on self‐assembling properties and dynamic interactions, empowers PSCs with self‐recovery abilities to reinforce their pivotal role as efficient photovoltaic devices and encourage their exploitation in the market. Herein, the current progress in self‐healing perovskite materials with a special focus on self‐recovery after moisture exposure or mechanical damage with the aim to provide a valuable insight for research on this topic to accelerate the PSC commercialization process is highlighted.

Ion signaling through Ca2+ and Na+ plays a key role in mechanotransduction and encourages a chondrogenic phenotype and tissue maturation. In this study, we propose that the pleiotropic effects of Ca2+ and Na+ modulation can be used to induce maturation and improvement of neocartilage derived from redifferentiated expanded chondrocytes from minipig rib cartilage. Three ion modulators were employed: (1) 4α-phorbol-12,13-didecanoate (4-αPDD), an agonist of the Ca2+-permeable transient receptor potential vanilloid 4 (TRPV4), (2) ouabain, an inhibitor of the Na+/K+ pump, and (3) ionomycin, a Ca2+ ionophore. These ion modulators were used individually or in combination. While no beneficial effects were observed when using combinations of the ion modulators, single treatment of constructs with the three ion modulators resulted in multiple effects in structure-function relationships. The most significant findings were related to ionomycin. Treatment of neocartilage with ionomycin produced 61% and 115% increases in glycosaminoglycan and pyridinoline crosslink content, respectively, compared with the control. Moreover, treatment with this Ca2+ ionophore resulted in a 45% increase of the aggregate modulus, and a 63% increase in the tensile Young's modulus, resulting in aggregate and Young's moduli of 567 kPa and 8.43 MPa, respectively. These results support the use of ion modulation to develop biomimetic neocartilage using expanded redifferentiated costal chondrocytes. Impact Statement New cost-effective, replicable, and highly controllable strategies are required to develop neocartilage with biomimetic properties akin to native tissue. Ion signaling plays a key role in mechanotransduction, promoting chondrogenic phenotype. Using rib cartilage, we proposed that Ca2+ and Na+ modulation could be used to induce maturation of neotissue derived from redifferentiated, expanded costal chondrocytes, improving its mechanical properties. Our results indicate that Ca2+ modulation with ionomycin, which stimulated extracellular matrix deposition and collagen crosslinking, improved morphological and mechanical features of neocartilage constructs, and holds potential as a powerful tool to engineer hyaline-like tissues.

Mei Cong,1,&ast; Houjun Pang,1,2,&ast; Guangxing Xie,1 Feifei Li,3 Chunxiao Li,3 Hao Sun,3 Shaoyou Yang,1 Weidong Zhao3 1School of Pharmacy, Xinxiang Medical University, Xinxiang, People’s Republic of China; 2Department of Pharmacy, Dazhou Women and Children’s Hospital, Dazhou, People’s Republic of China; 3Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Weidong Zhao, Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, 453003, People’s Republic of China, Tel +86 0373 3029977, Fax +86 0373 3029977, Email 141051@xxmu.edu.cnPurpose: Molecular targeted therapy is one of the most pivotal strategies in the treatment of non-small cell lung cancer, yet its curative effect is severely compromised by the poor aqueous solubility, low bioavailability and inadequate tumor accumulation of targeted agents. To enhance the efficacy of targeted agents, we demonstrate a novel self-assemble amphiphilic molecule based on erlotinib as an effective nanodrug for anti-cancer treatment.Methods: An amphiphilic molecule composed of hydrophobic erlotinib and hydrophilic biotin block was synthesized and characterized by nuclear magnetic resonance (NMR) as well as high-resolution mass spectrometry (HRMS). Then, nanoassemblies of the amphiphilic molecules are formulated by using nanoprecipitation method. Subsequently, the size, morphology, cell uptake, the anticancer activity and in vivo distribution of the newly constructed erlotinib nanodrug were systematically assessed by some methods, including transmission electron microscopy (TEM), dynamic light-scattering (DLS), flow cytometry, in vivo imaging system etc.Results: We developed a novel nanoformulation of erlotinib, which possesses a high drug loading of 45%. With the features of well-defined structure and small size, the obtained nanodrug could be effectively accumulated in tumor sites and rapidly internalized by cancer cells. Finally, the erlotinib-based nanoformulation showed considerably better anticancer activity compared to free erlotinib both in vitro and in vivo. Moreover, the nanodrug displayed great tolerability.Conclusion: Combining the advantageous features of both nanotechnology and self-assemble, this novel erlotinib nanomedicine constitutes a promising therapeutic candidate for cancer treatment. This study also underlines the potential use of amphiphilic molecule for improving drug efficacy as well as reducing drug toxicity, which could become a general strategy for the preparation of nanodrugs of active agents.Keywords: erlotinib, amphiphilic molecule, self-assembling, drug self-delivery system, non-small cell lung cancer

It is found that the disordered growth of bottom perovskite film deteriorates the buried interface of perovskite solar cells (PSCs), so developing a new material to modify the buried interface for regulating the crystal growth and defect passivation is an effective approach for improving the photovoltaic performance of PSCs. Here, we developed a new ionic liquid crystal (ILC, 1‐Dodecyl‐3‐methylimidazolium tetrafluoroborate) as both crystal regulator and defect passivator to modify the buried interface of PSCs. The high lattice matching between this ILC and perovskite promotes preferential growth of perovskite film along [001] direction, while the oriented ILC with mesomorphic phase has a strong chemical interaction with perovskite to passivate the interface defect, as a result, the modified buried interface exhibits suppressed defects, improved band alignment, reduced nonradiative recombination losses, and enhanced charge extraction. The ILC‐modified PSC delivers a power conversion efficiency of 24.92 % and maintains 94 % of the original value after storage in ambient for 3000 h. [ABSTRACT FROM AUTHOR]

Self‐assembling of peptides is essential for a variety of biological and medical applications. However, it is challenging to investigate the self‐assembling properties of peptides within the complete sequence space due to the enormous sequence quantities. Here, it is demonstrated that a transformer‐based deep learning model is effective in predicting the aggregation propensity (AP) of peptide systems, even for decapeptide and mixed‐pentapeptide systems with over 10 trillion sequence quantities. Based on the predicted AP values, not only the aggregation laws for designing self‐assembling peptides are derived, but the transferability relation among the APs of pentapeptides, decapeptides, and mixed pentapeptides is also revealed, leading to discoveries of self‐assembling peptides by concatenating or mixing, as consolidated by experiments. This deep learning approach enables speedy, accurate, and thorough search and design of self‐assembling peptides within the complete sequence space of oligopeptides, advancing peptide science by inspiring new biological and medical applications. [ABSTRACT FROM AUTHOR]

The nanofibers formed by C 12 H 23 O-(VVKK) 2 V-NH 2 disassembled by dilution, resulting in its high antibacterial activity via bacterial membrane disruption. Comparatively, the nanofibers formed by C 16 H 31 O-(VVKK) 2 V-NH 2 were very stable, which can closely attach on bacterial surface but not permeate bacterial membrane, leading to its low antibacterial activity but high toxicity to human red blood cells. [Display omitted] Lipopeptides have become one of the most potent antibacterial agents, however, there is so far no consensus about the link between their physic-chemical properties and biological activity, in particular their inherent aggregation propensity and antibacterial potency. To this end, we here de novo design a series of lipopeptides (C n H (2n-1) O-(VVKK) 2 V-NH 2), in which an alkyl chain is covalently attached onto the N -terminus of a short cationic peptide sequence with an alternating pattern of hydrophobic VV (Val) and positively charged KK (Lys) motifs. By varying the alkyl chain length (ortho -octanoic acid (C8), lauric acid (C12), and palmitic acid (C16)), the lipopeptides show distinct physicochemical properties and self-assembly behaviors, which have great effect on their antibacterial activities. C 8 H 15 O-(VVKK) 2 V-NH 2 , which contains the lowest hydrophobicity and surface activity has the lowest antibacterial activity. C 12 H 23 O-(VVKK) 2 V-NH 2 and C 16 H 31 O-(VVKK) 2 V-NH 2 both have high hydrophobicity and surface activity, and self-assembled into long nanofibers. However, the nanofibers formed by C 12 H 23 O-(VVKK) 2 V-NH 2 disassembled by dilution, resulting in its high antibacterial activity via bacterial membrane disruption. Comparatively, the nanofibers formed by C 16 H 31 O-(VVKK) 2 V-NH 2 were very stable, which can closely attach on bacterial surface but not permeate bacterial membrane, leading to its low antibacterial activity. Thus, the stability other than the morphologies of lipopeptides' nanostructures contribute to their antibacterial ability. Importantly, this study enhances our understanding of the antibacterial mechanisms of self-assembling lipopeptides that will be helpful in exploring their biomedical applications. [ABSTRACT FROM AUTHOR]

(Hetero)cycloarenes possessing rigid molecular skeletons and large π-systems are the potential active materials in various electronic devices. However, the development of their organic electronics still lags far behind the synthetic chemistry. Herein, in order to bridge this gap, we reported the study of organic semiconductor materials based on heterocycloarenes in detail about the relationship between structure, properties, and device performance. Three varying straight alkyl chain substituted butterfly-shaped heterocycloarenes PTZs were strategically synthesized. Compared with bulky aryl(mesityl) substituted PTZ1, PTZs show additional self-assembly behavior. Concentration-dependent 1H NMR spectra indicated that the self-assembly behavior can be modulated by the alkyl chain length. Medium alkyl chain length substituted heterocycloarene PTZ-C6 showed the strongest association constants of 490 M−1 in solution, and a similar trend was also observed in solid state by thin film absorption spectra. Remarkably, despite the nonplanar conjugated backbones, solution-processing thin film transistor based on PTZ-C6 exhibits hole mobility up to 0.13 cm2 V−1 s−1 and considerable current on/off ratio of 105. Our study demonstrates that substituent engineering of heterocycloarenes is a powerful strategy for modulating self-assembling structures and promoting transistor device performance. [ABSTRACT FROM AUTHOR]

The need for chronic systemic immunosuppression, which is associated with unavoidable side-effects, greatly limits the applicability of allogeneic cell transplantation for regenerative medicine applications including pancreatic islet cell transplantation to restore insulin production in type 1 diabetes (T1D). Cell transplantation in confined sites enables the localized delivery of anti-inflammatory and immunomodulatory drugs to prevent graft loss by innate and adaptive immunity, providing an opportunity to achieve local effects while minimizing unwanted systemic side effects. Nanoparticles can provide the means to achieve the needed localized and sustained drug delivery either by graft targeting or co-implantation. Here, we evaluated the potential of our versatile platform of drug-integrating amphiphilic nanomaterial assemblies (DIANAs) for targeted drug delivery to an inflamed site model relevant for islet transplantation. We tested either passive targeting of intravenous administered spherical nanomicelles (nMIC; 20–25 nm diameter) or co-implantation of elongated nanofibrils (nFIB; 5 nm diameter and >1 μm length). To assess the ability of nMIC and nFIB to target an inflamed graft site, we used a lipophilic fluorescent cargo (DiD and DiR) and evaluated the in vivo biodistribution and cellular uptake in the graft site and other organs, including draining and non-draining lymph nodes, after systemic administration (nMIC) and/or graft co-transplantation (nFIB) in mice. Localized inflammation was generated either by using an LPS injection or by using biomaterial-coated islet-like bead implantation in the subcutaneous site. A cell transplant inflammation model was used as well to test nMIC- and nFIB-targeted biodistribution. We found that nMIC can reach the inflamed site after systemic administration, while nFIB remains localized for several days after co-implantation. We confirmed that DIANAs are taken up by different immune cell populations responsible for graft inflammation. Therefore, DIANA is a useful approach for targeted and/or localized delivery of immunomodulatory drugs to decrease innate and adaptive immune responses that cause graft loss after transplantation of therapeutic cells.

Nanoparticles (NPs) have been surfacing as a pivotal platform for vaccine development. In our previous work, we developed a cholera toxin B subunit (CTB)-based self-assembled nanoparticle (CNP) and produced highly promising bioconjugate nanovaccines by loading bacterial polysaccharide (OPS) in vivo. In particular, the Klebsiella pneumoniae O2 serotype vaccine showcased a potent immune response and protection against infection. However, extremely low yields limited its further application. In this study, we prepared an efficient Klebsiella pneumoniae bioconjugate nanovaccine in Escherichia coli with a very high yield. By modifying the 33rd glycine (G) in the CNP to aspartate (D), we were able to observe a dramatically increased expression of glycoprotein. Subsequently, through a series of mutations, we determined that G33D was essential to increasing production. In addition, this increase only occurred in engineered E. coli but not in the natural host K. pneumoniae strain 355 (Kp355) expressing OPSKpO2. Next, T-cell epitopes were fused at the end of the CNP(G33D), and animal experiments showed that fusion of the M51 peptide induced high antibody titers, consistent with the levels of the original nanovaccine, CNP-OPSKpO2. Hence, we provide an effective approach for the high-yield production of K. pneumoniae bioconjugate nanovaccines and guidance for uncovering glycosylation mechanisms and refining glycosylation systems.

Abstract Background The clinical symptoms of invasive fungal infections (IFI) are nonspecific, and early clinical diagnosis is challenging, resulting in high mortality rates. This study reports the development of a novel aptamer-G-quadruplex/hemin self-assembling color system (AGSCS) based on (1 → 3)-β-D-glucans’ detection for rapid, specific and visual diagnosis of IFI. Methods We screened high affinity and specificity ssDNA aptamers binding to (1 → 3)-β-D-glucans, the main components of cell wall from Candida albicans via Systematic Evolution of Ligands by EXponential enrichment. Next, a comparison of diagnostic efficiency of AGSCS and the (1 → 3)-β-D-glucans assay (“G test”) with regard to predicting IFI in 198 clinical serum samples was done. Results Water-soluble (1 → 3)-β-D-glucans were successfully isolated from C. albicans ATCC 10,231 strain, and these low degree of polymerization glucans (

Abstract Self‐assembling of peptides is essential for a variety of biological and medical applications. However, it is challenging to investigate the self‐assembling properties of peptides within the complete sequence space due to the enormous sequence quantities. Here, it is demonstrated that a transformer‐based deep learning model is effective in predicting the aggregation propensity (AP) of peptide systems, even for decapeptide and mixed‐pentapeptide systems with over 10 trillion sequence quantities. Based on the predicted AP values, not only the aggregation laws for designing self‐assembling peptides are derived, but the transferability relation among the APs of pentapeptides, decapeptides, and mixed pentapeptides is also revealed, leading to discoveries of self‐assembling peptides by concatenating or mixing, as consolidated by experiments. This deep learning approach enables speedy, accurate, and thorough search and design of self‐assembling peptides within the complete sequence space of oligopeptides, advancing peptide science by inspiring new biological and medical applications.

Biomaterials with improved biological features can be obtained by conjugating glycans to nanostructured peptides. Creating peptide‐glycan chimeras requires superb chemoselectivity. We expedite access to such chimeras by merging peptide and glycan solid‐phase syntheses employing a bifunctional monosaccharide. The concept was explored in the context of the on‐resin generation of a model α(1→6)tetramannoside linked to peptides, lipids, steroids, and adamantane. Chimeras containing a β(1→6)tetraglucoside and self‐assembling peptides such as FF, FFKLVFF, and the amphiphile palmitoyl‐VVVAAAKKK were prepared in a fully automated manner. The robust synthetic protocol requires a single purification step to obtain overall yields of about 20 %. The β(1→6)tetraglucoside FFKLVFF chimera produces micelles rather than nanofibers formed by the peptide alone as judged by microscopy and circular dichroism. The peptide amphiphile‐glycan chimera forms a disperse fiber network, creating opportunities for new glycan‐based nanomaterials. [ABSTRACT FROM AUTHOR]

A novel voltammetric sensor based on a self-assembled composite formed by native DNA and electropolymerized N-phenyl-3-(phenylimino)-3H-phenothiazin-7-amine has been developed and applied for sensitive determination of doxorubicin, an anthracycline drug applied for cancer therapy. For this purpose, a monomeric phenothiazine derivative has been deposited on the glassy carbon electrode from the 0.4 M H2SO4-acetone mixture (1:1 v/v) by multiple potential cycling. The DNA aliquot was either on the electrode modified with electropolymerized film or added to the reaction medium prior to electropolymerization. The DNA entrapment and its influence on the redox behavior of the underlying layer were studied by scanning electron microscopy and electrochemical impedance spectroscopy. The DNA–doxorubicin interactions affected the charge distribution in the surface layer and, hence, altered the redox equilibrium of the polyphenothiazine coating. The voltametric signal was successfully applied for the determination of doxorubicin in the concentration range from 10 pM to 0.2 mM (limit of detection 5 pM). The DNA sensor was tested on spiked artificial plasma samples and two commercial medications (recovery of 90–95%). After further testing on real clinical samples, the electrochemical DNA sensor developed can find application in monitoring drug release and screening new antitumor drugs able to intercalate DNA. [ABSTRACT FROM AUTHOR]

Demonstration of efficient polarization‐signal filtering induced by molecular orientation in organic heterostructures remains elusive. Herein, an epitaxial growth technology is developed for blue‐emissive horizontal p‐distyrylbenzene (DSB) nanosheet (NS) arrays on 9,10‐dicyanoanthracene (DCA)‐dominated (DCA)1‐x(DSB)x doped nanowire (NW) backbone via a facile stepwise solution‐processed method. It is shown that the DSB NS arrays generate blue amplified spontaneous emission (ASE), whereas the backbone of the (DCA)1‐x(DSB)x displays intense yellow emission. Surprisingly, the blue ASE can effectively propagate in (DCA)1‐x(DSB)x backbone immunity to DCA absorption and realize polarization filtering of output ASE. The mechanism of the orthogonal polarization between blue‐ASE from branches and absorption of DCA molecules in the backbone is responsible for the efficient transport of higher‐energy photons in narrow‐gap emitters. This molecular orientation‐induced polarized‐light transport can serve to control light propagation and function as polarization filter in a single heterostructure. The research provides an interesting example for the exploration of novel all‐optical switch devices in photonic circuits. [ABSTRACT FROM AUTHOR]

Maxwell’s electrodynamics admits radial charge densities of the elementary organization with one vertex of the spherical symmetry. A multi-vertex distribution of sharply inhomogeneous charge densities can also be described by monistic field solutions to Maxwell’s equations–equalities. Coulomb–Lorentz forces are exerted locally to correlated electric densities in their volume organization with the fixed self-energy integral. The long-range Coulomb interaction between the dense peaks of the charged space continuum can be described quantitatively through bulk integrals of local tensions within observable bodies in favor of the monistic all-unity in the material space physics of Descartes and Russian cosmists.

Nanoparticles (NPs) have been widely utilized in vaccine design. Although numerous NPs have been explored, NPs with adjuvant effects on their own have rarely been reported. We produce a promising self-assembled NP by integrating the pentameric Escherichia coli heat-labile enterotoxin B subunit (LTB) (studied as a vaccine adjuvant) with a trimer-forming peptide. This fusion protein can self-assemble into the NP during expression, and polysaccharide antigens (OPS) are then loaded in vivo using glycosylation. We initially produced two Salmonella paratyphi A conjugate nanovaccines using two LTB subfamilies (LTIB and LTIIbB). After confirming their biosafety in mice, the data showed that both nanovaccines (NP(LTIB)-OPSSPA and NP(LTIIbB)-OPSSPA) elicited strong polysaccharide-specific antibody responses, and NP(LTIB)-OPS resulted in better protection. Furthermore, polysaccharides derived from Shigella or Klebsiella pneumoniae were loaded onto NP(LTIB) and NP(LTIIbB). The animal experimental results indicated that LTIB, as a pentamer module, exhibited excellent protection against lethal infections. This effect was also consistent with that of the reported cholera toxin B subunit (CTB) modular NP in all three models. For the first time, we prepared a novel promising self-assembled NP based on LTIB. In summary, these results indicated that the LTB-based nanocarriers have the potential for broad applications, further expanding the library of self-assembled nanocarriers.

Currently, ultrashort oligopeptides consisting of fewer than eight amino acids represent a cutting-edge frontier in materials science, particularly in the realm of hydrogel formation. By employing solid-phase synthesis with the Fmoc/tBu approach, a novel pentapeptide, FEYNF-NH2, was designed, inspired by a previously studied sequence chosen from hen egg-white lysozyme (FESNF-NH2). Qualitative peptide analysis was based on reverse-phase high performance liquid chromatography (RP-HPLC), while further purification was accomplished using solid-phase extraction (SPE). Exact molecular ion confirmation was achieved by matrix-assisted laser desorption–ionization mass spectrometry (MALDI-ToF MS) using two different matrices (HCCA and DHB). Additionally, the molecular ion of interest was subjected to tandem mass spectrometry (MS/MS) employing collision-induced dissociation (CID) to confirm the synthesized peptide structure. A combination of research techniques, including Fourier-transform infrared spectroscopy (FTIR), fluorescence analysis, transmission electron microscopy, polarized light microscopy, and Congo red staining assay, were carefully employed to glean valuable insights into the self-assembly phenomena and gelation process of the modified FEYNF-NH2 peptide. Furthermore, molecular docking simulations were conducted to deepen our understanding of the mechanisms underlying the pentapeptide’s supramolecular assembly formation and intermolecular interactions. Our study provides potential insights into amyloid research and proposes a novel peptide for advancements in materials science. In this regard, in silico studies were performed to explore the FEYNF peptide’s ability to form polyplexes.

Liposomes and other nanoparticles have been widely studied as innovative nanomaterials because of their unique properties. Pyridinium salts, on the basis of 1,4-dihydropyridine (1,4-DHP) core, have gained significant attention due to their self-assembling properties and DNA delivery activity. This study aimed to synthesize and characterize original N-benzyl substituted 1,4-dihydropyridines and evaluate the influence on structure modifications on compound physicochemical and self-assembling properties. Studies of monolayers composed of 1,4-DHP amphiphiles revealed that the mean molecular areas values were dependent on the compound structure. Therefore, the introduction of N-benzyl substituent to the 1,4-DHP ring enlarged the mean molecular area by almost half. All nanoparticle samples obtained by ethanol injection method possessed positive surface charge and average diameter of 395–2570 nm. The structure of the cationic head-group affects the size of the formed nanoparticles. The diameter of lipoplexes formed by 1,4-DHP amphiphiles and mRNA at nitrogen/phosphate (N/P) charge ratios of 1, 2, and 5 were in the range of 139–2959 nm and were related to the structure of compound and N/P charge ratio. The preliminary results indicated that more prospective combination are the lipoplexes formed by pyridinium moieties containing N-unsubstituted 1,4-DHP amphiphile 1 and pyridinium or substituted pyridinium moieties containing N-benzyl 1,4-DHP amphiphiles 5a–c at N/P charge ratio of 5, which would be good candidates for potential application in gene therapy. [ABSTRACT FROM AUTHOR]

We aimed to determine the coacervation properties of high‐molecular‐weight (HMW) tissue‐derived elastin (TDE) and to examine the potential use of TDE particles as a cosmetic biomaterial. TDE solutions were filtered and divided into three fractions (1–3) according to the molecular weight of the elastin. The turbidity of fraction 2, which contained a large portion (58%) of HMW elastin polypeptides (>100 kDa), was measured under several pH values (3.0–11.0) and NaCl concentrations (0–1000 mM) to examine its coacervation ability. HMW TDE exhibited coacervation under the physiological conditions (temperature, pH, and NaCl concentration) of the skin surface. We performed inclusion and release experiments using three model chemicals with different molecular weights and measured the size and zeta potential of the fraction 3 particles to investigate the suitability of HMW elastin polypeptides. Fraction 3, which contained a larger portion (64%) of HMW elastin polypeptides, displayed a strong coacervation property at a phase transition temperature of 19.8 ± 0.1°C. The inclusion ratio of the model chemical Biebrich Scarlet (BS) with a molecular weight of <600 was approximately 92.1 ± 0.7%. The release profiles of BS from the particles linearly increased and reached a plateau after 15 days. Moreover, the average size of the particles with BS was 474.2 ± 24.6 nm. The low‐molecular‐weight (LMW) elastin peptides have moisturizing and whitening functions for the skin. We concluded that TDE, as a mixture of HMW polypeptides and LMW peptides, can potentially serve as a multifunctional and effective cosmetic biomaterial. [ABSTRACT FROM AUTHOR]

Short and ultra‐short peptides have been recently envisioned as excellent building blocks for the formulation of hydrogels with appealing properties. Due to its simplicity and capability to gel under physiological conditions, Fmoc‐FF (Nα‐fluorenylmethoxycarbonyl‐diphenylalanine), remains one of the most studied low molecular‐weight hydrogelators. Since its first identification in 2006, a plethora of its analogues were synthetized and investigated for the fabrication of novel supramolecular materials. Here we report a description of the Fmoc‐FF analogues in which the aromatic Fmoc group is replaced with other substituents. These analogues are distinguished into five different classes including derivatives: i) customized with solid phase peptide synthesis protecting groups; ii) containing non‐aromatic groups, iii) containing aromatic groups, iv) derivatized with metal complexes and v) containing stimuli‐responsive groups. The morphological, mechanical, and functional effects caused by this modification on the resulting material are also pointed out. [ABSTRACT FROM AUTHOR]

Background: The clinical symptoms of invasive fungal infections (IFI) are nonspecific, and early clinical diagnosis is challenging, resulting in high mortality rates. This study reports the development of a novel aptamer-G-quadruplex/hemin self-assembling color system (AGSCS) based on (1 → 3)-β-D-glucans' detection for rapid, specific and visual diagnosis of IFI. Methods: We screened high affinity and specificity ssDNA aptamers binding to (1 → 3)-β-D-glucans, the main components of cell wall from Candida albicans via Systematic Evolution of Ligands by EXponential enrichment. Next, a comparison of diagnostic efficiency of AGSCS and the (1 → 3)-β-D-glucans assay ("G test") with regard to predicting IFI in 198 clinical serum samples was done. Results: Water-soluble (1 → 3)-β-D-glucans were successfully isolated from C. albicans ATCC 10,231 strain, and these low degree of polymerization glucans (< 1.7 kD) were targeted for aptamer screening with the complementary sequences of G-quadruplex. Six high affinity single stranded DNA aptamers (A1, A2, A3, A4, A5 and A6) were found. The linear detection range for (1 → 3)-β-D-glucans stretched from 1.6 pg/mL to 400 pg/mL on a microplate reader, and the detection limit was 3.125 pg/mL using naked eye observation. Using a microplate reader, the sensitivity and specificity of AGSCS for the diagnosis of IFI were 92.68% and 89.65%, respectively, which was higher than that of the G test. Conclusion: This newly developed visual diagnostic method for detecting IFI showed promising results and is expected to be developed as a point-of-care testing kit to enable quick and cost effective diagnosis of IFI in the future. [ABSTRACT FROM AUTHOR]

Advances in the number and type of available biomaterials have improved medical devices such as catheters, stents, pacemakers, prosthetic joints, and orthopedic devices. The introduction of a foreign material into the body comes with a risk of microbial colonization and subsequent infection. Infections of surgically implanted devices often lead to device failure, which leads to increased patient morbidity and mortality. The overuse and improper use of antimicrobials has led to an alarming rise and spread of drug-resistant infections. To overcome the problem of drug-resistant infections, novel antimicrobial biomaterials are increasingly being researched and developed. Hydrogels are a class of 3D biomaterials consisting of a hydrated polymer network with tunable functionality. As hydrogels are customizable, many different antimicrobial agents, such as inorganic molecules, metals, and antibiotics have been incorporated or tethered to them. Due to the increased prevalence of antibiotic resistance, antimicrobial peptides (AMPs) are being increasingly explored as alternative agents. AMP-tethered hydrogels are being increasingly examined for antimicrobial properties and practical applications, such as wound-healing. Here, we provide a recent update, from the last 5 years of innovations and discoveries made in the development of photopolymerizable, self-assembling, and AMP-releasing hydrogels. [ABSTRACT FROM AUTHOR]

The first line of treatment for most solid tumors is surgical resection of the primary tumor with adequate negative margins. Incomplete tumor resections with positive margins account for over 75% of local recurrences and the development of distant metastases. In cases of oral cavity squamous cell carcinoma (OSCC), the rate of successful tumor removal with adequate margins is just 50–75%. Advanced real‐time imaging methods that improve the detection of tumor margins can help improve success rates,overall safety, and reduce the cost. Fluorescence imaging in the second near‐infrared (NIR‐II) window has the potential to revolutionize the field due to its high spatial resolution, low background signal, and deep tissue penetration properties, but NIR‐II dyes with adequate in vivo performance and safety profiles are scarce. A novel NIR‐II fluorophore, XW‐03‐66, with a fluorescence quantum yield (QY) of 6.0% in aqueous media is reported. XW‐03‐66 self‐assembles into nanoparticles (≈80 nm) and has a systemic circulation half‐life (t1/2) of 11.3 h. In mouse models of human papillomavirus (HPV)+ and HPV‐ OSCC, XW‐03‐66 outperformed indocyanine green (ICG), a clinically available NIR dye, and enabled intraoperative NIR‐II image‐guided resection of the tumor and adjacent draining lymph node with negative margins. In vitro and in vivo toxicity assessments revealed minimal safety concerns for in vivo applications. [ABSTRACT FROM AUTHOR]

Octadecylazanediyl dipropionic acid (C18ADPA) is a zwitterionic amphiphile with a dendritic headgroup. C18ADPA self-assembles to lamellar networks, which encompasses water and forms a low-molecular-weight hydrogel (LMWG). In this study, we use the C18ADPA hydrogel as a drug carrier for the in vivo delivery of a copper salt for wound healing in a mouse model. A structural transition was observed based on cryo-scanning electron microscope (cryo-SEM) images after drug loading. The C18ADPA hydrogel, which had a layered structure, transformed into a self-assembled fibrillar network (SAFiN). The mechanical strength of the LMWG has always been an important issue in its applications. However, due to the structural transition, both the storage and loss moduli increased. In vivo tests showed that wound closure was faster after applying the hydrogel formulation compared with the Vaseline formulation. For the first time, we have also provided histological evidence of these effects on skin tissue. The hydrogel formulation exhibited clear advantages in regenerating tissue structure over traditional delivery formulations. [ABSTRACT FROM AUTHOR]

Self-assembling of organic molecules is of considerable interest seeing the development of functional biocompatible materials, micro- and nanoparticles, as well as the study of biomolecules structure and functioning. Here, we report on self-assembling of L-N-stearoyl glutamic acid and its dimethyl ester revealed by atomic force microscopy (AFM). The difference in size, shape, and behavior of the objects, detected on the surface, depending on their chemical nature, solvent, and AFM substrate, as well as deposition technique, is shown. Unwinding and re-assembling of the objects under the impact of the microscope probe were observed, indicating their quasi-stable chemical structure. [ABSTRACT FROM AUTHOR]

Weidong Zhao,1,2,&ast; Shaoyou Yang,3,&ast; Chunxiao Li,1,2 Feifei Li,1,2 Houjun Pang,3 Guangling Xu,1,2 Yuxin Wang,3 Mei Cong3 1Henan Key Laboratory of Immunology and Targeted Drugs, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, People’s Republic of China; 2Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, Xinxiang Medical University, Xinxiang, People’s Republic of China; 3School of Pharmacy, Xinxiang Medical University, Xinxiang, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Mei Cong, School of Pharmacy, Xinxiang Medical University, Xinxiang, 453003, People’s Republic of China, Tel +86 0373 3029879, Fax + 86 0373 3029879, Email 151051@xxmu.edu.cnPurpose: Gemcitabine is the first line and the gold standard drug for pancreatic cancer. However, the anticancer efficacy is severely limited by its instability and poor cellular uptake. To enhance the clinical efficacy of gemcitabine, we constructed a novel nanodrug delivery system based on amphiphilic dendrimers and aliphatic gemcitabine prodrug.Methods: An aliphatic gemcitabine prodrug and a small amphiphilic dendrimer were synthesized and characterized by high resolution mass spectrometry (HRMS) as well as nuclear magnetic resonance (NMR). Then the aliphatic gemcitabine prodrug was encapsulated into the small amphiphilic dendrimer by film dispersion method, resulting in a novel nanodrug delivery system. Subsequently, the size, morphology, drug loading, stability, drug release profiles, cell uptake, toxicity, the anticancer activity and in vivo distribution of the new developed gemcitabine delivery system were systematically evaluated by different technical methods, including transmission electron microscopy (TEM), dynamic light-scattering (DLS), ultraviolet spectrophotometer, flow cytometry, in vivo imaging system etc.Results: We developed a novel nanodrug delivery system of gemcitabine using amphiphilic dendrimer. This dendrimer-based gemcitabine nanoformulation reported here possess a high drug loading of 33%. With the features of small size, stable formulation and pH-responsive drug release, the obtained gemcitabine nanoformulation could effectively accumulate in tumor site and rapid uptake in cells. Finally, the gemcitabine nanoformulation displayed more potent anticancer activity compared to free gemcitabine both in vitro and in vivo. Moreover, the nanodrug displayed greatly reduced adverse effects and satisfactory biocompatibility.Conclusion: Benefiting the advantageous features of both amphiphilic dendrimers and nanotechnology-based drug delivery, this gemcitabine nanosystem constitutes a promising therapeutic candidate for pancreatic cancer treatment. This study also underlines the potential use of self-assembling amphiphilic dendrimer-based nanotechnology for improving drug efficacy as well as reducing drug toxicity.Graphical Abstract: Keywords: gemcitabine, amphiphilic dendrimer, self-assembling, pancreatic cancer, anticancer candidate

This work reports the preliminary results of the development of composite self-assembling membranes obtained by the combination of reduced graphene oxide (rGO) with commercial Degussa P25 titanium dioxide (TiO2). The purpose is to demonstrate the possibility of combining, in the same self-standing material, the capability to treat wastewater containing both inorganic and organic pollutants by exploiting the established ability of rGO to capture metal ions together with that of TiO2 to degrade organic substances. Moreover, this study also investigates the potential photocatalytic properties of tionite (TIO), to demonstrate the feasibility of replacing commercial TiO2 with such waste-derived TiO2-containing material, fulfilling a circular economy approach. Thus, rGO–TiO2 and rGO–TIO composite membranes, 1:1 by weight, were prepared and characterized by SEM-EDX, XRD, thermogravimetry, as well as by Raman and UV-Vis spectroscopies to verify the effective and homogeneous integration of the two components. Then, they were tested towards 3-mg L−1 aqueous synthetic solutions of Fe3+ and Cu2+ ions to evaluate their metal adsorption ability, with values of the order of 0.1–0.2 mmol gmembrane−1, comparable or even slightly higher than those of pristine rGO. Finally, the ability of the composites to degrade a common organic pesticide, i.e., Imidacloprid®, was assessed in preliminary photocatalysis experiments, in which maximum degradation efficiencies of 25% (after 3 h) for rGO–TiO2 and of 21% (after 1 h) for rGO–TIO were found. The result of tionite-containing membranes is particularly promising and worthy of further investigation, given that the anatase content of tionite is roughly 1/6 of the one in commercial TiO2. [ABSTRACT FROM AUTHOR]

Lacking high‐performance nonlinear optical (NLO) materials limits the applications to opto‐electronic devices. In this work, a strategy of self‐assembling driven by π‐π stacking is proposed to design high‐performance NLO materials. Here, the third‐order NLO responses of two carbon‐based fuller‐rylenes dimers (Fuller‐PMI and Fuller‐PDI) are theoretically studied. The results mainly highlight the following points: (1) these two dimers are in good thermodynamic and kinetic stability, and the interaction energies of Fuller‐PMI and Fuller‐PDI dimers have reached to −63.50 kcal/mol and −68.18 kcal/mol, respectively; (2) the ratios of the static second order hyperpolarizability (γiiiiFF, i∈{x, y, z}) between the dimer and the monomer are γxxxxFFdimerγxxxxFFmonomer = 5.5, γyyyyFFdimerγyyyyFFmonomer = 1.2 and γzzzzFFdimerγzzzzFFmonomer = 1.2 for Fuller‐PMI, γxxxxFFdimerγxxxxFFmonomer = 1.1, γyyyyFFdimerγyyyyFFmonomer =1.4 and γzzzzFFdimerγzzzzFFmonomer = 4.2 for Fuller‐PDI. These results demonstrate that the self‐assembling driven by π‐π stacking is an effective strategy for designing high‐performance NLO materials. [ABSTRACT FROM AUTHOR]

Maxwell's electrodynamics admits radial charge densities of the elementary organization with one vertex of the spherical symmetry. A multi-vertex distribution of sharply inhomogeneous charge densities can also be described by monistic field solutions to Maxwell's equations–equalities. Coulomb–Lorentz forces are exerted locally to correlated electric densities in their volume organization with the fixed self-energy integral. The long-range Coulomb interaction between the dense peaks of the charged space continuum can be described quantitatively through bulk integrals of local tensions within observable bodies in favor of the monistic all-unity in the material space physics of Descartes and Russian cosmists. [ABSTRACT FROM AUTHOR]

The calix[4]arene scaffold, blocked in the cone conformation through alkylation with long alkyl chains, and decorated at the upper rim with four guanidine or arginine units, effectively catalyzes the cleavage of the phosphodiester bond of DNA and RNA model compounds in water. An exhaustive kinetic investigation unequivocally points to the existence of spontaneous aggregation phenomena, driven by hydrophobic effect, occurring at different critical concentrations that depend on the identity of the compound. A pronounced superiority of the assembled structures compared with the monomers in solution was observed. Moreover, the catalytically active units, clustered on the macrocyclic tetrafunctional scaffold, were proved to efficiently cooperate in the catalytic mechanism and result in improved reaction rates compared to those of the monofunctional model compounds. The kinetic analysis is also integrated and corroborated with further experiments based on fluorescence spectroscopy and light scattering. The advantage of the supramolecular assemblies based on tetrafunctional calixarenes leads to believe that the active units can cooperate not only intramolecularly but also intermolecularly. The molecules in the aggregates can probably mold, flex and rearrange but, at the same time, keep an ordered structure that favors phosphodiester bond cleavage. This dynamic preorganization can allow the catalytic units to reach a better fitting with the substrates and perform a superior catalytic activity. [ABSTRACT FROM AUTHOR]

Peptides and their related compounds can self-assemble into diverse nanostructures of different shapes and sizes in response to various stimuli such as pH, temperature or ionic strength. Here we report the synthesis and characterization of a lysozyme derived pentapeptide and its ability to build well-defined fibrillar structures. Lysozyme FESNF peptide fragment was synthesized by solid phase peptide synthesis using the Fmoc/t-Bu strategy, purified by analytical high-performance liquid chromatography (HPLC) and its molecular weight was confirmed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI–MS). Spectroscopic features of this pentapeptide were investigated by UV-visible spectroscopy and fluorimetry showing the pattern of marginal phenylalanine residues within the peptide sequence. Self-assembling properties were determined using atomic force microscopy (AFM), aggregation index and thioflavin T assay (ThT). FESNF generating fibrillar structures observed by AFM and aggregation propensity were primarily influenced by pH conditions. Moreover, the experimental data were confirmed by molecular dynamics simulation studies. The obtained fibrils will be used next to explore their potential to act as support material for medical and cosmetic application. [ABSTRACT FROM AUTHOR]

With increasing heat accumulation in advanced modern electronic devices, dielectric materials with high thermal conductivity (λ) and excellent electrical insulation have attracted extensive attention in recent years. Inspired by mussel, hexagonal boron nitride (hBN) and graphene oxide (GO) are assembled to construct mhBN@GO hybrids with the assistance of poly(catechol-polyamine). Then, mhBN@GO hybrids are dispersed in carboxy nitrile rubber (XNBR) latex via emulsion coprecipitation to form elastomer composites with a high λ and satisfactory insulating properties. Thanks to the uniform dispersion of mhBN@GO hybrids, the continuous heat conduction pathways exert a significant effect on enhancing the λ and decreasing the interface thermal resistance of XNBR composites. In particular, the λ value of 30 vol% mhBN@GO/XNBR composite reaches 0.4348 W/(m·K), which is 2.7 times that of the neat XNBR (0.1623 W/(m·K)). Meanwhile, the insulating hBN platelets hinder the electron transfer between adjacent GO sheets, leading to satisfactory electrical insulation in XNBR composites, whose AC conductivity is as low as 10−10 S/cm below 100 Hz. This strategy opens up new prospects in the assembly of ceramic and carbonaceous fillers to prepare dielectric elastomer composites with high λ and satisfactory electrical insulation, making them promising for modern electrical systems. [ABSTRACT FROM AUTHOR]

Abstract The first line of treatment for most solid tumors is surgical resection of the primary tumor with adequate negative margins. Incomplete tumor resections with positive margins account for over 75% of local recurrences and the development of distant metastases. In cases of oral cavity squamous cell carcinoma (OSCC), the rate of successful tumor removal with adequate margins is just 50–75%. Advanced real‐time imaging methods that improve the detection of tumor margins can help improve success rates,overall safety, and reduce the cost. Fluorescence imaging in the second near‐infrared (NIR‐II) window has the potential to revolutionize the field due to its high spatial resolution, low background signal, and deep tissue penetration properties, but NIR‐II dyes with adequate in vivo performance and safety profiles are scarce. A novel NIR‐II fluorophore, XW‐03‐66, with a fluorescence quantum yield (QY) of 6.0% in aqueous media is reported. XW‐03‐66 self‐assembles into nanoparticles (≈80 nm) and has a systemic circulation half‐life (t1/2) of 11.3 h. In mouse models of human papillomavirus (HPV)+ and HPV‐ OSCC, XW‐03‐66 outperformed indocyanine green (ICG), a clinically available NIR dye, and enabled intraoperative NIR‐II image‐guided resection of the tumor and adjacent draining lymph node with negative margins. In vitro and in vivo toxicity assessments revealed minimal safety concerns for in vivo applications.

The pathogenic cascade of Alzheimer's disease (AD) characterized by amyloid-β protein accumulation is still poorly understood, partially owing to the limitations of relevant models without in vivo neural tissue microenvironment to recapitulate cell–cell interactions. To better mimic neural tissue microenvironment, three-dimensional (3D) core-shell AD model constructs containing human neural progenitor cells (NSCs) with 2% matrigel as core bioink and 2% alginate as shell bioink have been bioprinted by a co-axial bioprinter, with a suitable shell thickness for nutrient exchange and barrier-free cell interaction cores. These constructs exhibit cell self-clustering and -assembling properties and engineered reproducibility with long-term cell viability and self-renewal, and a higher differentiation level compared to 2D and 3D MIX models. The different effects of 3D bioprinted, 2D, and MIX microenvironments on the growth of NSCs are mainly related to biosynthesis of amino acids and glyoxylate and dicarboxylate metabolism on day 2 and ribosome, biosynthesis of amino acids and proteasome on day 14. Particularly, the model constructs demonstrated Aβ aggregation and higher expression of Aβ and tau isoform genes compared to 2D and MIX controls. AD model constructs will provide a promising strategy to facilitate the development of a 3D in vitro AD model for neurodegeneration research.

In this paper, the tailoring of superhydrophobic surfaces on AA6082 aluminum alloy by chemical etching in an HF/HCl solution, followed by silane self-assembling, was applied for enhanced corrosion protection in the marine field. In particular, different etching times were considered in order to optimize the treatment effect. The results indicate that all the prepared surfaces, after silanization, were characterized by superhydrophobic behavior with a contact angle higher than 150°. The contact and sliding angles strongly depend on the surface morphology at varying etching times. The optimum was observed with an etching time of 20 s, where a microscale coral-like structure coupled with a homogeneous and ordered pixel-like nanostructure was obtained on the aluminum surface showing a Cassie–Baxter superhydrophobic behavior with a water contact angle of 180° and a sliding angle equal to 0°. All superhydrophobic surfaces achieved an enhanced corrosion protection efficiency and impedance modulus up to two orders of magnitude higher than the as-received AA6082 in simulated seawater. [ABSTRACT FROM AUTHOR]

Protein-based materials intended as nanostructured drugs or drug carriers are progressively gaining interest in nanomedicine, since their structure, assembly and cellular interactivity can be tailored by recruiting functional domains. The main bottleneck in the development of deliverable protein materials is the lysosomal degradation that follows endosome maturation. This is especially disappointing in the case of receptor-targeted protein constructs, which, while being highly promising and in demand in precision medicines, enter cells via endosomal/lysosomal routes. In the search for suitable protein agents that might promote endosome escape, we have explored the translocation domain (TD) of the diphtheria toxin as a functional domain in CXCR4-targeted oligomeric nanoparticles designed for cancer therapies. The pharmacological interest of such protein materials could be largely enhanced by improving their proteolytic stability. The incorporation of TD into the building blocks enhances the amount of the material detected inside of exposed CXCR4+ cells up to around 25-fold, in absence of cytotoxicity. This rise cannot be accounted for by endosomal escape, since the lysosomal degradation of the new construct decreases only moderately. On the other hand, a significant loss in the specificity of the CXCR4-dependent cellular penetration indicates the unexpected role of the toxin segment as a cell-penetrating peptide in a dose-dependent and receptor-independent fashion. These data reveal that the diphtheria toxin TD displayed on receptor-targeted oligomeric nanoparticles partially abolishes the exquisite receptor specificity of the parental material and it induces nonspecific internalization in mammalian cells. [ABSTRACT FROM AUTHOR]

Achieving self‐assembling structures that exhibit emergent properties and functionalities is one of the holy grails in nanotechnology and holds great promise for a wide range of potential applications. Herein, a self‐assembled LuFeO3–(1/3)LuFe2O4–LuFeO3 heterostructure that consists of two model multiferroics, i.e., hexagonal LuFeO3 and rhombohedral LuFe2O4, is reported in single‐layer epitaxial LuFeO3 thin films. Atomic‐scale electron microscopy investigations reveal the spontaneous organization of ferroelectric polarization in each building block, which forms a series of polar configurations. Specifically, the charge and lattice of neighboring LuFeO3 and LuFe2O4 blocks are closely coupled with competing degrees of freedom. A combination of the quantitative analysis of atomically resolved images and spectroscopy with theoretical calculations determines how charge‐ordering‐induced polarization accommodates charge naturality across the interfaces to reduce the system energy and unravels the formation mechanism of this heterostructure. The results point to the possibilities of generation and control of multiferroic self‐assembled systems, which may provide a basis for engineering novel materials with emergent properties. [ABSTRACT FROM AUTHOR]