GREEN SYNTHESIZED COPPER NANOPARTICLES AND THEIR ANTIBACTERIAL ACTIVITY - A REVIEW

Biogenic synthesis of diverse nanoparticles via greener path has gained interest by researchers as they are eco-friendly, sustainable, and non-toxic. Present review article aims to update diversified copper nanoparticle (CuNPs) synthesis and their antibacterial activity thru greener method using different plant parts like leaves, fruits and roots. The phytoconstituents present in the plants acts as stabilizing and bioreducing agent for the synthesis of CuNPs. Various reports are available on the synthesis of CuNPs using precursors like copper sulphate, copper acetate and copper nitrate with different sizes of CuNPs ranging from 1-200 nm with spherical, rod and hexagonal shapes. CuNPs exhibited significant inhibition of gram positive and gram negative bacteria. This review highlights the synthesis of CuNPs using different parts of plants and their potential applications as antibacterial agents, which may act as a promising drug candidate through nano approach

Antibacterial and anticancer potential of Brassica oleracea var acephala using biosynthesised copper nanoparticles

@#ary phytochemical screening. The resultsshowed that the ethanolic crude extract of the leaf containhigh phytochemical activity hence B.oleraceavaracephalais rich in flavonoids, phenolic compounds, carbohydratesand phytosterols. Materials and methods: The ethanolic extract was used tosynthesise copper nanoparticles. The copper nanoparticleswere successfully synthesised from copper sulphatesolution which was identified by the colour change fromdark green colour of the extract. Thus the B.oleracea varacephala is a good source to synthesis coppernanoparticles. The synthesised copper nanoparticles werecharacterised using Scanning Electron Microscope (SEM)analysis. The SEM image displayed the high-densitynanoparticles synthesised by leaf extracts and that thenanoparticles were crystals in shape. Results: The copper nanoparticles (CNP) bind to the leafextract. B.oleraceavaracephalaalso has shown theantimicrobial and antioxidant activity. A comparative studywas done between ethanolic its crude extract andnanoparticles. Both extracts exhibited zone of inhibition andbetter antioxidant potential but the CuNPs shows majorzone of inhibition and showed more antioxidant activity.Anticancer activity of B.oleraceavaracephalaagainstCervical HeLa cell line was confirmed using ethanolic crudeextract and CNP. The results showed that HeLa cellsproliferation was inhibited with increasing concentration ofethanolic crude extract and copper nanoparticles. From theresults, it was seen that percentage viability of the cancercells decreased with increased concentration of the sampleswhereas cytotoxicity against HeLa cell lines increased withthe increased concentration of the samples. Conclusion: Thus B.oleraceavaracephalapossessesanticancer activity against HeLa cell lines.

Formulation And Evaluation Of Copper Nanoparticles Loaded Microsponges

Microsponges become imperative in the field of targeted drug delivery and in other biomedical applications. There was a clamant need for designing microsponges incorporating with green synthesised metal nanoparticles rather than the chemical drug in order to reduce the side effects of the drug and thus increasing the effectiveness of nature of the whole material. It provokes us to design this novel approach of loading copper nanoparticles into the microsponges. Here in this work, microsponges based on ethyl cellulose and polyvinyl alcohol were synthesised by Quasi-Emulsion Solvent diffusion method in which copper nanoparticles procured from Hibiscus rosa-sinensis leaf extract was incorporated. The Loaded microsponges were characterised by High Resolution Scanning Electron Microscopy (HR-SEM) and Particle size distribution Analyzer (PSA). The Drug content and Entrapment Efficiency of the microsponges were found out. The antimicrobial and antioxidant activity of the loaded microsponges were evaluated.

Studies on Green Synthesis of Copper Nanoparticles Using Punica granatum

Aim: The present study aimed at green synthesis of copper nanoparticles using various plant extracts as reducing and stabilizing agents. It would also study the antibacterial effect of the synthesized copper nanoparticles. Place and Duration of Study: Department of Microbiology, Bhavan’s Vivekananda college of Science, Humanities and Commerce, Hyderabad, India. The duration of the study is for six months between May 2017 to October 2017. Methodology: The aqueous solutions of different plant extracts were mixed with CuSO4 solution and incubated for green synthesis of stable copper nanoparticles. These were tested by UV-Visible spectroscopy and SEM analysis. Antibacterial tests of the biosynthesized nanoparticles were carried out on Gram-positive Bacteria Staphylococcus aureus by Agar well assay. Results: The aqueous solutions of different plant extracts yielded stable copper nanoparticles as indicated by the O.D values tested using UV-Visible spectroscopy. The best plant extract that yielded higher amount of copper nanoparticles was fruit rind extract of Punica granatum. The synthesized nanoparticles were found to be 56-59 nm, characterized by Scanning Electron Microscopy (SEM). The synthesized copper nanoparticles exhibited a strong antibacterial activity against Staphylococcus aureus. Conclusion: The copper nanoparticles can be green synthesized using fruit rind extract of Punica granatum and these can be used as efficient antimicrobial agents against Staphylococcus aureus and the study is significant currently as drug resistant infections of Staphylococcus aureus are gaining much prevalence and prominence.

Preparación y Caracterización de Nanocompositos Quitosano-Cobre con Actividad Antibacteriana para aplicaciones en Ingeniería de Tejidos / Preparation and characterization of Copper Chitosan Nanocomposites with Antibacterial Activity for Applications in Tissue Engineering

RESUMEN: El presente trabajo describe la preparación de nanocompositos formulados a partir de quitosano (QS)/nanopartículas de cobre (nCu) con características antibacterianas y aplicación potencial en ingeniería de tejidos. Para ello, se prepararon nanocompositos mediante mezclado en solución asistido con ultrasonido con el objetivo de incrementar la dispersión de la carga nanométrica en el biopolímero. El análisis de FTIR demostró que la presencia de nCu en la matriz de QS favorece la interacción del nCu con los grupos amino/hidroxilo de la molécula del QS. Se determinó mediante UV-Vis que los nanocompositos QS/nCu presentan absorción asociada con la presencia de nanopartículas y la posible liberación de iones Cu2+ en medio líquido. Mediante AFM se determinó que el QS hidratado forma una malla con microporos, que puede favorecer la penetración de bacterias en el nanocomposito y su interacción con las nCu. Finalmente, se determinó el efecto antibacteriano del material al contacto con la bacteria Staphylococcus aureus, en donde se presenta una actividad antibacteriana superior al 90% entre los 90 y 180 min de interacción. Dichos resultados sugieren que es posible obtener nanomateriales antibacterianos biocompatibles para su posible aplicación en ingeniería tisular.

ABSTRACT: The Present work describes the preparation of nanocomposites based on chitosan (QS)/copper nanoparticles (nCu) with antibacterial properties and potential application in tissue engineering. For this purpose, nanocomposites were prepared by solution blending with ultrasound assisted, aiming to increase the nanoparticles dispersion in the biopolymer. FTIR analyses demonstrates that nCu supported in QS increase their interaction of nanoparticles with amine/hydroxyl groups of QS molecule. UV-Vis analyses demonstrates that QS/nCu nanocomposites have an absorption signal associated with the presence of nanoparticles and the possible Cu2+ ions release in liquid media. AFM analyses shown that hydrated QS form a mesh with micro pores, improving the bacterial penetration and the direct contact with nCu. This behavior was corroborated by antibacterial assays, where QS/nCu nanocomposites shown an antibacterial activity higher than 90% between 90-180 minutes of interaction. Our results suggest that is possible to obtain combined antibacterial/biocompatible nanomaterials with potential application in tissue engineering.

Copper nanoparticles as potential antimicrobial agent in disinfecting root canals: a systematic review / Nanopartículas de cobre como potencial agente antimicrobiano en la desinfección de canales radiculares: revisión sistemática

Copper was registered as the first solid antimicrobial material. Its availability makes it an important option as an antibacterial agent. At nanoparticle size it does not exceed 100 nm, allowing close interaction with microbial membranes, enhancing its effect even more. Copper generates toxic hydroxyl radicals that damage cell membranes of Gram-negative and Gram-positive bacteria, among the latter, Enterococcus faecalis, which are present in infected radicular canals. Synthesis of metal nanoparticles with antimicrobial properties has become a viable alternative and has promising applications in the fight against pathogenic microorganisms. Furthermore, the use of some polymers to stabilize nanoparticles increases their release time and may as well decrease the risk of bacterial recolonization and biofilm formation within the ducts, enhancing the antimicrobial properties of these compounds.The aim of this article is to conduct a systematic review of the literature on antimicrobial copper nanoparticles, their current applications and their potential use in the area of oral health, specifically in the field of endodontics.

El cobre fue registrado como el primer material antimicrobiano sólido y su disponibilidad permite que constituya una importante opción como agente antibacteriano. Al tamaño de nanopartícula no supera los 100 nm, lo que permite una interacción estrecha con las membranas microbianas, potenciando aún más su efecto. Genera radicales hidroxilos tóxicos que provocan daño en la membrana celular de bacterias Gram negativas y Gram positivas, entre estas últimas, Enterococcus faecalis, presente en conductos radiculares infectados. Por lo que la síntesis de nanopartículas metálicas con propiedades antimicrobianas se ha vuelto una alternativa viable con aplicaciones prometedoras en la lucha contra microorganismos patógenos. Además, utilizando algunos polímeros para estabilizar las nanopartículas se aumenta el tiempo de liberación de éstas y se disminuye el riesgo de recolonización bacteriana y la formación de biopelículas al interior de los conductos, mejorando las propiedades antimicrobianas de estos compuestos. El propósito de este artículo es realizar una revisión sistemática de la literatura acerca de nanopartículas de cobre como antimicrobiano, sus aplicaciones actuales y su potencial uso en el área de la salud oral, específicamente en el campo de la Endodoncia.

Actividad inhibitoria del crecimiento bacteriano por cobre nanoestructurado obtenido de minerales de la región Marañón: comparación con cobre comercial / Bacterial growth inhibitory activity for nanostructured copper minerals obtained from the Marañon region: comparison with commercial copper

En el presente trabajo se reporta la actividad inhibitoria del crecimiento bacteriano por nanopartículas de cobre cementado y de cobre comercial. Se utilizaron las cepas de Staphylococcus aureus ATCC 6538 (Gram positiva) y Escherichia coli ATCC 35218 (Gram negativa) para determinar el efecto inhibitorio mediante la concentración mínima inhibitoria de las nanopartículas diluidas en caldo de cultivo nutritivo y distribuidas en placas de ELISA. Las muestras de cobre cementado (obtenidas por procesos hidrometalúrgicos) y de cobre comercial fueron nanoestructuradas empleando un equipo de molienda mecánica. Los resultados indican que las nanopartículas de cobre comercial (a 2.5 horas de molienda) muestran acción inhibitoria del crecimiento de la cepa S. aureus y no así en la cepa E. coli. Asimismo, se determinó que la concentración mínima inhibitoria de la muestra de cobre comercial fue de 20 μg/mL frente a S. aureus. El cobre cementado (en su forma sólida y nanoestructurada) no mostró efecto inhibitorio del crecimiento en ninguna de las dos cepas estudiadas.

In this paper, we report on the bacterial growth inhibitory activity of nanoparticles of cemented and commercial copper. Strains of Staphylococcus aureus ATCC 6538 (Gram positive) and Escherichia coli ATCC 35218 (Gram negative) were used to determine the inhibitory effect by the minimal inhibitory concentration of the nanoparticles diluted in nutrient culture broth and distributed in ELISA plates. The copper cements (obtained from hydrometallurgical processes) and the commercial one were nanostructured employing a mechanical milling equipment. The results indicate that commercial copper nanoparticles (after 2.5 hours of milling) show growth inhibitory action of S. aureus strain. However, in the case of E. coli strains no inhibitory action has been observed. It was also determined that the minimal inhibitory concentration of the commercial copper is 20 μg/mL against S. aureus. On the other hand, copper cements (in solid and nanostructured form) do not show inhibitory effects.

A Novel Dopamine Sensor Based on Single-Walled Carbon Nanotubes/Nafion/Copper Nanoparticles Nanocomposites / 分析化学

An economic and facilely prepared dopamine ( DA) sensor have been successfully fabricated by the electrodeposition of copper on single-walled carbon nanotubes ( SWNTs )/Nafion-modified glassy carbon electrode. The morphology of the material was observed by scanning electron microscopy ( SEM) and element composition of the material was investigated by energy dispersive X-ray spectroscopy ( EDX ) . Tests with various scan rates and pH conditions indicated that an adsorption-controlled process occured in the electrochemical system. The mechanism of the electrode reaction of dopamine involved a two-electron process which was accompanied by a deprotonation step. Electrochemical parameters were calculated with the electron transfer number as 2 . 67 , the charge transfer coefficients as 0 . 6 , the apparent heterogeneous electron transfer rate constant as 1. 38 s-1 . Under the optimal conditions with differential pulse voltammetric measurement, the linear equation was Ipa(μA)=-0. 054c (μmol/L)-3. 82(R2=0. 9988), with linear range of 5-100 μmol/L and detection limit of 0 . 0135 μmol/L ( S/N=3 ) . The main advantages of sensor included facile fabrication approach, high sensitivity, good stability and high reproducibility. The sensor was applied to the detection of DA in volunteer urine by differential pulse voltammetry with favorable recoveries of 96 . 5%-100 . 4% and relative standard deviations (RSDs) of 1. 2%-2. 4%.