Colloids and Surfaces B: Biointerfaces 96 (2012) 69–74 Contents lists available at SciVerse ScienceDirect Colloids and Surfaces B: Biointerfaces jou rn al h om epage: www.elsevier.com/locate/colsurfb Biosynthesis of silver nanoparticles from Tribulus terrestris and its antimicrobial activity: A novel biological approach V. Gopinath a , D. MubarakAli b , S. Priyadarshini a , N. Meera Priyadharsshini a , N. Thajuddin b , P. Velusamy a,∗ a Department of Biotechnology, School of Bioengineering, SRM University, Kattankulathur, Chennai 603203, Tamil Nadu, India b Department of Microbiology, School of Lifesciences, Bharathidasan University, Tiruchirappalli 620024, India a r t i c l e i n f o Article history: Received 27 December 2011 Accepted 30 March 2012 Available online 6 April 2012 Keywords: Biosynthesis Silver nanoparticles TEM Tribulus terrestris L. Fruit bodies Antibacterial Green chemistry a b s t r a c t In the recent decades, increased development of green synthesis of nanoparticles is inevitable because of its incredible applications in all fields of science. There were numerous work have been produced based on the plant and its extract mediated synthesis of nanoparticles, in this present study to explore that the novel approaches for the biosynthesis of silver nanoparticles using plant fruit bodies. The plant, Tribulus terrestris L. fruit bodies are used in this study, where the dried fruit body extract was mixed with silver nitrate in order to synthesis of silver nanoparticles. The active phytochemicals present in the plant were responsible for the quick reduction of silver ion (Ag + ) to metallic silver nanoparticles (Ag 0 ). The reduced silver nanoparticles were characterized by Transmission Electron Microscope (TEM), Atomic Force Micro- scope (AFM), XRD, FTIR, UV–vis spectroscopy. The spherical shaped silver nanoparticles were observed and it was found to be 16–28 nm range of sizes. The diffraction pattern also confirmed that the higher percentage of silver with fine particles size. The antibacterial property of synthesized nanoparticles was observed by Kirby–Bauer method with clinically isolated multi-drug resistant bacteria such as Strepto- coccus pyogens, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis and Staphylococcus aureus. The plant materials mediated synthesis of silver nanoparticles have comparatively rapid and less expensive and wide application to antibacterial therapy in modern medicine. © 2012 Elsevier B.V. All rights reserved. 1. Introduction Nanotechnology provides the tools and technology platform for the investigation of biological systems, and biology offers inspi- ration models for bio-assembled components to nanotechnology. Nanostructured materials showed many aspects of interesting characteristics, i.e., optical, catalytic, that greatly depends on the size and shape of nanoparticles as an effect of quantum confine- ment of electrons. Metal nanoparticles are extensively used in many electrochemical, electro analytical and bio-electrochemical applications owing to their extraordinary electro catalytic activity [1]. Nanoparticle research is inevitable today not because of only application and also by the way of synthesis. Route of synthesis of nanoparticles by physical and chemical methods may have consid- erable environmental defect, technically laborious and economi- cally expensive. Many researchers have explored the technological ∗ Corresponding author. Tel.: +91 8939731191. E-mail addresses: vels73@gmail.com, velusamy.p@ktr.srmuniv.ac.in (P. Velusamy). approach for the synthesis. For example, silver ions are reduced by chemical, electrochemical, radiation, photochemical methods; Langmuir–Blodgett and biological techniques were reviewed [2]. Biological route synthesis of nanoparticles have much attention focused by researcher for the reason that to elucidate the mecha- nism of synthesis. Almost all type of biological entity has been used for the synthesis of nanoparticles with size and shape controlled manner. First and foremost, a microorganism, Pseudomonas stutzeri AG259 have used for the synthesis of silver nanoparticles [3], later on actinomycetes [4], fungi [5], cyanobacteria [6], biomolecules [7] and different parts of plant materials. The plant material based production of nanomaterials has wide range of application such as antimicrobial property. Various plant materials have been stud- ied so far for the synthesis of silver, gold, platinum and titanium nanoparticles in different sizes and shapes were tabulated (Table 1). In recent days, different parts of plant materials have been studied for this direction more exclusively such as extracts [1], fruit [8], bark [9], fruit peels [10], root [2] and callus [11]. In this present study to explore that the novel approaches for the biosynthesis of silver nanoparticles using dried fruit bodies from the plant, Tribulus terrestris L. is belongs to the family Zygo- phyllaceae and it has long been used in the traditional Chinese and 0927-7765/$ – see front matter © 2012 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.colsurfb.2012.03.023