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ABSTRACT Formation of alginate‐based interpenetrating networks and addition of nanoparticles into these gels are widely used strategies to enhance the mechanical properties of alginate gels used for delivery and biomedical applications. Our previous work demonstrated that alginate‐clay nanocomposite hydrogels containing poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (PEO–PPO–PEO) copolymers exhibited significant enhancement of elasticity and temperature‐dependent rheology. However, the behavior of PEO–PPO–PEO copolymers within an alginate network remains unclear. In this study, we use small‐angle neutron scattering (SANS) to investigate the interactions between the alginate network and PEO–PPO–PEO triblock chains. Our fitting results revealed that the triblock chains can form micelles integrated into the alginate gel “egg box” structure at higher temperatures. The presence of the alginate network influences the formation of PEO–PPO–PEO micelles in our gels, leading to elongated ellipsoidal micelles rather than spherical micelles. Interestingly, as the temperature increased, these micelles did not expand in all three dimensions, as observed for pure PEO–PPO–PEO solutions. Rather, the total size increased only in one direction while remaining the same in the other two directions, suggesting that the alginate networks restrict the growth of micelles. Furthermore, we did not observe the distinct higher‐order peaks that are typical of cubic PEO–PPO–PEO hydrogels; rather, relatively weak secondary peaks were observed. These results demonstrate that the presence of the alginate network significantly influences micelle formation and assembly in composite hydrogel systems. 

Vaccines are a pivotal achievement in public health, offering inexpensive, distributable and highly effective protection against infectious diseases. Despite significant advancements in vaccine development, there are still many diseases for which vaccines are unavailable or offer limited protection. The global impact of the deficiency in vaccine‐induced immunity against these diseases is profound, leading to increased rates of illness, more frequent hospitalizations, and higher mortality rates. Recent studies have demonstrated conjugation mechanisms and delivery methods to co‐present adjuvants and protein epitopes to antigen‐presenting cells, significantly enhancing adaptive immunity. We introduce a novel approach to incorporate an adjuvant into the vaccine by covalently attaching it to whole enveloped virions. Using clickable azide‐enabled viral particles, generated through metabolic incorporation of N‐azidoacetyl glucosamine (GlcNAz), we conjugated the virions with a cyclo‐octyne‐modified CpG‐ODN. Conjugation yielded a potent adjuvant‐virus complex, eliciting higher TLR9‐mediated cell activation of cultured bone marrow‐derived macrophages relative to co‐administered adjuvants and virions. Administration of covalent adjuvant‐virion conjugates increase immune cell stimulation and may provide a generalizable and effective strategy for eliciting a heightened immune response for vaccine development. 

To understand the relationship between the intermolecular structure of aromatic polyamide (PA) scaffold and the water molecules in the barrier layers of reverse osmosis (RO) membranes, a grazing incidence wide-angle X-ray scattering (GIWAXS) study was carried out on freestanding PA thin films at varying relative humidity (RH) conditions. The scattering results were analyzed by an interference scattering model, containing a phase factor between a PA chain and an adsorbed water molecule. This model yielded good fits to the GIWAXS profiles where the water adsorption was found to vary linearly with RH. Atomistic molecular dynamics (MD) simulations were also performed to complement the experimental study. The simulations revealed that a rapid condensation layer initially formed on the PA film surface, followed by the slow water molecule diffusion inside the PA membrane. Sparse adsorbed water, isolated in subnanopores of the PA film adjacent to the polar atoms, even in very low quantities, modifies the X-ray scattering. Atomistic simulations at the microscopic scale provide partial support for several X-ray scattering findings.