• Singh, Vineeta
• Pande, Veena
• Kamaraju, Raghavendra
• Moukoko, Carole Else Eboumbou
• Kedi, Philippe Belle Ebanda
• Verma, Vaishali
• Foko, Loick Pradel Kojom

Abstract

<jats:p><jats:bold>Purpose:</jats:bold> The recent emergence of <jats:italic>Plasmodium falciparum</jats:italic> (<jats:italic>Pf</jats:italic>) parasites resistant to current artemisinin-based combination therapies in Africa justifies the need to develop new strategies for successful malaria control. We synthesized, characterized and evaluated medical applications of optimized silver nanoparticles using <jats:italic>Alchornea cordifolia</jats:italic> (AC-AgNPs), a plant largely used in African and Asian traditional medicine.</jats:p><jats:p><jats:bold>Methods:</jats:bold> Fresh leaves of <jats:italic>A. cordifolia</jats:italic> were used to prepare aqueous crude extract, which was mixed with silver nitrate for AC-AgNPs synthesis and optimization. The optimized AC-AgNPs were characterized using several techniques including ultraviolet-visible spectrophotometry (UV-Vis), scanning/transmission electron microscopy (SEM/TEM), powder X-ray diffraction (PXRD), selected area electron diffraction (SAED), energy dispersive X-ray spectroscopy (EDX), Fourier transformed infrared spectroscopy (FTIR), dynamic light scattering (DLS) and Zeta potential. Thereafter, AC-AgNPs were evaluated for their hemocompatibility and antiplasmodial activity against <jats:italic>Pf</jats:italic> malaria strains 3D7 and RKL9. Finally, lethal activity of AC-AgNPs was assessed against mosquito larvae of <jats:italic>Anopheles stephensi</jats:italic>, <jats:italic>Culex quinquefasciatus</jats:italic> and <jats:italic>Aedes aegypti</jats:italic> which are vectors of neglected diseases such as dengue, filariasis and chikungunya.</jats:p><jats:p><jats:bold>Results:</jats:bold> The AC-AgNPs were mostly spheroidal, polycrystalline (84.13%), stable and polydispersed with size of 11.77 ± 5.57 nm. FTIR revealed the presence of several peaks corresponding to functional chemical groups characteristics of alkanoids, terpenoids, flavonoids, phenols, steroids, anthraquonones and saponins. The AC-AgNPs had a high antiplasmodial activity, with IC<jats:sub>50</jats:sub> of 8.05 μg/mL and 10.31 μg/mL against 3D7 and RKL9 <jats:italic>Plasmodium falciparum</jats:italic> strains. Likewise, high larvicidal activity of AC-AgNPs was found after 24 h- and 48 h-exposure: LC<jats:sub>50</jats:sub> = 18.41 μg/mL and 8.97 μg/mL (<jats:italic>Culex quinquefasciatus</jats:italic>), LC<jats:sub>50</jats:sub> = 16.71 μg/mL and 7.52 μg/mL (<jats:italic>Aedes aegypti</jats:italic>) and LC<jats:sub>50</jats:sub> = 10.67 μg/mL and 5.85 μg/mL (<jats:italic>Anopheles stephensi</jats:italic>). The AC-AgNPs were highly hemocompatible (HC<jats:sub>50</jats:sub> &amp;gt; 500 μg/mL).</jats:p><jats:p><jats:bold>Conclusion:</jats:bold> In worrying context of resistance of parasite and mosquitoes, green nanotechnologies using plants could be a cutting-edge alternative for drug/insecticide discovery and development.</jats:p>

Topics

• nanoparticle
• silver
• scanning electron microscopy
• electron diffraction
• powder X-ray diffraction
• transmission electron microscopy
• Energy-dispersive X-ray spectroscopy
• dynamic light scattering
• infrared spectroscopy
• liquid chromatography
• spectrophotometry
• ion chromatography