In this paper, we present a computational reverse-engineering analysis for scattering experiments (CREASE) based on genetic algorithms and molecular simulation to analyze the structure within self-assembled amphiphilic polymer solutions. For a given input comprised of scattering intensity profiles and information about the amphiphilic polymers in solution, CREASE outputs the structure of the self-assembled micelles (e.g., core and corona diameters, aggregation number) as well as the conformations of the amphiphilic polymer chains in the micelle (e.g., blocks’ radii of gyration, chain radii of gyration, monomer concentration profiles). First, we demonstrate CREASE’s ability to reverse-engineer self-assembled nanostructures for scattering profiles obtained from molecular simulations (or in silico experiments) of generic coarse-grained bead–spring polymer chains in an implicit solvent. We then present CREASE’s outputs for scattering profiles obtained from small-angle neutron scattering (SANS) experiments of poly­(d-glucose carbonate) block copolymers in solution that exhibit assembly into spherical nanoparticles. The success of this method is demonstrated by its ability to replicate, quantitatively, the results from in silico experiments and by the agreement in micelle core and corona sizes obtained from microscopy of the in vitro solutions. The primary strength of CREASE is its ability to analyze scattering profiles without an off-the-shelf scattering model and the ability to provide chain and monomer level structural information that is otherwise difficult to obtain from scattering and microscopy alone.

Although nanomedicines have been pursued for nearly 20 years, fundamental chemical strategies that seek to optimize both the drug and drug carrier together in a concerted effort remain uncommon yet may be powerful. In this work, two block polymers and one dimeric prodrug molecule were designed to be coassembled into degradable, functional nanocarriers, where the chemistry of each component was defined to accomplish important tasks. The result is a poly(ethylene glycol) (PEG)-protected redox-responsive dimeric paclitaxel (diPTX)-loaded cationic poly(d-glucose carbonate) micelle (diPTX@CPGC). These nanostructures showed tunable sizes and surface charges and displayed controlled PTX drug release profiles in the presence of reducing agents, such as glutathione (GSH) and dithiothreitol (DTT), thereby resulting in significant selectivity for killing cancer cells over healthy cells. Compared to free PTX and diPTX, diPTX@CPGC exhibited improved tumor penetration and significant inhibition of tumor cell growth toward osteosarcoma (OS) lung metastases with minimal side effects both in vitro and in vivo, indicating the promise of diPTX@CPGC as optimized anticancer therapeutic agents for treatment of OS lung metastases.

Fundamental studies that gain an understanding of the tunability of physical properties of natural product-based polymers are vital for optimizing their performance in extensive applications. Variation of glass transition temperature (T g) was studied as a function of the side chain structure and molar mass for linear poly­(glucose carbonate)­s. A remarkable range of T g values, from 38 to 125 °C, was accomplished with six different alkyloxycarbonyl side chains. The impact of molar mass on T g was investigated for two series of polymers and discrete oligomers synthesized and fractionated with precise control over the degrees of polymerization. The T g was found to be greatly influenced by a synergistic effect of the flexibility and bulkiness of the repeating unit side chain, as well as the chain end relative free volume. This work represents an important advance in the development of glucose-based polycarbonates, as materials that possess high degrees of functionalizability to be capable of exhibiting diversified physicochemical and thermal properties by simple side chain modification.

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The electrochemical reduction of CO 2 into fuels and valuable chemicals represents an appealing approach to alleviate energy crisis and global warming. Due to its sluggish reaction kinetics and the lack of suitable electrocatalysts it remains a major challenge. In this work, we report a facile synthetic approach to engineer a polymeric cobalt phthalocyanine network with rich defects for significantly enhanced electrocatalytic activity for CO 2 reduction. The successful defect engineering not only promotes the formation of a stronger binding surface towards CO 2 , but also simultaneously turns the electronic character of the resulting cobalt phthalocyanine framework. As a result, the new defective polymer exhibits highly selective catalysis of aqueous reduction of CO 2 into CO with a large faradaic efficiency of ca. 97 %, low applied overpotential of 490 mV (versus a reversible hydrogen electrode) and long-term stability. We anticipated that this new strategy could inspire the discovery of new organic frameworks for efficient CO 2 reduction, such as those (defective MOFs, COFs etc.), evidently advancing the development of catalysts for the CO 2 reduction reaction.The environmental concerns of the increasing CO 2 concentration in the atmospheric and global energy demands has inspired an extensive search of new technologies that enable an efficient and sustainable reductive conversion of CO 2 to fuels and commodity chemicals. [1] One promising solution is the electrochemical CO 2 reduction as it benefits from using water as the reaction medium; however, it remains a great challenge to achieve efficient reduction of CO 2 at low applied overpotentials mainly due to its sluggish reaction kinetics and competitive deduction of water itself to hydrogen. Huge efforts have therefore been devoted to the rational design and synthesis of new materials to overcome this obstacle. [2] Among them, polymeric organic networks (PONs) built from transition metal macrocycles, for example, metalloporphyrin-linked metal organic frameworks (MOFs) and covalent organic frameworks (COFs), offer attributes that make them potentially compelling choices for the electrocatalytic CO 2 reduction reaction (CO 2 RR). [3] Notably, transition metal macrocycles embedded within the polymeric frameworks can direct the catalysis along selected multielectron pathways, and thereby affording highly selective conversion of CO 2 to desired products. [3a,4] Further optimization of these active centers by turning their electronic features, so as to boost the CO 2 RR performance, in terms of activity and selectivity, has recently attracted significant interests. [3d] However, direct modulation of these macrocycle moieties using conventional organic techniques is challenging due to intrinsic synthetic difficulties. [3d] As such, the search of novel strategies that enables an efficient and straightforward functionalization is of great interest, importance, and urgency.Here, we report a facile synthetic approach to engineer a cobalt (Co) phthalocyanine-linked p...