%0 Journal Article
%T Necrosis of Staphylococcus aureus by the Electrospun Fe- and Ag-Doped TiO2 Nanofibers
%A Asem Aboelzahab
%A Abdul-Majeed Azad
%A Vijay Goel
%J ISRN Orthopedics
%D 2012
%R 10.5402/2012/763806
%X Postsurgery infections cause prolonged hospitalization, incurring increased patient and hospital costs, making it increasingly vital to develop an effective solution for the mitigation and elimination of infection buildup at these sites. Incorporation of a bactericidal device at the infection-prone sites provides the capability of attacking bacterial growth even after the patient has left the hospital. Polycrystalline titanium dioxide (TiO2) is photoactive and possesses antibacterial properties that can mitigate the onset of these infections and aid in wound healing. In this work, TiO2 nanofibers were synthesized by electrospinning. Doping with iron as well as with silver (5£¿wt% and 1£¿wt%, resp.) was also carried out to increase their effectiveness towards bactericidal properties. The electrospun fibers were processed and tested in the presence of light in the suspensions of methicillin-susceptible Staphylococcus aureus (MSSA) bacteria, which are the leading infection-inducing bacteria among hospital patients. It was found that upon brief activation (cf. 30£¿s) by an infrared laser source, greater than 90% of the S. aureus was rendered inactive within cf. 10£¿min. of exposure, thereby showing the potential of titania nanofibers for effective mitigation of infection. 1. Introduction Infections caused by bacteria could pose harmful attacks on human tissues to a point where fighting them off becomes increasingly difficult. Though the source and reasons of infection and propagation are multifarious, the consequences could be debilitating and disastrous. In addition to the health risk, the financial costs are also huge. The gram-positive Staphylococcus aureus (S. aureus) microorganism is the leading cause of infection in healthcare settings where even antibiotic treatment has proven to be exhausted without appreciable effect in many cases [1¨C4]. One study containing data accumulated over a three-year period of patients admitted to a Boston hospital revealed a mortality rate of 22.9% in patients diagnosed with MSSA and methicillin-resistant S. aureus (MRSA) infection, with average lengths of stay between 7 and 9 days and hospital charges between $19,000 and $26,000, respectively [5]. The photocatalytic/antibacterial behavior of titania nanoparticles and their ability to inhibit bacterial proliferation by inducing cell necrosis have been extensively reported [10¨C14]. Recently, the efficacy of self-standing electrospun TiO2 nanofibers and nanofilm coatings on Ti substrates (plates and wires), in initiating the necrosis of E. coli cells upon brief activation by
%U http://www.hindawi.com/journals/isrn.orthopedics/2012/763806/