Biofilm Inhibition by Nanoparticles - Antibiofilm Agents: From Diagnosis to Treatment and Prevention - page 381

(Sankar et al. 2013 ). Iron nanoparticles coupled with high-resolution MRI detected
lymph node metastases in patients with prostate cancer at a stage undetectable by
any other method (Harisinghani et al. 2003 ) and the gold nanoparticles were
employed for the accurate detection of matriptase—a cancer biomarker protein
overexpressed in all types of cancer (Deng et al. 2013 ). Lastly, nanoparticles made
of compounds with oxygen vacancies (CeO 2 and Y 2 O 3 ) (Schubert et al. 2006 ) have
been demonstrated to possess neuroprotective and anti-apoptotic properties.

3.3 Antimicrobial Activity of Nanoparticles

Nanoparticles have been considered to be some of the most effectual bioactive
agents mainly because of their large surface area to volume ratio (Hamouda 2012 ).
Nanopowders possess antimicrobial properties against various bacterial, fungal and
viral human pathogens (Koper et al. 2002 ; Bosi et al. 2003 ) and can rapidly kill
bacterial cells (90 % in 1 h). The antibacterial properties of silver and titanium
dioxide nanoparticles have been assessed as coatings for surgical masks

(Li et al. 2006 ), in addition to many other clinical uses.
Nanoparticles shown to have antimicrobial effects include silver (Lara
et al. 2010 ; Lok et al. 2006 ), titanium dioxide (Li et al. 2006 ), fullerenes (Bosi
et al. 2003 ), zinc oxide (Brayner et al. 2006 ), and magnesium fluoride (Lellouche
et al. 2012c ). The antibacterial activity of fullerenes was reported against
Escherichia coli , Salmonella and Streptococcus spp. (Bosi et al. 2003 ). The ability
of zinc oxide nanoparticles to disturb the membrane permeability of E. coli has also
been reported (Brayner et al. 2006 ). The wide spectrum antimicrobial activity of
silver nanoparticles has been attributed to their ability to destabilize the bacterial
outer membrane and deplete adenosine triphosphate (principal form of energy) in
bacteria (Lara et al. 2010 ; Lok et al. 2006 ).
Fullerenes have also been shown to have neuroprotective, anti-apoptotic, and
anti-HIV activities (Bosi et al. 2003 ). Size-dependent interactions of silver
nanoparticles and HIV-1 virus were reported, which resulted in the inhibition of
host-viral interactions (Elechiguerra et al. 2005 ). Numerous other studies have
demonstrated the antimicrobial potential of various nanoparticles and drug-nano-
particle conjugates against bacterial, fungal, and viral pathogens (Zheng et al. 2013 ;
Zhao et al. 2013a ; Zhang et al. 2013c ; Xiong et al. 2013 ; Westendorf 2013 ; Wang
and Lim 2013 ; Wang et al. 2013 ; Vidic et al. 2013 ; Tavassoli Hojati et al. 2013 ;Su
et al. 2013 ; Shimizu et al. 2013 ; Mohanty et al. 2012 ; Mallick et al. 2012 ; Lellouche
et al. 2012a ; Costa et al. 2011 ; Mukhopadhyay et al. 2010 ; Huda et al. 2010 ; Sanpui
et al. 2008 ; Pinto et al. 2013 ; Hernandez-Delgadillo et al. 2013 ; Monteiro
et al. 2012 ; Khan et al. 2012 ; Lara et al. 2010 ).