Green Synthesis of Silver Nanoparticles Using Panax Ginseng Root Extract for the Detection of Hg2+

Abstract

Exploring biomaterials/molecules as a reducing/capping agent for the synthesis of metal nanoparticles has set a new trend in green nanotechnology with improved environmental safety. Herein, a facile, one-pot, and green synthesis of silver nanoparticles (AgNPs) was achieved using Panax ginseng root extract that was obtained from the root powder as a cost-effective and environmentfriendly biomaterial. Optical, functional, and morphological characteristics of the synthesized AgNPs were determined using ultraviolet-visible (UV-vis), Fourier transform infrared (FTIR) spectrophotometers, transmission electron microscopy (TEM), and atomic force microscopy (AFM). The synthesized AgNPs were used for the detection of Hg 2+ by obtaining the absorption spectrum of the compound as a function of Hg 2+ concentration, which resulted in a decrease in absorption peak intensity with a slight blue shift. The AgNP solution decolored upon dissolution due to the formation of an Ag-Hg amalgam. The sensing characteristics were found to be linear when tested from 10 µM to 1 mM Hg 2+ concentration and the detection limit was estimated as 5 µM. To check the selectivity of the sensor towards Hg 2+ , the sensor response was measured for different heavy metals such as K + , Na + , Cu 2+ , Ni 2+ , Ca 2+ , Zn 2+ , Mg 2+ , and Mn 2+ , at 10 mM concentrations.

Trace Level Colorimetric Hg2+ Sensor Driven by Citrus japonica Leaf Extract Derived Silver Nanoparticles: Green Synthesis and Application

“…However the later pH was suitable and selected due to economical aspect. pH 8.0 or higher pH has been reported for formation of small sized AgNPs [23][24][25] and supports our findings. At acidic pH the poor nucleation of Ag ?…”

“…to Ag 0 and reveals the efficiency of Citrus japonica leaf extract as a suitable reducing and capping agent. Similar results have been reported for the synthesis of AgNPs using green synthetic process [23,24]. So, the LSPR band of AgNPs shifted from 408 to 407 when 250 lL volume of leaf extract was added.…”

“…The stable nature and Fig. 1 UV-Vis spectra of CJ-AgNPs recorded for time stability study from 5 min to 15 days kinetics of formation of CJ-AgNPs confirm that the cautious optimization of parameters make these NPs fairly important compared to those reported by other researchers [23][24][25][26].…”

“…Hence, 5 mM of AgNO 3 was selected as optimized concentration where CJ-AgNPs produced a strong LSPR band with minimum wavelength of 408 nm in the UV-Vis spectrum forming golden-yellow colored solution. Similar studies have also been carried out by other workers for the synthesis of AgNPs [23]. As CJ leaf extract is working as capping as well as reducing agent, therefore, its optimized volume is crucial for getting small sized AgNPs with increased catalytic properties and best stability of resulting solution.…”

“…Alkaline pH results in higher concentration of OHwhich facilitates the higher rate of AgNPs synthesis [26]. Tagad et al [23] have also reported the effect of pH on the synthesis of AgNPs and suggested that higher pH is always ideal for the formation of small and stable NPs.…”