Vector control is an essential requirement in control of epidemic diseases such as malaria, filariasis, dengue that are transmitted by different species of mosquitoes. Emergence of insecticide resistance and their harmful effects on non-target organisms and environment has necessitated an urgent search for development of new and improved mosquito control methods that are economical and effective as well as safe for non-target organisms and the environment. Insecticides synthesized from natural products, such as silver, gold or silicon nanoparticles of herbal origin have become a priority in the search. Nanoparticles are defined as particulate dispersions or solid particles with a size of 10-1000 nm. The word “nano” is derived from a Greek word meaning “dwarf”. In technical terms, the word “nano” means 10-9 , or one billionth of a meter. Naturally, the word nanotechnology evolved due to use of nanometer size particles. Targeted nanoparticles exhibit many novel characteristic features, such as extra ordinary strength, more chemical reactivity, magnetic properties and or high electrical conductivity. “Nanotechnology” deals with application of such particles in biological, physical, chemical, environmental, agricultural, industrial or pharmaceutical science. Depending upon the method of preparation, nanoparticles, nanospheres or nanocapsules can be obtained. Although physical and chemical methods are more popular and widely used for synthesis of nanoparticles, the related environmental toxicity and nonbiodegradable nature of the products limited their applications. So, the “green” route for synthesis of nanoparticles from herbal origin is of great interest due to eco-friendliness, economic prospects, feasibility and wide range of applications (Salam et al., 2012).Mosquitoes are major public health concern at global level as they act as vectors for transmitting a number of diseases in humans. Mosquito larvae are attractive targets for devising effective control measures. Conventional methods for their control involve the use of chemical insecticides which leads to the development of resistance hence results in disease outbreaks.Nanomaterials are emerging as fastest growing materials for controlling theses vectors due totheir unique physical and chemical properties due to extremely small size and high surface area.Among different nanomaterials, silver nanoparticles (AgNPs) are most commercialized due totheir wide applications ranging from antimicrobial, biomedical, insecticidal, agriculture, biosensor and water purification. Silver nanoparticles have received considerable attention asantimicrobial agents and have been shown to be an effective antimicrobial agent.Synthesis of silver nanoparticles has been reported by a number of methods involving chemical, physical and biological synthesis. Dragieva et al. (1999) synthesized and characterized silver nanoparticles using transmission electron microscopy (TEM) and X-ray diffractometry. TEM analysis showed that AgNPs were spherical in shape and their size ranged from 40 to 60 nm. Xray diffractometry specified that the sample was crystalline and had a face centered cubicstructure of pure silver. Junjie et al. (2000) prepared silver nanoparticles of different shapes(spheres, rods, and dendrites) by using a pulse sonoelectrochemical technique from an aqueoussolution of AgNO3 in the presence of nitrilotriacetate N(CH2COOH)3-NTA. The silver nanoparticles were characterized by using TEM, X-ray diffraction, and absorption spectroscopy.It was found that the concentration of AgNO3 and NTA affects the shape of the nanoparticles.Baker et al. (2005) created nanometer sized silver particles by inert gas condensation and cocondensation techniques. A variety of chemical approaches have also been utilized to produce silver nanoparticles with different size distribution and different shapes (Prabhu et al., 2010, Sadeghi et al., 2010, Hussain et al., 2011). Das et al. (2011) prepared uniform silver nanoparticles through the chemical reduction of silver ions by ethanol in presence of sodium linoleate and checked antibacterial activity. Dong et al. (2012) chemically synthesized nanoparticles using NaBH4 and PVP as reducing and stabilizing agents, respectively. Chemically synthesized AgNPs had been synthesized using different chemical methods and tested for their antibacterial potential however, no report is available on their mosquito larvicidal potential. Therefore, in the present study their effect would be evaluated in selected mosquito vectors.Chemical methods are usually employed for nanoparticles synthesis at industrial level which involves the use of toxic reducing and capping agents for synthesis thus limiting their use in biomedical applications due to risk of health hazard. Therefore, recently the interest is shiftedtowards utilizing potential of biological agents (plants, bacteria, fungi etc.) for nanoparticles   production. 

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