2 research outputs found
Polypropylene-Rendered Antiviral by Three-Dimensionally Surface-Grafted Poly(<i>N</i>‑benzyl-4-vinylpyridinium bromide)
To inhibit viral
infection, it is necessary for the surface of
polypropylene (PP), a polymer of significant industrial relevance,
to possess biocidal properties. However, due to its low surface energy,
PP weakly interacts with other organic molecules. The biocidal effects
of quaternary ammonium compounds (QACs) have inspired the development
of nonwoven PP fibers with surface-bound quaternary ammonium (QA).
Despite this advancement, there is limited knowledge regarding the
durability of these coatings against scratching and abrasion. It is
hypothesized that the durability could be improved if the thickness
of the coating layer were controlled and increased. We herein functionalized
PP with three-dimensionally surface-grafted poly(N-benzyl-4-vinylpyridinium bromide) (PBVP) by a simple and rapid method
involving graft polymerization and benzylation and examined the influence
of different factors on the antiviral effect of the resulting plastic
by using a plaque assay. The thickness of the PBVP coating, surface
roughness, and amount of QACs, which jointly determine biocidal activity,
could be controlled by adjusting the duration and intensity of the
ultraviolet irradiation used for grafting. The best-performing sample
reduced the viral infection titer of an enveloped model virus (bacteriophage
Ï•6) by approximately 5 orders of magnitude after 60 min of contact
and retained its antiviral activity after surface polishing-simulated
scratching and abrasion, which indicated the localization of QACs
across the coating interior. Our method may expand the scope of application
to resin plates as well as fibers of PP. Given that the developed
approach is not limited to PP and may be applied to other low-surface-energy
olefinic polymers such as polyethylene and polybutene, our work paves
the way for the fabrication of a wide range of biocidal surfaces for
use in diverse environments, helping to prevent viral infection
Hybrid Nanocellulosome Design from Cellulase Modules on Nanoparticles: Synergistic Effect of Catalytically Divergent Cellulase Modules on Cellulose Degradation Activity
Cellulosomes, which are assemblies
of cellulases with various catalytic
functions on a giant scaffoldin protein with a carbohydrate-binding
module (CBM), efficiently degrade solid cellulosic biomass by means
of synergistically coupled hydrolysis reactions. In this study, we
constructed hybrid nanocellulosomes from the biotinylated catalytic
domains (CDs) of two catalytically divergent cellulases (an endoglucanase
and a processive endoglucanase) and biotinylated CBMs by clustering
the domains and modules on streptavidin-conjugated nanoparticles.
Nanocellulosomes constructed by separately clustering each type of
CD with multiple CBMs on nanoparticles showed 5-fold enhancement in
cellulase degradation activity relative to that of the corresponding
free CDs, and mixtures of the two types of nanocellulosomes gradually
and synergistically enhanced cellulase degradation activity as the
CBM valency increased (finally, 2.5 times). Clustering the two types
of CD together on the same nanoparticle resulted in a greater synergistic
effect that was independent of CBM valency; consequently, nanocellulosomes
composed of equal amounts of the endo and endoprocessive CDs clustered
on a nanoparticle along with multiple CBMs (CD/CBM = 7:23) showed
the best cellulose degradation activity, producing 6.5 and 2.4 times
the amount of reducing sugars produced from amorphous and crystalline
cellulose, respectively, by the native free CDs and CBMs in the same
proportions. Our results demonstrate that hybrid nanocellulosomes
constructed from the building blocks of cellulases and cellulosomes
modules have the potential to serve as high-performance artificial
cellulosomes