Biosynthesis of AgNPs using aqueous leaf extract of Ipomoea eriocarpa and their anti-inflammatory effect on carrageenan-induced paw edema in male Wistar rats

Silver nanoparticles (AgNPs) were synthesised from aqueous Ag nitrate through a simple, competent and eco-friendly method using the leaf extract of Ipomoea eriocarpa as reducing as well as capping agent. Ultraviolet-visible absorption spectroscopy was used to confirm the formation of AgNPs which displayed the substantiation of surface plasmon bands at 425nm. The NPs were also characterised using Fourier transformer infrared spectroscopy, X-ray diffraction method, transmission electron microscope and zeta potential. The characterisation study confirmed the formation of AgNPs, their spherical shape and average diameter of 12.85 +/- 8.65nm. Zeta potential value of -20.5mV suggested that the AgNPs are stable in the suspension. The aqueous extract and the AgNPs were further screened for in vivo anti-inflammatory activity using carrageenan-induced paw edema in male Wistar rats. The study demonstrated that the AgNPs (1mlkg(-1)) had a significant (p<0.05) anti-edemic effect and inhibition was observed from the first hour (21.31 +/- 1.34) until the sixth hour (52.67 +/- 1.41), when the inhibitory effect was greatest and superior to the aqueous extract and the standard, diclofenac.