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Aiming to circumvent the pre-defined obstacles in the journey of gene transportation, we attempt to compile a number of functional components into a tandem tri-copolymeric material. Herein, a β-cyclodextrin-functionalized poly(glycerol methacrylate) (PG) segment and a quaternary amine-functionalized poly[(2-acryloyl)-ethyl-(p-boronic acid pinacol ester benzyl)diethylammonium bromide] (BP) segment are attached to complex DNA to formulate a nanoscaled delivery system based on electrostatic interactions. The formulated polyplex is strengthened by a hydrophobic poly[2-(5,5-dimethyl-1,3-dioxan-2-yloxy)ethyl acrylate] (PDM) segment, affording improved complex stability. To retrieve the polyplex from entrapment by acidic and digestive endo/lysosomes, light-stimulated ROS-producing 4,4'-(1,2-diphenylethene-1,2-diyl)bis(1,4-phenylene)diboronic acid (TPE) is installed in the cavities of cyclodextrin. Upon light irradiation, TPE is triggered to produce abundant ROS, not only committing disruption of the endo/lysosome membrane for polyplex escape from the entrapment but also inducing the transformation of the positively charged BP to become negatively charged. This charge conversion behavior, together with the transformation of PDM to be hydrophilic and responsive to an acidic endosome pH gradient (pH 5.0) is envisioned to induce the dissociation of the electrostatically-assembled polyplex, thereby facilitating the release of the DNA payload for the subsequent transcription machinery. This strategically-tailored and easily synthesized tandem tri-copolymer exhibits excellent gene expression activity and provides a facile response to endogenous and exogenous stimuli for active gene expression.

Ternary copolymerization is a cost‐effective and time‐saving approach to improve device performance and batch stability of polymer donors. However, the structure of the ternary polymer donor obtained by the traditional one‐pot polymerization is vague due to the different monomer reaction order, which has a great influence on the absorption, crystallization, molecular stacking, and device performance. Therefore, it is necessary to obtain terpolymers with definite structures, and systematically study the differences in device properties of polymers with different sequence structures. Herein, three terpolymers D1, D2, and D3 are developed. Random copolymer D3 is obtained via the traditional one‐pot method while alternating copolymer donor D1 and block copolymer D2 are synthesized by stepwise polymerization. Because the block copolymer D2 possess periodic sequence distribution and retains the excellent properties of the two polymer matrix very well, the D2‐based device shows enhanced tightened π‐face‐on molecular stacking, distinguished efficient exciton dissociation, and decreased energy loss. As a result, the D2:L8‐BO‐based polymer solar cells achieve one of a record power conversion efficiency of 19.03%. The work demonstrates changing the sequence structure of the polymers to synthesize well‐defined structures polymer donors not only maintains the features of polymer matrix, but also combines the advantages of ternary copolymerization. [ABSTRACT FROM AUTHOR]

Ternary polymerization are demonstrated as a feasible and successful method of optimizing absorption, energy level, and crystallinity by maintaining the excellent properties of a polymer matrix. However, the third unit inevitably interrupts the periodic sequence distribution of the ordering packing of conjugated backbones, and thus balancing the trade‐off between the advantages of the third component and the disruption caused by the nonperiodic sequence distribution remains a great challenge. Herein, two terpolymer donors L1 and L2 are developed by introducing diethyl‐5,5′"‐dibromo‐4,4′"‐bis(2‐ethylhexyl)‐[2,2′:5′,2′'‐terthiophene]‐3′,4′‐dicarboxylate (DDT) unit as the third component. Owing to the electron‐deficient ability and S···O non‐covalent intramolecular interactions of DDT, terpolymers L1 and L2 displays deeper energy levels, enhanced molecular rigidity, and planarity than PM6. After blending with L8‐BO, the L1‐based polymer solar cells exhibit well miscibility with L8‐BO, leading to a more well‐defined nanofibrous morphology, face‐on orientation, and a slight energy loss in the blend films. As a result, the optimized L1:L8‐BO‐based device achieves a record power conversion efficiency (PCE) as high as 18.75%. This work provides a feasible strategy to develop high‐performance polymer donors via utilizing S···O non‐covalent intramolecular interactions to improve the planarity of polymer donors. [ABSTRACT FROM AUTHOR]

Novel terpolymers were developed with ester group incorporation (BDT-2EST). DM1 with 5% BDT-2EST possesses suitable crystallinity and miscibility matching with Y6 acceptor to offer an excellent power conversation efficiency up to 17.21%. Moreover, the intertwined random features in DM1 offer robust photovoltaic performances with a broad molecular weight tolerance. [ABSTRACT FROM AUTHOR]

A channel suspension method to fabricate high performance graphene field effect transistors (GFET) is presented in this paper. The balance is reached between gate efficiency and carrier mobility. A GFET with 15 μm × 15 μm gate dimension achieves a high normalized transconductance. Peak intrinsic carrier mobility is extracted to be 44 600 cm2v-1s-1. Suspension of the graphene channel is confirmed by AFM, SEM, and gate capacitance measurements. Unlike traditional substrate supported GFET, the proposed suspended-channel structure suppresses the influence of extrinsic scatterings and, meanwhile, maintains a certain gate controllability. [ABSTRACT FROM AUTHOR]