Antimicrobial activity of silver-coated hollow poly(methylmethacrylate) microspheres for water decontamination

Abstract

Background Growing microbial resistance towards the existing antimicrobial materials appears as the greatest challenge for the scientific community and development of new antimicrobial materials has become an important research objective. Results In this work, antimicrobial activity of silver-coated hollow poly(methylmethacrylate) microspheres (PMB) having a diameter of 20–80 µm was evaluated against two bacterial strains, Gram-positive Bacillus subtilis (MTCC 1305) and Gram-negative Escherichia coli (MTCC 443). The polymeric PMMA microspheres were synthesized by solvent evaporation technique and were further coated with silver (Ag) under microwave irradiation on their outer surface using an electroless plating technique. It was observed that Ag was uniformly coated on the surface of microspheres. Characterization of the coated microspheres was performed using optical microscope (OMS), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), UV–Vis spectroscopy, FTIR spectroscopy and thermogravimetric analysis (TGA) techniques. We have shown that the silver-coated microspheres were potent bactericidal material for water as they are highly active against the tested microorganisms. The results of the antibacterial tests indicated that APMB particles showed enhanced inhibition rate for both Gram-positive and Gram-negative bacteria and also exhibited dose-dependent antibacterial ability. The diameters of zone of inhibition were14.3 ± 0.2 mm against B. subtilis and 15.2 ± 0.9 mm against E. coli at a concentration of 8 mg. At this concentration, total removal of both Bacillus subtilis and Escherichia coli was observed. The results of shake flask technique for a concentration of 8 mg showed no bacterial presence after 24 h in both the cases. In other words, the material acted efficiently in bringing down the bacterial count to zero level for the tested strains. During the experiments, we have also confirmed that use of this material for water disinfection does not cause leaching of silver ion in to the water solution. The material can be successfully regenerated by backwashing with water. Conclusions Considering the cost-effective synthesis, ability to regenerate and very low level of leaching of the material, it can be projected as an advanced material for water disinfection and antimicrobial application.

Mercaptopurine-Loaded Sandwiched Tri-Layered Composed of Electrospun Polycaprolactone/Poly(Methyl Methacrylate) Nanofibrous Scaffolds as Anticancer Carrier with Antimicrobial and Antibiotic Features: Sandwich Configuration Nanofibers, Release Study and in vitro Bioevaluation Tests

“…Also, there are many studies used biodegradable PCL-based films incorporated with PMMA and different drugs or nanoparticles which reported that these mats have no antimicrobial activities individually. 40–42 …”

“…Also, there are many studies used biodegradable PCLbased films incorporated with PMMA and different drugs or nanoparticles which reported that these mats have no antimicrobial activities individually. [40][41][42] Different mats compositions of electrospun PMMA/PCL/ 6-MP nanofibers coded as (A) (8% PCL/4% PMMA/1% 6-MP), (B) (4% PCL/4% PMMA/1% 6-MP), and (C) (2% PCL/4% PMMA/1% 6-MP) were tested against extensively drug-resistant human pathogens (Klebsiella rhinoscleromatis, Streptococci sp., and Candida tropicalis) as shown in Figure 9. We noticed that, the highest inhibition zones were found for NFs (2% PCL/4% PMMA/1% 6-MP) (C) against Candida tropicalis (39.43±3.5), and Klebsiella rhinoscleromatis (35.37 ±0.9) followed by Streptococci sp., (29.25±2.2).…”

Facile Deposition of Silver Nanoparticles on Photonic Cellulose Nanocrystals Films: A Study on Solvent Stability and Post Antibacterial Activity

“…Primarily, the cells getting in contact with silver take‐up the silver ions which damages the bacterial cell membrane. [ 44,45 ] Second, the generation of reactive oxygen species through inhibition of respiratory enzymes by silver ions damages the bacterial cell itself. In this study, when bacterial culture was treated with the inhibitory concentrations of photonic films, the E. coli physically contacts the photonic films, leading to cell wall pitting (Figure 6b), that is enough to cause bacterial death.…”

Antimicrobial and mechanical properties of functionalized textile by nanoarchitectured photoinduced Ag@polymer coating

“…As the nanoparticles are embedded inside the polymer matrix, they are protected from external forces, which ultimately extends the lifetime of the functionalized textile. The antimicrobial properties of MNP-polymer composites have been extensively investigated [ 42 – 44 ] and research has gone into functionalizing textile fibers with the nanocomposites in situ [ 45 – 46 ]. Few studies seem to have been carried out on the coating of unaltered textile substrates with hybrid MNP-polymer films for antimicrobial applications.…”