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Antibacterial glass mat sheets containing unsaturated polyester resin as a matrix and poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA)-functionalized multi-walled carbon nanotube (MWNT) nanocomposites as a filler were prepared. Controlled functionalization of MWNT by in situ atom transfer radical polymerization (ATRP) of DMAEMA was applied for the preparation of nanocomposites. An antibacterial activity of the prepared unsaturated polyester glass mat sheets was determined by the application of film contact method based on the Japanese Industrial Standard JIS Z-2801. The mechanical properties of the prepared unsaturated polyester glass mat sheets were estimated by the simplified procedure designed in laboratory. A deliberate search for the ATRP process conditions showing the most effective antibacterial activity was tried beyond all experiments.

Ag/TiO₂ coating was prepared by anodizing the surface of Ti followed by electrodeposition of silver. By X-ray diffraction (XRD) analyses, that indicated the crystalline size of Ag deposit onto the oxidized surface of Ti was around 32 nm. Scanning electron microscopy (SEM) images of the oxidized surface with and without Ag deposit show that TiO₂ is formed uniformly but Ag deposit consisted of numerous spherical structures. The Escherichia coli and Staphylococcus aureus bacteria were utilized to test the antibacterial effect of Ag/TiO₂ coating which showed more than 99% of bacteria were killed after 24 h incubation. The results of in vitro test showed Ag/TiO₂ coating is also biocompatible.

A poly(ethylene glycol) (PEG)-conjugated silicon(IV) phthalocyanine axially substituted with (PEG1000) chains (SiPc-PEG) was synthesized, and this novel phthalocyanine was characterized by ${}^{\mathrm{\text{1}}}$H-NMR, FT-IR and UV-Vis spectrophotometric methods. Elemental analysis data were beneficial for the evaluation of the chemical structure of the new compound. The total number of (O–CH${}_{\mathrm{\text{2}}}$–CH${}_{\mathrm{\text{2}}}$ units was calculated as 44 and the structure of the new PEG-conjugated silicon phthalocyanine was determined by the use of integral areas in ${}^{\mathrm{\text{1}}}$H-NMR spectrum and the ratio of SiPc:PEG1000 was found as 1:2. The photophysical and photochemical properties were determined in both DMSO and aqueous solutions. In addition, the photocytotoxicity of the novel PEG-conjugated silicon(IV) phthalocyanine was also examined by testing against human cervical-carcinoma (HeLa) and hepato-carcinoma cells (HuH-7). The IC${}_{\mathrm{\text{50}}}$ value for the SiPc-PEG compound was determined as 0.28 $\mu$M for HeLa cells and 0.4 $\mu$M for HuH-7 cells. These results imply that HeLa cells are apparently more responsive to photodynamic therapy (PDT) treatment by SiPc-PEG than HuH-7 cells at low concentrations (up to 0.5 $\mu$M) of the studied photosensitizer. Additionally, SiPc-PEG showed antibacterial activity against Escherichia coli at 48 h of incubation, the viabilities of E.coli cultures exposed to 1000 $\mu$g/mL and 2500 $\mu$g/mL SiPc-PEG concentration were reduced by about 90%, and the additional growth inhibitory effect of photoactivation was also observed clearly at these efficient concentrations. To conclude, the novel compound may have a high potential for photodynamic therapy.

Silver nanoparticles have attracted much interest from scientists to develop nanosilver-based disinfectant products due to their unique properties of high antimicrobial activity. This study focused on biosynthesis, characterization, antimicrobial and antibiofilm effects of silver nanoparticles against vegetative and starved Shigella strains. The silver nanoparticles were synthesized using the yeast Yarrowia lipolytica and characterized by ultraviolet–visible spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The antimicrobial and antibiofilm activities of silver nanoparticles were tested against the growth of vegetative and starved Shigella strains. After the addition of silver nitrate solution to the supernatant of Y. lipolytica, we noticed the appearance of a brown-black coloration that suggested the formation of silver nanoparticles. The presence of silver nanoparticles was manifested by a maximum absorption in the ultraviolet–visible range, precisely at the wavelength 420nm. The crystalline nature and the stability of silver nanoparticles were confirmed, respectively, by XRD and FTIR analysis. The antibacterial activity of silver nanoparticles showed significant toxicity on Shigella strains indicating that the starved cells were more sensitive to treatment with silver nanoparticles than vegetative cells. Surprisingly, the biofilm formation had not been inhibited by silver nanoparticles for both vegetative and starved cells. In conclusion, a new class of nanosilver containing disinfectant nanoproducts will be promising for advanced environmental treatments including air disinfection, water disinfection, surface disinfection and personal hygiene that will help to prevent the further outbreak of diseases.