Hierarchical block copolymer self-assembly is used to produce "polyplex-in-hydrophobic-core" (PIHC) micelles for gene delivery. The unique PIHC micelle structure provides nuclease protection and controlled release by embedding nucleic acids in the micelle core surrounded by condensed hydrophobic polymer chains. PIHC micelles are generated through a simple, two-step process using commercially available polymers: (1) electrostatic binding between the nucleic acid cargo and poly(ε-caprolactone)block-poly(2-vinyl pyridine) (PCL-b-P2VP) (SA1), followed by (2) microprecipitation of the polyplex with poly(ε-caprolactone)block-poly(ethylene glycol) (SA2). The resulting vectors possess poly(ethylene glycol) (PEG) coronae and nucleic acid−P2VP polyplexes embedded within condensed PCL hydrophobic cores. Using a two-phase microfluidic reactor for the SA2 step, we produce mainly spherical PIHC micelles with ∼30 nm PCL cores and ∼15 nm PEG shells. Plasmids encapsulated in PIHC micelles show resistance to DNase I degradation compared to plasmids located outside the micelle cores. PIHC micelles containing pUC18 show enhanced transformation efficiencies in competent Escherichia coli with a linear time dependence over 8 h associated with slow plasmid release via hydrolytic degradation of PCL cores. Finally, we show that PIHC micelles are readily taken into the cytosol of MDA-MB-231 (human breast cancer) cells.

The development of long‐lived electrochemical energy storage systems based on renewable materials is integral for the transition toward a more sustainable society. Supercapacitors have garnered considerable interest given their impressive cycling performance, low cost, and safety. Here, the first example of a chiral nematic activated carbon aerogel is shown. Specifically, supercapacitor materials are developed based on cellulose, a non‐toxic and biodegradable material. The chiral nematic structure of cellulose nanocrystals (CNCs) is harnessed to obtain free‐standing hierarchically ordered activated carbon aerogels. To impart multifunctionality, iron‐ and cobalt‐oxide nanoparticles are incorporated within the CNC matrix. The hierarchical structure remains intact even at nanoparticle concentrations of ≈70 wt%. The aerogels are highly porous, with specific surface areas up to 820 m2 g−1. A maximum magnetization of 17.8 ± 0.1 emu g−1 with superparamagnetic behavior is obtained, providing a base for actuator applications. These materials are employed as symmetric supercapacitors; owing to the concomitant effect of the hierarchically arranged carbon skeleton and KOH activation, a maximum Cp of 294 F g−1 with a capacitance retention of 93% after 2500 cycles at 50 mV s−1 is achieved. The multifunctionality of the composite aerogels opens new possibilities for the use of biomass‐derived materials in energy storage and sensing applications.

Zeolitic imidazolate framework (ZIF-8) nanocrystals were uniformly grown on the surface of cellulose nanocrystals (CNCs) to give a hybrid material, ZIF@CNCs. By varying the stoichiometry of the components, it was possible to control the size of the ZIF-8 crystals grown on the CNC surface. Optimized ZIF@CNC (ZIF@CNC-2) was used as a template to synthesize a microporous organic polymer (MOP),

Films of cellulose nanocrystals (CNCs) with chiral nematic organization can show vivid iridescence that arises from their hierarchical structure. Unfortunately, the brit-tleness of the films limits their potential applications. In...

Photonic materials based on composite films of cellulose nanocrystals (CNCs) and polymers are promising as they can be renewable and show tunable optical and mechanical properties. However, the influence of polymers on CNC self-assembly is not always well understood, and conflicting results are present in the literature. In this study, we incorporate three neutral, water-soluble polymers−poly­(ethylene glycol) (PEG), poly­(vinyl pyrrolidone) (PVP), and poly­(acrylic acid) (PAA)−with different molecular weights into CNC suspensions at various concentrations prior to obtaining iridescent composite thin films by solvent evaporation. Through spectroscopic, potentiometric, and rheological analyses, we find that PVP physically adsorbs to the surface of CNCs resulting in a bathochromic shift in film color with both increasing concentration and polymer molecular weight. In contrast, PEG induces depletion interactions that result in a decrease in the size of chiral nematic CNC domains, with a negligible change in film color. Finally, PAA hydrogen bonds to the hydroxyl groups of CNCs, resulting in a bathochromic color shift along with interesting rheological and liquid-state properties. This work demonstrates a deeper understanding of CNC–polymer interactions during coassembly and formation of iridescent chiral nematic films, allowing for greater control over optical properties of future CNC-based materials.