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Two-dimensional (2D) cell culture methods dominate the current research. However, the inherent responsiveness of cells to their native three-dimensional (3D) microenvironment necessitates a paradigm shift toward the development of advanced hydrogels that faithfully mimic the intricacies of the extracellular matrix (ECM) and enable continuous cell-ECM interactions. To address the constraints of traditional static hydrogel networks that impede effective cell-matrix and cell-cell interactions, and to tackle the inherent stability issues associated with dynamically cross-linked hydrogels, which have become a pressing concern. Herein, we present an interpenetrating polymer network (IPN) hydrogel (HA/Alg-RGD hydrogel) that combines a physically cross-linked network between alginate and calcium ions (Alg-Ca 2+ ) for the enhanced cell growth adaptability with a chemically cross-linked hyaluronic acid (HA) network to ensure macroscopic stability during cell culture. The incorporation of arginine-glycine-aspartic peptide modified alginate (Alg-RGD) further facilitates cell adhesion and improves the cell-hydrogel interaction. Notably, this IPN hydrogel demonstrates mechanical stability and enables cell spreading and growth within its structural framework. Leveraging the reversible characteristics of the ionically cross-linked Alg-Ca 2+ network within IPN hydrogels, we demonstrate the feasibility of the gelatin sacrificial solution for 3D printing purposes within the hydrogel matrix. Subsequent UV-induced covalent cross-linking enables the fabrication of vascularized microfluidic channels within the resulting construct. Our results demonstrate endothelial cell spreading and spontaneous cell sprouting within the hydrogel matrix, thus highlighting the efficacy of this IPN hydrogel system in facilitating 3D cell growth. Additionally, our study emphasizes the potential of 3D printed constructs as a promising approach for vascularization in tissue engineering. The importance of RGD peptides in promoting favorable cell-hydrogel scaffold interactions is also highlighted, emphasizing their critical role in optimizing biomaterial-cell interfaces.

Three novel copolymers based on zigzag naphthodithiophene (zNDT) with different aromatic rings as π bridges and different core side substitutions are designed and synthesized (PzNDT-T-1,3-bis(4-(2-ethylhexyl)-thiophen-2-yl)-5,7-bis(2-ethylhexyl)benzo[1,2-c:4,5-c']-dithiophene-4,8-dione (BDD), PzNDT-TT-BDD, and PzNDTP-T-BDD, respectively). The 2D conjugation structure and molecular planarity of the polymers can be effectively altered through the modification of conjugated side chains and π-bridges. These alterations contribute to the variation in energy levels, light absorption capacity, and morphology compatibility of the polymers. When blended with the nonfullerene acceptor (2,2'-[(4,4,9,9-tetrahexyl-4,9-dihydro-sindaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis[methylidyne(3-oxo-1H-indene-2,1(3H)-diylidene)]]bis-propanedinitrile) (IDIC), PzNDT-T-BDD exhibits the highest power conversion efficiency (PCE) of 9.72% among the three polymers. This result can be attributed to its superior crystallinity and more obvious face-on orientation in blending film. PzNDT-TT-BDD and PzNDTP-T-BDD present PCE values of 8.20% and 4.62%, respectively. The alteration of polymer structure, particularly the modification of conjugated side chains and π-bridges, is an effective strategy for designing NDT-based polymers with high photovoltaic performance and potential applications in fullerene-free solar cells., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

There is urgent demand of easily available and highly effective method to improve transgene performance of polymeric gene carriers at low consumption of delivery materials. We developed biocompatible multicomponent nanocomposites in which small quantities of cationic polythiophenes were engineered into the outer shell of polypeptide/DNA polyplexes without covalent linkages. We revealed the introduction of polythiophenes in small quantities led to multiple outcomes including modulation of polyplex size and zeta potential, increase in polyplex stability, promotion of endolysosome membrane disruption, light-induced generation of reactive oxygen species (ROS), and significant enhancement of gene delivery to tumor cells. The factors such as structural architectures, molecular weights, photosensitizing capability, and percentage composition of polythiophenes were investigated.

An IPC-imprinted (IPC is isoprocarb) poly(methacrylic acid)/SiO2 hybrid monolithic column was prepared and applied for the recognition of the template. The hybrid monolithic column was synthesized in a micropipette tip using methyltrimethoxysilane as the inorganic precursor, 3-(methacryloxy)propyltrimethoxysilane as the coupling agent, and ethylene glycol dimethacrylate as the cross-linker. The synthesis conditions, including the porogenic solvent, coupling agent, volume ratio of the inorganic alcoholysate and organic part, were optimized. The prepared monolithic column was characterized by SEM and FTIR spectroscopy. A simple, rapid, and sensitive method for the determination of IPC in rice using the imprinted monolithic column microextraction combined with HPLC was developed. Several parameters affecting the sample pretreatment were investigated, including the eluent, washing solution, and loading sample volume. The linearity of the calibration curve was observed in the range of 9.0-1000 μg/kg for IPC in rice with the correlation coefficient (r2) of 0.9983. The LOD was 3.0 μg/kg (S/N = 3). The assay gave recovery values ranging from 91 to 107%. The proposed method has been successfully applied for the selective extraction and sensitive determination of IPC in rice and a satisfactory result was obtained., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Main observation and conclusion: The on‐demand building copolymer structures, from sequence to architecture, is crucial in understanding the relation between polymer structure and property, meanwhile motivating the innovation of polymer hierarchy. However, the challenge is conspicuous for complicated polymer structures from inherently intricate polymerization. In this work, copolymers with tailored grafting density and distributions were achieved using successive latent monomer and grafting‐from strategies. The hydroxyl group functionalized furan/maleimide adduct (FMOH) was selected as the latent monomer for RAFT polymerization of an array of copolymers with tailored localization of hydroxyl group along the main chain. The hydroxyl group further initiated the ring opening polymerization (ROP) of L‐lactide or ε‐caprolactone, resulting in a library of multicomponent copolymers via grafting‐from strategy. The initiating efficiency reached to ~100% with variable molecular weight (21300—58600 Da) and narrow distributions (ÐM < 1.25), indicating that such graft copolymers possessed controlled density and distribution of side chains as its linear template. The investigation on thermal properties of the well‐defined graft copolymers implied that the precise tailoring over copolymer structures at the molecule level could lead to tunable chemical/physical properties. This work bridged polymer from sequence to architecture, unveiled a new method in creating graft copolymers with programmable structures and provided the insight into the structure/property relationship. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: The on‐demand building copolymer structures, from sequence to architecture, is crucial in understanding the relation between polymer structure and property, meanwhile motivating the innovation of polymer hierarchy. However, the challenge is conspicuous for complicated polymer structures from inherently intricate polymerization. In this work, copolymers with tailored grafting density and distributions were achieved using successive latent monomer and grafting‐from strategies. The hydroxyl group functionalized furan/maleimide adduct (FMOH) was selected as the latent monomer for RAFT polymerization of an array of copolymers with tailored localization of hydroxyl group along the main chain. The hydroxyl group further initiated the ring opening polymerization (ROP) of L‐lactide or ε‐caprolactone, resulting in a library of multicomponent copolymers via grafting‐from strategy. The initiating efficiency reached to ~100% with variable molecular weight (21300—58600 Da) and narrow distributions (ÐM < 1.25), indicating that such graft copolymers possessed controlled density and distribution of side chains as its linear template. The investigation on thermal properties of the well‐defined graft copolymers implied that the precise tailoring over copolymer structures at the molecule level could lead to tunable chemical/physical properties. This work bridged polymer from sequence to architecture, unveiled a new method in creating graft copolymers with programmable structures and provided the insight into the structure/property relationship. [ABSTRACT FROM AUTHOR]

2,5-Diformylfuran dioxime (DFFD), a rigid bio-based material, is a promising precursor for the manufacturing of advanced functional polymers. An acid autocatalytic oximation of bio-based 2,5-diformylfuran (DFF) initiated with 0.10 wt% HCl in 50 wt% aqueous hydroxylamine (AHA) at 30 °C yielded more than 99% DFFD within 5 min. The utilization efficiency of AHA and the conversion of DFF were 93% and 100%, respectively, through a stepwise AHA feeding strategy. The produced DFFD was easily separated at the kilogram scale by simple filtration, as DFFD was insoluble in water. During the reaction, the pH decreased continually from 6.0 to 2.0 along with the rapid generation of DFFD, which provided enough H+ to efficiently autocatalyse the oximation. Compared with hydroxylamine hydrochloride, AHA was much more efficient, and the generation of waste salts and wastewater decreased by 99.94% and 25%, respectively. Hence, we provide an efficient and clean DFFD production route, which is promising for the green utilization of bio-based furanic compounds. [ABSTRACT FROM AUTHOR]

The easily encodable and decodable digital polymer using dithiosuccinimide as sequence building block and sequencing indicator was proposed. • The easily encodable and decodable digital polymer was realized. • Dithiosuccinimide was used as the sequence building block for facile encoding information. • Dithiosuccinimide was used as the sequencing indicator was proposed for the ease of decoding information. Digital polymers with precise arrangements of units acting as the 0- or 1-bit, have shown bright promise for the data storage media. The easiness of encoding and decoding these polymers is essential when putting them into practical applications. Herein, the concept of utilizing sequence building block and sequencing indicator to generate easily encodable and decodable digital polymers is proposed. With the thiol-maleimide Michael coupling for digital chain growth, the dithiosuccinimide (DTS) motifs generated from the succinimide thioether linkages are used as the sequence building block. The DTS can be equipped with different groups, thus greatly enabling the modular encoding process. Importantly, the tandem mass spectrometry (MS/MS) results unveil the relatively abundant DTS-induced MS signal, which facilitates the decoding process with DTS acting as the sequencing indicator. The synergetic MS/MS induced cleavages of the two C S bonds on DTS are responsible for the relatively abundant MS signal. Finally, the work exemplifies the quantitatively decoding of a digital polymer with DTS as the sequence building block and sequencing indicator. This study demonstrates the concept of sequence building block and sequencing indicator, which advances the digital polymers for practical applications. [ABSTRACT FROM AUTHOR]

The morphology features of polymer/small molecule/fullerene ternary organic solar cells are investigated. For the first time, simultaneously enhanced face‐on molecular packing for both polymer and small‐molecule donor materials is observed. This optimized morphology yields an enhanced performance at 40% small‐molecule composition. [ABSTRACT FROM AUTHOR]

We have designed and tested a new way to selectively deliver HPMA polymer-coated adenovirus type 5 (Ad5) particles into matrix metalloproteinase (MMP)-overexpressing tumor cells. An activatable cell penetrating peptide (ACPP) was designed and attached to the reactive 4-nitrophenoxy groups of HPMA polymers by the C-terminal amino acid (asparagine, N). ACPPs are activatable cell penetrating peptides (CPPs) with a linker between polycationic and polyanionic domains, and MMP-mediated cleavage releases the CPP portion and its attached cargo to enable cell entry. Our data indicate that the transport of these HPMA polymer conjugates by a single ACPP molecule to the cytoplasm occurs via a nonendocytotic and concentration-independent process. The uptake was observed to finish within 20 minutes by inverted fluorescence microscopy. In contrast, HPMA polymer-coated Ad5 without ACPPs was internalized solely by endocytosis. The optimal formulation was not affected by the presence of Ad5 neutralizing antibodies during transduction, and ACPP/polymer-coated Ad5 also retained high targeting capability to several MMP-overexpressing tumor cell types. For the first time, ACPP-mediated cytoplasmic delivery of polymer-bound Ad5 to MMP-overexpressing tumor cells was demonstrated. These findings are significant, as they demonstrate the use of a polymer-based system for the targeted delivery into MMP-overexpressing solid tumors and highlight how to overcome major cellular obstacles to achieve intracellular macromolecular delivery. [ABSTRACT FROM AUTHOR]

Compared with nonfullerene‐based polymer solar cells, all‐small‐molecule solar cells normally show low power conversion efficiencies (PCEs) due to their low fill factors (FFs). Molecular stacking orientation and phase separation are the main factors affecting the performance of all‐small‐molecule solar cells. In this work, two liquid‐crystalline small‐molecule donors are designed and synthesized and a novel nonfullerene acceptor with good crystallinity developed. Owing to the face‐on orientation of the component molecules and appropriate phase separation in the active layer, a high FF of over 70% and a PCE of 10.7% are obtained from the resulting solar cells; these values are among the best obtained thus far for all‐small‐molecule solar cells. The high FF reported here is significant for a further design of high‐performance all‐small‐molecule solar cells. The combination of a liquid‐crystalline small‐molecule donor and a nonfullerene acceptor with good crystallinity provides appropriate phase separation and molecular stacking orientation for all‐small‐molecule solar cells. The fill factors and power conversion efficiencies (PCEs) are obviously improved in the proposed systems, and the maximum PCE reaches 10.7%. The results are significant for the construction and development of all‐small‐molecule solar cells. [ABSTRACT FROM AUTHOR]

Summary Many DNA and RNA regulatory proteins contain polypeptide domains that are unstructured when analyzed in cell lysates. These domains are typified by an over-representation of a limited number of amino acids and have been termed prion-like, intrinsically disordered or low-complexity (LC) domains. When incubated at high concentration, certain of these LC domains polymerize into labile, amyloid-like fibers. Here, we report methods allowing the generation of a molecular footprint of the polymeric state of the LC domain of hnRNPA2. By deploying this footprinting technique to probe the structure of the native hnRNPA2 protein present in isolated nuclei, we offer evidence that its LC domain exists in a similar conformation as that described for recombinant polymers of the protein. These observations favor biologic utility to the polymerization of LC domains in the pathway of information transfer from gene to message to protein. [ABSTRACT FROM AUTHOR]