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Over the past decade, the field of polymer-oligonucleotide nanomaterials has flourished because of the development of synthetic techniques, particularly living polymerization technologies, which provide access to polymers with well-defined architectures, precise molecular weights, and terminal or side-chain functionalities. Various "living" polymerization methods have empowered chemists with the ability to prepare functional polymer-oligonucleotide conjugates yielding a library of architectures, including linear diblock, comb, star, hyperbranched star, and gel morphologies. Since oligonucleotides are hydrophilic and synthetic polymers can be tailored with hydrophobicity, these amphiphilic polymer-oligonucleotide conjugates are capable of self-assembling into nanostructures with different shapes, leading to many high-value-added biomedical applications, such as drug delivery systems, gene regulation, and 3D-bioprinting. This review aims to highlight the main living polymerization approaches to polymer-oligonucleotide conjugates, including ring-opening metathesis polymerization, atom transfer radical polymerization (ATRP), reversible addition-fragmentation transfer polymerization (RAFT), and ring-opening polymerization of cyclic esters and N -carboxyanhydride. The self-assembly properties and resulting applications of polymer-DNA hybrid materials are highlighted as well.

Background: Itaconic acid (IA) is a versatile platform chemical widely used for the synthesis of various polymers and current methods for IA production based on Aspergillus terreus fermentation are limited in terms of process efficiency and productivity. To construct more efficient IA production strains, A. niger was used as a chassis for engineering IA production by assembling the key components of IA biosynthesis pathways from both A. terreus and Ustilago maydis. Results: Recombinant A. niger S1596 overexpressing the A. terreus IA biosynthesis genes cadA, mttA, mfsA produced IA of 4.32 g/L, while A. niger S2120 overexpressing the U. maydis IA gene cluster adi1, tad1, mtt1, itp1 achieved IA of 3.02 g/L. Integration of the two IA production pathways led to the construction of A. niger S2083 with IA titers of 5.58 g/L. Increasing cadA copy number in strain S2083 created strain S2209 with titers of 7.99 g/L and deleting ictA to block IA degradation in S2209 created strain S2288 with IA titers of 8.70 g/L. Overexpressing acoA to enhance the supply of IA precursor in strain S2288 generated strain S2444 with IA titers of 9.08 g/L in shake flask. Conclusion: Recombinant A. niger overexpressing the U. maydis IA biosynthesis pathway was capable of IA accumulation. Combined expression of the two IA biosynthesis pathways from A. terreus and U. maydis in A. niger resulted in much higher IA titers. Furthermore, increasing cadA copy number, deleting ictA to block IA degradation and overexpressing acoA to enhance IA precursor supply all showed beneficial effects on IA accumulation. [ABSTRACT FROM AUTHOR]

The structure of CaO–Al2O3–B2O3–BaO glassy slags with varying mass ratio of BaO to CaO has been investigated by Raman spectroscopy, 11B and 27Al magic angle spinning nuclear magnetic resonance (MAS‐NMR) spectroscopy and atomic pair distribution function (PDF). 11B MAS‐NMR spectra reveal the dominant coordination of boron as trigonal. Both simulations on 11B MAS‐NMR spectra and Raman spectroscopy indicate the presence of orthoborate as the primary borate group with a few borate groups with one bridging oxygen and minor four‐coordinated boron sites. 27Al MAS‐NMR and PDF show the Al coordination as tetrahedral. Raman spectral study shows that the transverse vibration of AlIV–O–AlIV and AlIV–O–BIII, stretching vibration of aluminate structural units and vibration of orthoborate and pyroborate structural groups. A broader distribution of Al–O bond lengths in PDF also supports the enhanced network connectivity. Viscosity measurements show the increase in viscosity of molten slags with increasing mass ratio of BaO to CaO, which further attributes to the enhanced degree of polymerization of the aluminate network. [ABSTRACT FROM AUTHOR]

Melanosomes in nature have diverse morphologies, including spheres, rods, and platelets. By contrast, shapes of synthetic melanins have been almost entirely limited to spherical nanoparticles with few exceptions produced by complex templated synthetic methods. Here, we report a non‐templated method to access synthetic melanins with a variety of architectures including spheres, sheets, and platelets. Three 1,8‐dihydroxynaphthalene dimers (4‐4′, 2‐4′ and 2‐2′) were used as self‐assembling synthons. These dimers pack to form well‐defined structures of varying morphologies depending on the isomer. Specifically, distinctive ellipsoidal platelets can be obtained using 4‐4′ dimers. Solid‐state polymerization of the preorganized dimers generates polymeric synthetic melanins while maintaining the initial particle morphologies. This work provides a new route to anisotropic synthetic melanins, where the building blocks are preorganized into specific shapes, followed by solid‐state polymerization. [ABSTRACT FROM AUTHOR]

Herein, we report the photoinitiated polymerization‐induced self‐assembly (photo‐PISA) of spherical micelles consisting of proapoptotic peptide–polymer amphiphiles. The one‐pot synthetic approach yielded micellar nanoparticles at high concentrations and at scale (150 mg mL−1) with tunable peptide loadings up to 48 wt. %. The size of the micellar nanoparticles was tuned by varying the lengths of hydrophobic and hydrophilic building blocks. Critically, the peptide‐functionalized nanoparticles imbued the proapoptotic "KLA" peptides (amino acid sequence: KLAKLAKKLAKLAK) with two key properties otherwise not inherent to the sequence: 1) proteolytic resistance compared to the oligopeptide alone; 2) significantly enhanced cell uptake by multivalent display of KLA peptide brushes. The result was demonstrated improved apoptosis efficiency in HeLa cells. These results highlight the potential of photo‐PISA in the large‐scale synthesis of functional, proteolytically resistant peptide–polymer conjugates for intracellular delivery. [ABSTRACT FROM AUTHOR]

A novel approach was developed to prepare molecularly imprinted polymer (MIP) composites on filter paper and with the subsequent determination of sulfamethoxazole in food samples. Hemoglobin was firstly encapsulated in a metal-organic framework to improve its stability and catalytic performance. This mixture was modified with an initiator and immobilized in the paper to prepare the MIP using electrochemically mediated atom transfer radical polymerization. This composite exhibited excellent adsorption capacity (60.1 mg g−1) and rapid kinetics, which were better than those of previously reported MIPs. Using the optimized conditions, this MIP composite directly extracted the sulfamethoxazole from complex food samples and was placed on the surface of a screen-printed electrode to quantify sulfamethoxazole with a detection limit of 0.7 ng mL−1. Sulfamethoxazole recoveries ranged from 99.4 to 103.7% and the results were in good agreement with those obtained by a liquid chromatography – mass spectrometry (LC-MS) method (r = 0.992). This approach may also be applied for the determination of other target molecules. [ABSTRACT FROM AUTHOR]

Harnessing metal‐free photoinduced reversible‐deactivation radical polymerization (photo‐RDRP) in organic and aqueous phases, we report a synthetic approach to enzyme‐responsive and pro‐apoptotic peptide brush polymers. Thermolysin‐responsive peptide‐based polymeric amphiphiles assembled into spherical micellar nanoparticles that undergo a morphology transition to worm‐like micelles upon enzyme‐triggered cleavage of coronal peptide sidechains. Moreover, pro‐apoptotic polypeptide brushes show enhanced cell uptake over individual peptide chains of the same sequence, resulting in a significant increase in cytotoxicity to cancer cells. Critically, increased grafting density of pro‐apoptotic peptides on brush polymers correlates with increased uptake efficiency and concurrently, cytotoxicity. The mild synthetic conditions afforded by photo‐RDRP, make it possible to access well‐defined peptide‐based polymer bioconjugate structures with tunable bioactivity. [ABSTRACT FROM AUTHOR]

The conformational properties of a polymer chain adsorbed on an attractive spherical nanoparticle are studied by using Monte Carlo simulations. The adsorption degree of polymer is described by the number of adsorbed monomers n and the length of adsorbed block l . The configuration of the adsorbed polymer on a nanoparticle is described by trains, loops, and tails. We find three different structures for the adsorbed polymer: a structure with trains, loops, and tails at small polymer-nanoparticle interaction strength ε , a structure with a train and a tail at large ε , and a structure with trains and loops at large n . In addition, we find that the mean number of adsorbed monomers < n > is scaled with l as < n > ~ l at ε ≥ 1, and the exponent α increases with ε . Our results indicate that both the adsorption degree and the configuration of the adsorbed polymer are dependent on the polymer-nanoparticle interaction strength, the number of adsorbed monomers, and the length of adsorbed block. [ABSTRACT FROM AUTHOR]

Allomelanin, anisotropy, DHN melanin, melanin, solid-state polymerization Keywords: allomelanin; anisotropy; DHN melanin; melanin; solid-state polymerization EN allomelanin anisotropy DHN melanin melanin solid-state polymerization 17361 17361 1 07/28/21 20210802 NES 210802 B Anisotrope synthetische Melanine b wurden durch Festkörperpolymerisation hergestellt, wie Nathan C. Gianneschi et al. in ihrem Forschungsartikel auf S. 17605 berichten. Titelbild: Anisotropic Synthetic Allomelanin Materials via Solid-State Polymerization of Self-Assembled 1,8-Dihydroxynaphthalene Dimers (Angew. [Extracted from the article]

Keywords: allomelanin; anisotropy; DHN melanin; melanin; solid-state polymerization EN allomelanin anisotropy DHN melanin melanin solid-state polymerization 17221 17221 1 07/28/21 20210802 NES 210802 B Anisotropic synthetic melanins b have been generated by solid-state polymerization, as reported by Nathan C. Gianneschi et al. in their Research Article on page 17464. Ellipsoidal platelets of melanin, found to date only in biology, were obtained through pre-organizing the 4-4' dihydroxynaphthalene dimer as the building block, followed by solid-state oxidative polymerization to give polymeric melanin materials without changing their overall morphology. Ellipsoidal platelets of melanin, found to date only in biology, were obtained through pre-organizing the 4-4' dihydroxynaphthalene dimer as the building block, followed by solid-state oxidative polymerization to give polymeric melanin materials without changing their overall morphology. [Extracted from the article]

Rücktitelbild: Bioactive Peptide Brush Polymers via Photoinduced Reversible-Deactivation Radical Polymerization (Angew. B Peptid-Bürstenpolymere b wurden durch photoinduzierte radikalische Polymerisation unter reversibler Deaktivierung (photo-RDRP) hergestellt, wie N. C. Gianneschi et al. in ihrem Forschungsartikel auf S. 17520 berichten. Die Autoren schlagen sie als neue Klasse von "Polypeptiden" vor, bei denen die Peptide entlang eines synthetischen Polymerrückgrats organisiert sind. [Extracted from the article]

Abstract: >300°C fraction obtained by distillation of heavy tar of low temperature coal tar was reacted with paraformaldehyde. After reaction, toluene soluble (TS-tar) and toluene insoluble (TIS-tar) fractions were collected. Their structures were confirmed by gas chromatography–mass spectroscopy (GC–MS), gel permeation chromatography (GPC) and Fourier transformed infrared (FTIR). The degradations under nitrogen atmosphere of >300°C fraction and TIS-tar were investigated by thermogravimetric analyzer coupled with Fourier transform infrared spectroscopy (TG-FTIR). Based on the above analyses, polymers were generated and the carbonization yields were increased by polymerization reaction. The degradation process of TIS-tar was divided into two stages, 118–248°C and 248–700°C. In the pyrolysis process of >300°C fraction, CO has no significant absorbency for infrared at 2060–2240cm−1, but there are obvious absorption peaks in TIS-tar. Polymerization reaction of paraformaldehyde and compounds with carboxyl, short-chain fatty and ester group in >300°C fraction generates polymers and fixes these compounds. [Copyright &y& Elsevier]

Porous fly ash-based geopolymer material was produced using fly ash and sodium water glass as original material and H 2 O 2 as foaming agent. The changes caused by the geopolymerization and decomposition of H 2 O 2 on the properties of the final products were investigated by applying curing on geopolymer mortars with different amounts of sodium water glass (60, 80 and 100 g) and H 2 O 2 (4, 6 and 8 g) added at various curing temperatures. The samples were cured at two different temperatures (55 and 85 °C). Physical properties such as porosity, density and thermal conductivity and mechanical property were determined from the completely dried samples. As a result, this study confirmed that the amount of sodium water glass, H 2 O 2 and curing temperature had effects on properties of the samples. Given the compressive strength obtained and the environmental and economic effect, the optimal thermal curing temperature and the amount of sodium water glass and H 2 O 2 were 55 °C, 80 g and 6 g, respectively. Sample synthesized at this condition had porosity of 79.9%, thermal conductivity of 0.0744 W/m K and compressive strength of 0.82 MPa. Therefore, it shows promise as thermal insulation material in some situations. [ABSTRACT FROM AUTHOR]