title: Antimicrobial PVK:SWNT nanocomposite coated membrane for water purification: performance and toxicity testing.
abstract: This study demonstrated that coated nitrocellulose membranes with a nanocomposite containing 97% (wt%) of polyvinyl-N-carbazole (PVK) and 3% (wt%) of single-walled carbon nanotubes (SWNTs) (97:3 wt% ratio PVK:SWNT) achieve similar or improved removal of bacteria when compared with 100% SWNTs coated membranes. Membranes coated with the nanocomposite exhibited significant antimicrobial activity toward Gram-positive and Gram-negative bacteria (≈ 80-90%); and presented a virus removal efficiency of ≈ 2.5 logs. Bacterial cell membrane damage was considered a possible mechanism of cellular inactivation since higher efflux of intracellular material (Deoxyribonucleic acid, DNA) was quantified in the filtrate of PVK-SWNT and SWNT membranes than in the filtrate of control membranes. To evaluate possible application of these membrane filters for drinking water treatment, toxicity of PVK-SWNT was tested against fibroblast cells. The results demonstrated that PVK-SWNT was non toxic to fibroblast cells as opposed to pure SWNT (100%). These results suggest that it is possible to synthesize antimicrobial nitrocellulose membranes coated with SWNT based nanocomposites for drinking water treatment. Furthermore, membrane filters coated with the nanocomposite PVK-SWNT (97:3 wt% ratio PVK:SWNT) will produce more suitable coated membranes for drinking water than pure SWNTs coated membranes (100%), since the reduced load of SWNT in the nanocomposite will reduce the use of costly and toxic SWNT nanomaterial on the membranes.
authors.affiliation: Department of Civil and Environmental Engineering, University of Houston, 4800 Calhoun Rd, Houston, TX 77204-5003, USA.
authors.forename: Farid
authors.initials: F
authors.lastname: Ahmed
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Santos
authors.forename: Joey
authors.initials: J
authors.lastname: Mangadlao
authors.forename: Rigoberto
authors.initials: R
authors.lastname: Advincula
authors.forename: Debora F
authors.initials: DF
authors.lastname: Rodrigues
mesh_terms: D000362:Agar; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification / Q000648:ultrastructure; D016923:Cell Death / Q000187:drug effects; D004269:DNA, Bacterial / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D005374:Filtration / Q000295:instrumentation; D008567:Membranes, Artificial; D051379:Mice; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects; D041681:NIH 3T3 Cells; D053761:Nanocomposites / Q000633:toxicity* / Q000648:ultrastructure; D037742:Nanotubes, Carbon / Q000633:toxicity* / Q000648:ultrastructure; D056951:Photoelectron Spectroscopy; D011145:Polyvinyls / Q000633:toxicity*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D018675:Toxicity Tests; D014780:Viruses / Q000187:drug effects / Q000302:isolation & purification; D018508:Water Purification
chemical_list: D000890:Anti-Infective Agents; D004269:DNA, Bacterial; D008567:Membranes, Artificial; D037742:Nanotubes, Carbon; D011145:Polyvinyls; C035125:poly-N-vinylcarbazole; D000362:Agar