|Year : 2019 | Volume
| Issue : 1 | Page : 69-72
Larvicidal activity of chemically synthesized silver nanoparticles against Anopheles stephensi
Mahmoud Osanloo1, Seyed Mohammad Amini2, Mohammad Mehdi Sedaghat3, Amir Amani4
1 Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
2 Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences; Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, Iran
3 Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
4 Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences; Medical Biomaterials Research Center, Tehran University of Medical Sciences, Tehran, Iran
|Date of Web Publication||22-Aug-2019|
Department of Medical Nanotechnology, Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: Silver nanoparticles (AgNPs) have wide applications in different fields such as medicine, food industry, and pest management. Larvicidal activity of many herbally biosynthesized AgNPs have been evaluated against main malaria vector, that is, Anopheles stephensi. However, results of the studies are very different. No report has been found on larvicidal activity of chemically synthesized AgNPs against A. stephensi. Materials and Methods: AgNPs were synthesized using chemical reduction and characterized by dynamic light scattering and transmission electron microscopy. Concentration of silver ion in the final solution was determined by ICP-AES. Turbidity of solutions of AgNPs at different concentrations (i.e., 0.2–100 ppm) was studied. Subsequently, larvicidal activity of nanoparticles was evaluated, in line with the WHO guideline for laboratory tests. Results: AgNPs were synthesized successfully and confirmed by ultraviolet analysis. Nanoparticles were spherical with a diameter of ~30 nm. AgNPs had no larvicidal activity up to 80 ppm and showed a small larvicidal effect (~20%) at 100 ppm. Conclusion: Chemically synthesized AgNPs are not proper candidates for control of larvae due to their low efficacy and effects on nontarget specious lived in stagnant water.
Keywords: Chemical reduction, larvicidal activity and Anopheles stephensi, silver nanoparticles, silver nitrate, sodium borohydride
|How to cite this article:|
Osanloo M, Amini SM, Sedaghat MM, Amani A. Larvicidal activity of chemically synthesized silver nanoparticles against Anopheles stephensi. J Pharm Negative Results 2019;10:69-72
|How to cite this URL:|
Osanloo M, Amini SM, Sedaghat MM, Amani A. Larvicidal activity of chemically synthesized silver nanoparticles against Anopheles stephensi. J Pharm Negative Results [serial online] 2019 [cited 2020 Jul 2];10:69-72. Available from: http://www.pnrjournal.com/text.asp?2019/10/1/69/239961
| Introduction|| |
Silver nanoparticles (AgNPs) are being increasingly used in various fields including medical sciences, health care, food industry, and also heavy metal absorbents. Furthermore, biological activity of herbally biosynthesized AgNPs such as antioxidant  and hypoglycemic effect have been investigated. Recently, larvicidal activity of herbally biosynthesized AgNPs has been evaluated against many mosquito populations such as Aedes,Culex, and Anopheles. Among the mentioned mosquitoes, Anopheles stephensi is one of the main malaria vectors, thus, very important in public health, causing annually 500,000 death around the world.
In the literature, various values have been reported for lethal concentration (LC50) of AgNPs which have been biosynthesized, against A. stephensi, ranging from 0.5 to 37.7 ppm, showing a substantial difference (~75 times) in efficacy against larvae. However, there is no report about evaluation of larvicidal activity of pure AgNPs, which is synthesized with chemical reduction agents, against A. stephensi.
In this study, AgNPs were synthesized using silver nitrate and sodium borohydride (chemical reducer). First, larvicidal activity of sodium borohydride at applied concentration (40 mM) evaluated against A. stephensi. Then, larvicidal activity of AgNPs in range of 0.23–100 ppm was investigated.
| Materials and Methods|| |
Silver nitrate (AgNO3, 99%) was obtained from Dr. Mojallali Chemicals Co. (Iran). Sodium borohydride (NaBH4, 99%), nitric acid (reagent grade, 65%), and hydrochloric acid (ACS reagent, 37%) were purchased from Merck Chemicals (Germany). Glassware were washed with Aqua regia and rinsed with deionized (DI) water. All aqueous solutions were prepared with DI water (Barnsted E-Pure TM 18.3 MΩ water). A. stephensi (Beach strain) third and fourth instars larvae were used in this study, obtained from the Department of Medical Entomology, Tehran University Medical Sciences. Colonies were maintained at 28°C ± 2°C with 12:12 light and dark photoperiods and 65% ± 5% relative humidity.
Synthesis of silver nanoparticles
AgNPs were synthesized based on the chemical reduction route. Briefly, 0.5 mL of ice-cooled sodium borohydride solution (40 mM) was injected in 12 mL of silver nitrate solution (0.5 mM) under vigorous stirring for 15 min. Prepared AgNPs were concentrated through sequences of centrifugation at 3000 rpm for 4 min with 100 kDa centrifugation filter tube.
Characterization of silver nanoparticles
Particle size and particle size distribution of AgNPs were determined by dynamic light scattering (DLS, Scatteroscope, K-ONE. LTD, Korea). D50 (median) was taken as particle size and particle size distribution was calculated using the equation (1).
AgNPs were also studied by transmission electron microscopy (TEM, Zeiss EM 900 Germany). TEM pictures were analyzed by Digimizer software (MedCalc Software bvba, Belgium).
The exact concentration of silver ions was investigated by inductively coupled plasma atomic emission spectroscopy (ICP-AES, VISTA-PRO, Varian, USA). For confirming the successful synthesis of AgNPs, an extinction spectrum of the colloidal solution of nanoparticles was recorded by using a Lambda 35 (Perkin-Elmer USA) spectrophotometer.
Turbidity of solution of AgNPs was measured using Turbidimeter (2100AN Laboratory Turbidimeter, EPA, 115 Vac, USA).
Evaluation larvicidal activity of silver nanoparticles
Larvicidal activity of AgNPs was evaluated with the WHO guideline for laboratory test with some modifications. Solution of AgNPs with concentration of 100 ppm was employed as stock solution. By dilution of stock solution with DI water, different concentrations of AgNPs were prepared (i.e., 0.23–100 ppm). Batches of 25 larvae were added to containers containing 200 mL AgNPs at mentioned concentrations. The tests were repeated 16 times at 4 different replications. Two control groups were also considered: sodium borohydride (40 mM) and DI water. After 24 h of exposure, all larvae (live or dead) were transferred to distilled water using a textile filter and then dead larvae were counted.
| Results|| |
Characterization of silver nanoparticles
As shown in [Figure 1], synthesized AgNPs exhibit a sharp extinction peak at 390 nm, concluded successfully of synthesis process. Using DLS analysis, particle size and particle size distribution of AgNPs were 35 nm and 2 nm, respectively [Figure 2]. AgNPs had spherical shapes with size of 29 ± 4.5 nm, using TEM image [Figure 2].
|Figure 1: Dynamic light scattering (left) and transmission electron microscopy (right) images of silver nanoparticles. Determined particle sizes were 35.0 nm and 29.0 nm ± 4.5 nm, respectively|
Click here to view
Evaluation of larvicidal activity of silver nanoparticles
Turbidity of solutions of AgNPs at different concentrations and their corresponded larvicidal activity against A. stephensi are shown in [Table 1]. Turbidity decreased from 1040 nephelometric turbidity units (NTU) at concentration of 100 ppm, to 2.23 NTU, for sample with concentration of 0.23 ppm. No larvicidal activity was shown for different concentrations of AgNPs up to 80 ppm, and also, for sodium borohydride (40 mM) (data not shown). At concentration of 100 ppm, 21% mortality was observed. Higher concentrations of AgNPs were not tested due to production of high viscosity and osmotic pressure as well as the need to using chemical stabilizers.
|Table 1: Larvicidal activity of silver nanoparticles against Anopheles stephensi and related turbidity at different concentrations|
Click here to view
| Discussion|| |
Results of characterization of synthesized AgNPs are illustrated in [Figure 1] and [Figure 2]. Synthesized AgNPs had a sharp extinction peak at 390 nm, this value is comparable with recent reports: reported ranges of extinction peak for AgNPs were 390–420 nm.,, Results of TEM analysis show that they have spherical shape, with an average size of 29.3 ± 4.5 nm, showing appropriate particle size distribution.
Toxicity of chemically synthesized AgNPs for humans and animals has already been evaluated. For instance, toxicity of AgNPs with size of 35 nm appeared at 500 ppm in hepatocytes and at 1000 ppm in Caco-2 cells., In another study, after oral administration of AgNPs (60 nm, 1000 mg/kg/day) to Sprague Dawley Rats, liver toxicity was observed. Thus, in this study, larvicidal activity of AgNPs was investigated at below of toxic concentration, that is, in range of 0.2–100 ppm.
Reviewing the literature, many reports may be found about evaluation of larvicidal activity of herbally biosynthesized AgNPs against A. stephensi. In the followings, larvicidal activity of herbally biosynthesized AgNPs is classified by their size: LC50 of AgNPs with size <35 nm were 4.60, 19.13, and 28.22 ppm for nanoparticles biosynthesized by Ulva lactuca,Murraya koenigii, and Nerium oleander, respectively. Calculated LC50 for AgNPs in range of 35–60 nm were as 8.21, 4.98, and 21.51 ppm, for biosynthesized ones from Aristolochia indica,Aloe vera, and Euphorbia hirta, respectively. Furthermore, reported LC50 for AgNPs with sizes >60 nm were 15.28, 26.35, and 1.39 ppm, for the ones biosynthesized by materials extracted from Annona muricata,Cassia roxburghii, and Musa paradisiaca, respectively.
Considering the abovementioned reported, size does not appear to be important in determining the larvicidal activity of AgNPs. In two different studies on larvicidal activity of AgNPs with similar sizes (i.e., ~105 nm) reported LC50 values were substantially different, while LC50 of AgNPs biosynthesized by Plumeria rubra against A. stephensi was 1.74 ppm, corresponding value for AgNPs biosynthesized by A. muricata was documented as 37.7 ppm. A second factor which may contribute to the larvicidal activity of biosynthesized AgNPs is the activity of plant extract itself. However, LC50 of two different AgNPs which were biosynthesized with E. hirta and Plumeria rubra showed similar LC50 values (i.e., 169 and 171 ppm, respectively) while the LC50 of the extracts were hugely different (i.e., 21.51 and 1.74 ppm, respectively)., It is now well known that AgNPs easily interact with live organs, functional groups, or even other particles. Considering the mentioned reports and results of our work, it is arguable that larvicidal activity of AgNPs is related to functional groups on the surface of the nanoparticles which are formed during the biosynthesis process. Thus, the chemically synthesized nanoparticles which do not have surface groups are not expected to show larvicidal activity, a finding which has not been reported so far.
Besides that, increase in AgNPs concentration makes the water turbid [Table 1]. High turbidity could affect other nontarget organisms such as larvae of diving beetle or bacteria in stagnant water., This item greatly reduces usability of chemically synthesized AgNPs as larvicide.
Evaluation of larvicidal activity of herbally biosynthesized AgNPs is not limited to A. stephensi. Its larvicidal activity has been evaluated against other species of mosquitos such as Aedes aegypti,Culex quinquefasciatus, and Anopheles subpictus. Such activities may also be investigated for chemically synthesized AgNPs, in the future researches.
| Conclusion|| |
Although herbally biosynthesized AgNPs have shown various degrees of larvicidal activities, chemically synthesized AgNPs do not show toxicities against larvae of A. Stephensi. This could be due to lack of functional groups on the surface of prepared particles.
This research was supported by Tehran University of Medical Sciences and Health Services grant No. 95-01-87-31860.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Zhang XF, Liu ZG, Shen W, Gurunathan S. Silver nanoparticles: Synthesis, characterization, properties, applications, and therapeutic approaches. Int J Mol Sci 2016;17. pii: E1534.
Amini SM, Gilaki M, Karchani M. Safety of nanotechnology in food industries. Electron Physician 2014;6:962-8.
Shirkhanloo H, Osanloo M, Ghazaghi M, Hassani H. Validation of a new and cost-effective method for mercury vapor removal based on silver nanoparticles coating on micro glassy balls. Atmos Pollut Res 2017;8:359-65.
Madhanraj R, Eyini M, Balaji P. Antioxidant assay of gold and silver nanoparticles from edible basidiomycetes mushroom fungi. Free Radic Res 2017;7:137-42.
Shanker K, Mohan GK, Hussain MA, Jayarambabu N, Pravallika PL. Green biosynthesis, characterization,In vitro
antidiabetic activity, and investigational acute toxicity studies of some herbal-mediated silver nanoparticles on animal models. Pharmacogn Mag 2017;13:188-92.
Muthukumaran U, Govindarajan M, Rajeswary M. Green synthesis of silver nanoparticles from Cassia roxburghii
-a most potent power for mosquito control. Parasitol Res 2015;114:4385-95.
Santhosh SB, Ragavendran C, Natarajan D. Spectral and HRTEM analyses of Annona muricata
leaf extract mediated silver nanoparticles and its larvicidal efficacy against three mosquito vectors Anopheles stephensi
, Culex quinquefasciatus
, and Aedes aegypti
. J Photochem Photobiol B 2015;153:184-90.
Murugan K, Samidoss CM, Panneerselvam C, Higuchi A, Roni M, Suresh U, et al.
Seaweed-synthesized silver nanoparticles: An eco-friendly tool in the fight against Plasmodium falciparum
and its vector Anopheles stephensi
? Parasitol Res 2015;114:4087-97.
Arjunan NK, Murugan K, Rejeeth C, Madhiyazhagan P, Barnard DR. Green synthesis of silver nanoparticles for the control of mosquito vectors of malaria, filariasis, and dengue. Vector Borne Zoonotic Dis 2012;12:262-8.
World Health Organization. Who Guidelines for Laboratory and Field Testing of Mosquito Larvicides. World Health Organization; 2005. Available from: http://apps.who.int/iris/handle/10665/69101
. [Last accessed on 2018 Mar 06].
Agnihotri S, Mukherji S, Mukherji S. Size-controlled silver nanoparticles synthesized over the range 5-100 nm using the same protocol and their antibacterial efficacy. RSC Adv 2014;4:3974-83.
Guzmán MG, Dille J, Godet S. Synthesis of silver nanoparticles by chemical reduction method and their antibacterial activity. Int J Chem Biomol Eng 2009;2:104-11.
Mulfinger L, Solomon SD, Bahadory M, Jeyarajasingam AV, Rutkowsky SA, Boritz C. Synthesis and study of silver nanoparticles. J Chem Educ 2007;84:322.
de Lima R, Seabra AB, Durán N. Silver nanoparticles: A brief review of cytotoxicity and genotoxicity of chemically and biogenically synthesized nanoparticles. J Appl Toxicol 2012;32:867-79.
Gaiser BK, Fernandes TF, Jepson MA, Lead JR, Tyler CR, Baalousha M, et al.
Interspecies comparisons on the uptake and toxicity of silver and cerium dioxide nanoparticles. Environ Toxicol Chem 2012;31:144-54.
Kim YS, Kim JS, Cho HS, Rha DS, Kim JM, Park JD, et al.
Twenty-eight-day oral toxicity, genotoxicity, and gender-related tissue distribution of silver nanoparticles in Sprague-Dawley rats. Inhal Toxicol 2008;20:575-83.
Suganya A, Murugan K, Kovendan K, Mahesh Kumar P, Hwang JS. Green synthesis of silver nanoparticles using Murraya koenigii
leaf extract against Anopheles stephensi
and Aedes aegypti
. Parasitol Res 2013;112:1385-97.
Roni M, Murugan K, Panneerselvam C, Subramaniam J, Hwang JS. Evaluation of leaf aqueous extract and synthesized silver nanoparticles using Nerium oleander
against Anopheles stephensi
(Diptera: Culicidae). Parasitol Res 2013;112:981-90.
Murugan K, Labeeba MA, Panneerselvam C, Dinesh D, Suresh U, Subramaniam J, et al. Aristolochia indica
green-synthesized silver nanoparticles: A sustainable control tool against the malaria vector Anopheles stephensi
? Res Vet Sci 2015;102:127-35.
Dinesh D, Murugan K, Madhiyazhagan P, Panneerselvam C, Kumar PM, Nicoletti M, et al.
Mosquitocidal and antibacterial activity of green-synthesized silver nanoparticles from Aloe vera
extracts: Towards an effective tool against the malaria vector Anopheles stephensi
? Parasitol Res 2015;114:1519-29.
Priyadarshini KA, Murugan K, Panneerselvam C, Ponarulselvam S, Hwang JS, Nicoletti M, et al.
Biolarvicidal and pupicidal potential of silver nanoparticles synthesized using Euphorbia hirta
against Anopheles stephensi
liston (Diptera: Culicidae). Parasitol Res 2012;111:997-1006.
Jayaseelan C, Rahuman AA, Rajakumar G, Santhoshkumar T, Kirthi AV, Marimuthu S, et al.
Efficacy of plant-mediated synthesized silver nanoparticles against hematophagous parasites. Parasitol Res 2012;111:921-33.
Patil CD, Patil SV, Borase HP, Salunke BK, Salunkhe RB. Larvicidal activity of silver nanoparticles synthesized using plumeria rubra plant latex against Aedes aegypti
and Anopheles stephensi
. Parasitol Res 2012;110:1815-22.
Mavani K, Shah M. Synthesis of silver nanoparticles by using sodium borohydride as a reducing agent. Int J Eng Res Technol 2013;2:1-5.
Zamxaka M, Pironcheva G, Muyima N. Microbiological and physico-chemical assessment of the quality of domestic water sources in selected rural communities of the Eastern Cape Province, South Africa. Water Sa 2004;30:333-40.
Mulla MS, Federici BA, Darwazeh HA. Larvicidal efficacy of Bacillus thuringiensis
serotype H-14 against stagnant-water mosquitoes and its effects on nontarget organisms. Environ Entomol 1982;11:788-95.
Deepak P, Sowmiya R, Ramkumar R, Balasubramani G, Aiswarya D, Perumal P, et al.
Structural characterization and evaluation of mosquito-larvicidal property of silver nanoparticles synthesized from the seaweed, Turbinaria ornata
(Turner) J. Agardh 1848. Artif Cells Nanomed Biotechnol 2017;45:990-8.
Suman TY, Rajasree SR, Jayaseelan C, Mary RR, Gayathri S, Aranganathan L, et al.
GC-MS analysis of bioactive components and biosynthesis of silver nanoparticles using Hybanthus enneaspermus
at room temperature evaluation of their stability and its larvicidal activity. Environ Sci Pollut Res Int 2016;23:2705-14.
[Figure 1], [Figure 2]