Green Formation of Robust Supraparticles for Cargo Protection and Hazards Control in Natural Environments

Abstract

In parallel with important technological advances, nanoparticles have brought numerous environmental and toxicological challenges due to their high mobility and nonspecific surface activity. The hazards associated with nanoparticles can be significantly reduced while simultaneously keeping their inherent benefits by superstructuring. In this study, a low-temperature and versatile methodology is employed to structure nanoparticles into controlled morphologies from biogenic silica, used as a main building block, together with cellulose nanofibrils, which promote cohesion. The resultant superstructures are evaluated for cargo loading/unloading of a model, green biomolecule (thymol), and for photo-accessibility and mobility in soil. The bio-based superstructures resist extremely high mechanical loading without catastrophic failure, even after severe chemical and heat treatments. Additionally, the process allows pre and in situ loading, and reutilization, achieving remarkable dynamic payloads as high as 90 mg g . The proposed new and facile methodology is expected to offer a wide range of opportunities for the application of superstructures in sensitive and natural environments.

Spherical lignin particles: a review on their sustainability and applications

“…delivery platforms where nanoparticles may be too mobile. 60 Such microclusters can be redispersed by either tip or bath ultrasound or high-shear homogenization (Ultra-Turrax). Dry lignin nanoparticles have also been formed by evaporating solvents from a reverse micelle dispersion of lignin, 53 and by using a so-called ice segregation method, which involves freezing lignin solutions on cold surfaces.…”

Two‐Phase Emulgels for Direct Ink Writing of Skin‐Bearing Architectures

“…The adoption of silica‐loaded hydrogel was inspired from our previous report wherein mechanically robust materials were produced after drying suspensions containing silica microparticles and CNF . Herein, the hydrogel was formed by the addition of poly(acrylic acid) (PAA) that is cross‐linked in the presence of ammonia solution .…”

“…For a neat hydrogel ink (ESR0), a homogeneous arrangement of particles and fibrils was observed across the structure of the printed filaments or struts (Figure a 1 ). This is owing to the ability of CNF/PAA to bind strongly with silica particles after cross‐linking (Figure a 2 ) . The cross‐section of ESR0 indicates filaments comprising well‐packed networks of silica particles (Figure S6a, Supporting Information).…”

“…Co., Newton, MA), as described previously . ChNF were extracted from crabs following a series steps of washing, decolorizing, deacetylation, and ultrasonication, according to the procedures described previously . PLA 6060D ( M w = 191 000) was kindly provided by Nature Works, United States.…”

“…Preparation of All‐in‐One Two‐Phase Emulgel as Ink for DIW : Pickering emulsions were prepared similarly as previous studies 23b,24. Suspensions of CNF and ChNF were both diluted to 0.5 wt% and then mixed thoroughly to obtain homogeneous suspension (Figure S1a, Supporting Information).…”