The effectiveness of the metal oxide nanoparticles viz. CuO and Fe 2 O 3 as antibacterial agents against multidrug resistant biofilm forming bacteria was evaluated. CuO nanoparticles were also experimented for antibiofilm and time kill assay. The CuO displayed maximum antibacterial activity with zone of inhibition of (22 ± 1) mm against methicillin resistant Staphylococcus aureus (MRSA) followed by Escherichia coli (18 ± 1) mm. The Fe 2 O 3 showed the zone of inhibition against MRSA of (14 ± 1) mm followed by E. coli (12 ± 1) mm. CuO proved to be more toxic than Fe 2 O 3 nanoparticles showing significantly high antibacterial activity and found to possess dose dependent antibiofilm properties.Biofilm can be defined as the microbial-derived sessile communities characterized by the cells that remain attached to any surface. Quorum sensing among the biofilm forming organisms plays significant role in the formation of biofilm [4,6]. Urinary catheters when inserted into the human body parts, may readily acquire biofilm. Eradication of the biofilm is very hard and cause many chronic infections. Recent research work reveals that use of quorum sensing inhibitors could be useful for restricting biofilm formation [3,5]. Nanoparticles have good antibacterial activity and they could be used as an effective bactericidal agent [8,10,11]. Considering the above facts, experiment was conducted for detection of biofilm producing uropathogens and antibacterial/antibiofilm activity of iron oxide and copper oxide nanoparticles against multidrug resistant biofilm forming uropathogens was investigated.A total of 50 samples and 213 isolates were screened for the biofilm production. All the clinical samples were collected from hospitalized female patients with urinary catheter inserted for more than 2 days from government hospitals in Sonitpur (Tezpur) (Lat. 26.63°N Long. 92.8°E) and Dibrugarh (Lat. 27.48°N Long. 95°E) districts of Assam, India.The biofilm formation was analyzed by different standard methods [9]. Table 1 represented biofilm formation by uropathogens isolated from urine of normal and hospitalised females with urinary catheter inserted. Among 168 clinical samples maximum 88 isolates (52.4 %) of uropathogens were detected as biofilm former in Microtitre plate method. Among different biofilm formers Escherichia coli detected as maximum biofilm producer with 24 isolates (80 %) followed by Proteus mirabilis, 16 isolates (72.73 %); Staphylococcus aureus, 16 isolates (57.1 %); Enterococcus faecalis, 14 isolates (53.8 %); Pseudomonas species 14 isolates (43.8 %) and Staphylococcus epidermidis 4 isolates (40 %).Antibiotic resistance of different kinds of uropathogens was studied by Kirby-Bauer disc diffusion method on MHA plates, which revealed that resistance was higher in biofilm formers than in non-biofilm formers. Three antibiotics namely penicillin, ampicillin and piperacillin were found to be resistant equally in both biofilm formers (100 %) and non-biofilm formers (100 %). Among Grampositive biofilm formers, oxacil...

Foley's catheters were coated with Silver (Ag), plasma polymerized aniline (PPAni) and Ag-PPAni composite by plasma based deposition processes which were characterized by XRD, EDX, SEM, and FT-IR spectroscopy and bioassays were performed to validate their efficacies to kill planktonic cells as well as to remove biofilm. The analyses confirmed the formation of Ag nanoparticles (AgNPs), PPAni and Ag-PPAni composite and also corroborated their successful deposition over the catheters. Antibacterial assays showed that coated catheters were capable of killing planktonic cells of most commonly encountered uropathogens and equally capable of eradicating biofilm formation by the uropathogens as evident from the reduced cfu/ml. UV-vis spectroscopy results showed that the nanoparticle coated catheters were capable of gradual release of AgNPs, killing all planktonic cells in solution over the time. Foley's catheters coated with AgNPs and their composites by one step plasma process were non-toxic devices capable of killing planktonic cells and proficient in eradicating biofilm formation which could be used to cutback the likelihood of the catheter related complications.

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