Plastic packaging effectively protects food from mechanical, microbial, and chemical damage; however, oxygen and moisture permeate these plastics and spoil the food. Thus, the gas barrier function is usually imparted through metallic or halogenated polymeric coatings. However, the former blocks visible light, while the latter causes environmental concerns. Moreover, plastic packaging contaminated with food scraps and stains requires a washing process for recycling. To satisfy the key requirements for food packaging, we fabricated a (1) sustainable, (2) self-cleaning, (3) transparent, and (4) oxygen/moisture barrier coating on poly(ethylene terephthalate) (PET) film. A spray-assisted layer-by-layer assembly of negatively charged cellulose nanofibers and positively charged chitosan nanowhiskers was coated on one side of the PET film. Salt bridge-mediated synergistic interplay between these highly crystalline nanomaterials imparted a low oxygen transmission rate of less than 0.1 mL m⁻² day⁻¹. The other side of the PET film was formed with a porous surface by spray-coating of silica nanoparticles and chitosan nanowhiskers. Thereafter, the porous surface was impregnated with bio-based sunflower oil. This side repelled the contaminants and exhibited a low water vapor transmission rate of 1.4 g m⁻² day⁻¹. The gas barrier performance meets the packaging requirements for most food products. This coating has high potential for sustainable packaging applications.

Polycarbonate (PC) is a transparent polymeric material which can replace shattering glass, but bisphenol-A, used for improving its properties, has controversial hazards. An alternative biomass-derived isosorbide (ISB)-based PC can be used owing to its complementary properties. To satisfy the two factors of sustainability and performance simultaneously, this paper proposes the in situ polymerization of ISB pre-dispersed with cellulose nanocrystals (CNCs), which directly produces PC nanocomposites, as a facile method for achieving record-high mechanical strength among all types of PCs and their nanocomposites. The proposed nanocomposite is more transparent, exhibits an ultimate tensile strength of 93 MPa and a 4.3-fold increased toughness of 40 MJ m⁻³, compared to a homo-polymer, and is better than post-blended nanocomposites due to the excellent dispersibility of 0.3 wt% nanofiller. Formidable improvements in in situ PC/CNC nanocomposites originate from the simultaneous contributions of covalent and physical interactions through polymeric grafting on the CNC surface and hydrogen bonding with a polar ISB moiety of PC, in advance, from the monomer dispersion, respectively, enhancing the interfacial interaction with the polymer matrix. This in situ approach opens new possibilities in the field of sustainable plastic industries.

Hyaluronated fullerene has strong near-infrared (NIR) fluorescence intensity without labelling with any fluorophores or isotopes. This fullerene allowed high-resolution fluorescent imaging of tumor sites in vivo and resulted in a significant regression of HCT-116 tumors.