Biological synergy of greener gold nanoparticles by using Coleus aromaticus leaf extract

• Published in: Materials Science & Engineering C 2019-06, Vol.99, p.202-210
• Main Authors: Boomi, P., Ganesan, R.M., Poorani, G., Gurumallesh Prabu, H., Ravikumar, S., Jeyakanthan, J.
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - pharmacology; Antibacterial activity; Anticancer properties; Antiinfectives and antibacterials; Antitumor agents; Au nanoparticles; Cell Death - drug effects; Chemical synthesis; Coleus; Coleus - chemistry; Coleus aromaticus; Cotton; Cotton fabrics; Cotton Fiber; Cytotoxicity; Diffuse reflectance spectroscopy; Dynamic Light Scattering; E coli; Fabrics; Fourier transforms; Functional groups; Gold; Gold - chemistry; Green Chemistry Technology - methods; Hep G2 Cells; Hepatocytes; Humans; Infrared analysis; Infrared spectroscopy; Inhibitory Concentration 50; Leaves; Light scattering; Liver; Liver cancer; Materials science; Medical treatment; Metal Nanoparticles - chemistry; Metal Nanoparticles - ultrastructure; Microbial Sensitivity Tests; Morphology; Nanoparticles; Nanotechnology; Organic chemistry; Photon correlation spectroscopy; Plant extracts; Plant Extracts - chemistry; Plant Leaves - chemistry; Resonance scattering; Scanning electron microscopy; Spectrophotometry, Ultraviolet; Spectroscopy; Spectroscopy, Fourier Transform Infrared; Spectrum analysis; Surface charge; Surface plasmon resonance; Surface stability; Toxicity; Transmission electron microscopy; Ultraviolet radiation; UV protection; Visual observation; X-Ray Diffraction; Zeta potential
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2019.01.105

Greener nanotechnology plays an important role in developing alternative and effective treatment strategies for various diseases. Biological synthesis of metal nanoparticles (MNPs) has known to possess suitable alternatives than the existing chemical methods. Greener synthesis of MNPs by using plant extracts has become an emerging field due to their safe, eco-friendly and non-toxic nature that are suitable for synergistic biological activities. Hence, the greener method is chosen by the present study. In the present study, the greener synthesis of gold nanoparticles (AuNPs) was successfully done by using Coleus aromaticus leaf extract at three different temperatures (30 °C, 60 °C and 100 °C). The formation of AuNPs was initially monitored by visual observation and then characterized with the help of diverse techniques like UV–Vis spectroscopy (UV–Vis), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), High Resolution-Transmission Electron Microscopy (HR-TEM) and dynamic light scattering (DLS). Surface plasmon resonance (SPR) peak and crystalline nature of AuNPs were obtained by UV–Vis and XRD spectroscopies respectively. FT-IR analysis shows the different characteristic functional groups in turn responsible for the bio-reduction of gold ions by using leaf extract. The formations of different nano-sized AuNPs with their different morphologies were observed by SEM and HR-TEM analyses. Surface charge and stability of the AuNPs were measured by zeta potential and DLS respectively. The synthesized AuNPs coated with cotton fabric was analyzed by UV-Diffuse Reflectance Spectroscopy (UV-DRS), which revealed excellent UV protection against UV radiation. The AuNPs coated cotton fabric exhibited remarkable antibacterial sensitivity against Staphylococcus epidermidis and Escherichia coli. Further, the synthesized AuNPs showed significant cytotoxicity against human liver cancer (HepG2) cell line. The findings of this study revealed that, AuNPs synthesized using Coleus aromaticus leaf extract could be an alternative, safe, and effective source of UV protection, antibacterial and anticancer agents. •AuNPs synthesis using Coleus aromaticus leaf extract•SPR, crystalline nature, functional groups and different nano sizes with morphology of AuNPs were obtained.•Remarkable UV blocking property was reported against UV radiation.•The remarkable antibacterial activity of AuNPs coated cotton fabric was obtained against b