Ionic liquid functionalized biogenic synthesis of AgAu bimetal doped CeO(2) nanoparticles from Justicia adhatoda for pharmaceutical applications: Antibacterial and anti-cancer activities.

The noble metal such as Ag and Au doped CeO2 nanoparticles was successfully prepared by ionic liquid assisted hydrothermal method in the presence of Justicia adhatoda leaves extract and were used as an antibacterial and anticancer agent. The FT-IR and Raman spectrum exhibit the peaks at 460 and 464 cm-1 assigned to CeO stretching vibrations of NPs. The electron microscopic micrographs confirmed the spherical shaped morphology of prepared NPs. The insertion of Ag and Au ions into the CeO2 surface creates lattice defects the leads to reduce the band gap energy of Ag-Au/CeO2 at 3.15 eV. The XRD results suggested the average crystalline size of the silver‑gold loaded CeO2 was 28 nm. From the elemental mapping images, we have visualized that existence and uniform distribution of Ag, Au, Ce, and O in the prepared nanomaterials. The antibacterial activity of unloaded and bimetal loaded CeO2 NPs was evaluated with Gram-positive and Gram-negative bacteria using disc diffusion assay. The AgAu loaded CeO2 NPs exhibited the highest zone of inhibition against E. coli and S. aureus strains when compared with pristine CeO2, Ag loaded CeO2, and Au loaded CeO2 NPs. In addition, the 100 μg mL-1 of CeO2, Ag/CeO2, Au/CeO2 and Ag-Au/CeO2 NPs exposed the 50, 51, 52 and 56% of anticancer activity against the HeLa cells respectively. Overall, this study concludes that the ionic liquid functionalized green synthesized bimetal loaded cerium oxide NPs showed potent antibacterial and anticancer activities.

Nithya P ，Sundrarajan M 《-》

Ionic liquid - A greener templating agent with Justicia adhatoda plant extract assisted green synthesis of morphologically improved Ag-Au/ZnO nanostructure and it's antibacterial and anticancer activities.

Metal and metal oxide nanoparticles (NPs) possess significant properties that are promising materials for biological applications. In this research work, we prepared ionic liquid assisted Ag-Au/ZnO NPs, using J.adhatoda leaves extract by hydrothermal method. Ionic liquids performed as a stabilizing and templating agent to improve the surface morphology of the synthesized Ag and Au doped ZnO NPs. The prepared ZnO, Ag-doped ZnO, Au doped ZnO, and AgAu doped ZnO NPs exhibit the average crystalline size of 36, 34, 32, and 25 nm and their band gap energy values are 3.36, 3.29, 3.17, and 2.98 eV respectively. The XRD and UV-DRS result shows that after doping of Au and Ag the ZnO crystalline size and band gap energy was decreased, which leads to enhanced the biomedical (antibacterial and anticancer) properties of AgAu doped ZnO NPs. The Raman active mode of A1 (LO) and A1 (TO) showed that the formation of lattice defects due to the Ag and Au doping in the ZnO crystalline plane to improve the Ag-Au/ZnO properties. SEM and TEM images revealed that the prepared AgAu doped ZnO NPs exhibits nano stick shape with particle size range from 20 to 25 nm. The EDX spectrum and elemental mapping results confirmed that Ag and Au atoms are doped and spread over the ZnO NPs. The corresponding SAED pattern also confirms the crystallinity of Ag-Au/ZnO NPs. Furthermore, the synthesized Ag-Au/ZnO NPs has been explored for its antibacterial and anticancer activities. It shows good antibacterial activity against E.coli and S.aureus bacteria. Additionally, the Ag-Au/ZnO NPs show excellent anticancer activity against the HeLa cancer cells. The excellent antibacterial and anticancer results prove that the bi-metal (Ag and Au) doping can enhance the biomedical properties of ZnO NPs. It will be a promising material in the biomedical field.

Pandiyan N ，Murugesan B ，Arumugam M ，Sonamuthu J ，Samayanan S ，Mahalingam S ... -  《-》

Facile biological synthetic strategy to morphologically aligned CeO(2)/ZrO(2) core nanoparticles using Justicia adhatoda extract and ionic liquid: Enhancement of its bio-medical properties.

In this study, a typical green synthesis route has approached for CeO2/ZrO2 core metal oxide nanoparticles using ionic liquid mediated Justicia adhatoda extract. This synthesis method is carried out at simple room temperature condition to obtain the core metal oxide nanoparticles. XRD, SEM and TEM studies employed to study the crystalline and surface morphological properties under nucleation, growth, and aggregation processes. CeO2/ZrO2 core metal oxides display agglomerated nano stick-like structure with 20-45nm size. GC-MS spectroscopy confirms the presence of vasicinone and N,N-Dimethylglycine present in the plant extract, which are capable of converting the corresponding metal ion precursor to CeO2/ZrO2 core metal oxide nanoparticles. In FTIR, the corresponding stretching for Ce-O and Zr-O bands indicated at 498 and 416cm-1 and Raman spectroscopy also supports typical stretching frequencies at 463 and 160cm-1. Band gap energy of the CeO2/ZrO2 core metal oxide is 3.37eV calculated from UV- DRS spectroscopy. The anti-bacterial studies performed against a set of bacterial strains the result showed that core metal oxide nanoparticles more susceptible to gram-positive (G+) bacteria than gram-negative (G-) bacteria. A unique feature of the antioxidant behaviors core metal oxides reduces the concentration of DPPH radical up to 89%. The CeO2/ZrO2 core metal oxide nanoparticles control the S. marcescent bio-film formation and restrict the quorum sensing. The toxicology behavior of CeO2/ZrO2 core metal oxide NPs is found due to the high oxygen site vacancies, ROS formation, smallest particle size and higher surface area. This type of green synthesis route may efficient and the core metal oxide nanoparticles will possess a good bio-medical agent in future.

Pandiyan N ，Murugesan B ，Sonamuthu J ，Samayanan S ，Mahalingam S ... -  《-》

Biosynthesis of silver and gold nanoparticles using Musa acuminata colla flower and its pharmaceutical activity against bacteria and anticancer efficacy.

Synthesis of nanoparticles using plant sources as reducing agent has become important, as physical and chemical methods are costlier and affects environment. Hence it is important to develop environment friendly nanoparticle synthesis by avoiding the use of toxic chemicals. The present study aimed to synthesize silver nanoparticles (Ag Nps) and gold nanoparticles (AuNps) using Musa acuminata colla flower and its pharmaceutical activity against extended spectrum beta-lactamase (ESBL) gene producing bacteria and anticancer efficacy. The synthesized Ag and Au NPs were analysed by means of UV-Vis, FTIR, XRD,SEM and EDAX evidenced the bioreduction of Ag+ ions to Ag0 and Au3+ ions to Au0 respectively. Both nanoparticles and flower extracts were studied for antibacterial activity of ESBL gene producing bacteria by disc diffusion and microdilution (Resazurin) method. In vitro anticancer efficacy (MCF-7) and toxicity (VERO) of AgNPs, AuNPs, aqueous extract and ethanol extract of flowers were performed by MTT assay. IC50 value for DPPH analysis was at 390 μg and 460 μg for ethanol and aqueous extract respectively. Total antioxidant content was found be 740 μg/mg and 460 μg/mg for ethanol and aqueous extract. GCMS analysis authenticated the existence of the compounds namely, 9,12-octadecadienoic acid(z,z)- and n-hexadecanoic acid in the crude extract of the samples. Among the samples, AgNPs had best antibacterial activity. AgNPs and AuNPs were confirmed by colour change to reddish brown and ruby red. Further ƛmax were obtained at 474 and 540 nm by UV - visible spectrum. SEM analysis revealed the particle size ranges from 12.6 to 15.7 nm for silver and 10.1 to 15.6 nm for gold nanoparticles. The EDAX spectrum shows a strong signal for elemental Ag and Au at ~ 3 keV and 1.5 keV. The XRD patterns for silver and gold nanoparticles at 36.701, 42.900, 63.281 and 76.398 corresponding to the lattice planes 2.4467, 2.1064, 1.46839, 1.24564 nm and 27.32, 36.7228, 39.56, 42.888, 63.253, 63.253, 65.02 and 76.383 corresponding to the lattice planes 3.262, 2.44530, 2.276, 2.1070, 1.46897, 1.4332 and 1.24585 nm. The IC50 values for MCF-7 and VERO cells were 30.0 μg/ml and 55.0 μg/ml respectively.

Valsalam S ，Agastian P ，Esmail GA ，Ghilan AM ，Al-Dhabi NA ，Arasu MV ... -  《-》

Green chemical approach towards the synthesis of CeO(2) doped with seashell and its bacterial applications intermediated with fruit extracts.

Nanomaterials of CeO2 with A. vera were synthesized by using simple chemical method. Grapes drops are used as an oxidizing agent. Structural and morphological studies of nanomaterials of cerium oxide (CeO2), were studied for combustion method of preparation. The precursor solution was initialized by a hydrothermal reaction. Cerium hydroxyl carbonate precursors which involves cerium (III) nitrate Ce(NO3)3. 6 H2O with (1.0M) of seashell powder, 3% A. vera, extracts, grapes and pomegranate drops and this complex solution was used to produce the CeO2 powder particles. We have prepared another sample with 5% of Aloe vera extract and found that 3% Aloe vera extract has lesser grain size and enhanced band gap values, so the article explained the sample analysis of combination with 3% extract of Aloe vera. The product has the rod pattern which was the unusual features appear to originate from the unique crystal chemistry aspects. From the optical absorption spectrum, it has been shown that the CeO2 rods have 3.847eV of direct band gap energy. The minimum inhibitory concentration (MIC) values of the synthesized compounds exhibited activity towards various microbial pathogens such as B. subtilis (15μg/mL), S. aureus (50μg/mL), S. epidermidis (20μg/mL), E. faecalis (25μg/mL) and towards E. coli (100μg/mL), K. pneumoniae (50μg/mL) and P. aeruginosa (75μg/mL) respectively. The tests on bacterial activities confirmed that the CeO2 rods are suitable hand for the biological applications. The seashell structure and the phytochemical contents of A. vera might enhance its bacterial activities.

Arasu MV ，Thirumamagal R ，Srinivasan MP ，Al-Dhabi NA ，Ayeshamariam A ，Saravana Kumar D ，Punithavelan N ，Jayachandran M ... -  《-》