Photoinduced antimicrobial polymer blends with benzophenone as a functional additive

Abstract

Benzophenone (BP)-incorporated polymer films including polystyrene (PS), polyethylene (PE), polypropylene (PP), and polyvinyl alcohol (PVA) films were prepared, and the structural and photoactivated properties were investigated by SEM, XRD, DSC, antimicrobial, and hydrogen peroxide (H 2 O 2 ) production tests. When the amount of incorporated BP concentration was 0.5 wt %, the polymer films were successfully prepared without significant changes in physical properties. Also, all the BPincorporated polymer films showed antimicrobial abilities under UVA (365 nm) irradiation, and the effectiveness increased as the amounts of BP in the polymers are increased. On the other hand, it was observed that photoirradiated PVA/BP composite films created H 2 O 2 under the atmospheric dark condition.

Antimicrobial activity of organic photosensitizers embedded in electrospun nylon 6 nanofibers

“…As shown in Scheme , the chromophoric group (carbonyl group) of the organic photosensitizers undergoes light excitation from n to π* triplet states through UVA irradiation. The triplet tends to abstract atoms from any active hydrogen sources and can also be quenched by oxygen and moisture in the air to form a hydroperoxyl radical, a hydroxyl radical as well as a ketyl radical 9. Most likely, biological agents and toxic materials serve as sources of active hydrogen that result in an antimicrobial effect; subsequently, fibers containing a photosensitizer would be easily excited to give active radicals that can decompose bacteria when activated by UV light.…”

“…To supplement these limitations, it is necessary to study organic photosensitizers to improve applications to organic polymer materials as well as the ability to retain performance properties and durability. Studies on benzophenone and derivatives among various organic photosensitizers have been actively conducted 8–10. In particular, the chromophoric groups of organic photosensitizers such as benzophenone (known to undergo light excitation to n, π* triplet states) are commonly used as photosensitizers 8.…”

“…The triplet structure can be easily quenched with oxygen; in addition, it extracts a hydrogen atom from any active hydrogen sources to form a ketyl radical. Harmful materials in contact with the ketyl group are oxidized and destroyed 8, 9. However, the efficiency of organic photosensitizers is still lower than that of inorganic photosensitizers.…”

“…Photoactivity and mechanical properties of films containing various photosensitizers were significantly affected by the type and the amount of photosensitizer, and by contact areas. Therefore nylon 6 nanofibers were prepared by electrospinning after blending with selected photosensitizers identified from previous research 8–10. It is expected that the high surface area of the nanofibers will allow a reduction of the amount of photosensitizer and a reduction of the required light intensity for activation.…”

Production of sulfonated polyetheretherketone/polypropylene fibers for photoactive textiles

“…This triplet state is highly reactive to form a stable BPK radical by abstracting a hydrogen atom (Figure ). The antimicrobial effectiveness of benzophenone has been previously confirmed with different polymers . PP is an excellent candidate to assist SPEEK in the hydrogen abstraction since it possesses a labile hydrogen atom.…”