Biosynthesis, Characterization, and Bioactivities Evaluation of Silver and Gold Nanoparticles Mediated by the Roots of Chinese Herbal Angelica pubescens Maxim

Abstract

A facile synthesis and biological applications of silver (DH-AgNps) and gold nanoparticles (DH-AuNps) mediated by the aqueous extract of Angelicae Pubescentis Radix (Du Huo) are explored. Du Huo is a medicinal root belonging to Angelica pubescens Maxim which possesses anti-inflammatory, analgesic, and antioxidant properties. The absorption spectra of nanoparticles in varying root extract and metal ion concentration, pH, reaction temperatures, and time were recorded by ultraviolet–visible (UV-Vis) spectroscopy. The presence of DH-AgNps and DH-AuNps was confirmed from the surface plasmon resonance intensified at ~414 and ~540 nm, respectively. Field emission transmission electron micrograph (FE-TEM) analysis revealed the formation of quasi-spherical DH-AgNps and spherical icosahedral DH-AuNps. These novel DH-AgNps and DH-AuNps maintained an average crystallite size of 12.48 and 7.44 nm, respectively. The biosynthesized DH-AgNps and DH-AuNps exhibited antioxidant activity against 2,2-diphenyl-1-picrylhydrzyl (DPPH) radicals and the former exhibited antimicrobial activity against clinical pathogens including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella enterica. The expected presence of flavonoids, sesquiterpenes, and phenols on the nanoparticle surface were conjectured to grant protection against aggregation and free radical scavenging activity. DH-AgNps and DH-AuNps were further investigated for their cytotoxic properties in RAW264.7 macrophages for their potential application as drug carriers to sites of inflammation. In conclusion, this green synthesis is favorable for the advancement of plant mediated nano-carriers in drug delivery systems, cancer diagnostic, and medical imaging.Graphical abstractSchematic diagram of biosynthesis of DH-AgNps and DH-AuNps and evaluation of their bioactivities.

Biosynthesized gold and silver nanoparticles by aqueous fruit extract of Chaenomeles sinensis and screening of their biomedical activities

“…Similarly, XRD spectra of Cs-AuNps (Figure 2(b)) and Cs-AgNps (Figure 2(e)) demonstrated identical diffraction peaks. Multiple negligible diffraction peaks in Figure 2(e) were present indicating the formation of bio-organic impurities in Cs-AgNps [5]. No artificial diffraction peaks due to crystallographic impurities were evident in Cs-AuNps, indicating pure gold metal.…”

“…malic acid, tartaric acid, limonin, vitamin C, tannin), which are the major phytochemicals of C. sinensis fruit [2][3][4]. Bioreduction methods based on plants [1,5,6], fungi [7] and bacteria [8] are more benefiting as the usage of harmless solvent, non-toxic reducing agents and ecofriendly materials reduce the risks of biomedical applications.…”

The Chemical Compositions of Angelica pubescens Oil and Its Prevention of UV‐B Radiation‐Induced Cutaneous Photoaging

“…Recent studies have shown that AO contains antioxidants that can catalyze ROS into O 2 and H 2 O. [ ][ ] Hence, AO possesses both antioxidant and anti‐inflammatory effects, which are crucial to its anti‐photoaging effect.…”

Biosynthesis, characterisation and therapeutic applications of plant-mediated silver nanoparticles

“…The average crystallite size was 12.48 nm. 48 Generally, by augmenting the concentration of AgNO 3 , the production of AgNPs increases 46 and the color of the solution intensifies, because aggregation of silver ions occurs and larger nanoparticles are obtained. 14 In the case of AgNPs from Solanum trilobatum using 1 mM AgNO 3 , monodisperse nanoparticles were formed without aggregation.…”