Research

Jump to: Review

23 pages, 6577 KiB

Open AccessArticle

Synthesis and Characterization of Citrate-Stabilized Gold-Coated Superparamagnetic Iron Oxide Nanoparticles for Biomedical Applications

by René Stein, Bernhard Friedrich, Marina Mühlberger, Nadine Cebulla, Eveline Schreiber, Rainer Tietze, Iwona Cicha, Christoph Alexiou, Silvio Dutz, Aldo R. Boccaccini and Harald Unterweger

Molecules 2020, 25(19), 4425; https://doi.org/10.3390/molecules25194425 - 26 Sep 2020

Cited by 16 | Viewed by 3748

Abstract

Surface-functionalized gold-coated superparamagnetic iron oxide nanoparticles (Au-SPIONs) may be a useful tool in various biomedical applications. To obtain Au-SPIONs, gold salt was precipitated onto citrate-stabilized SPIONs (Cit-SPIONs) using a simple, aqueous one-pot technique inspired by the Turkevich method of gold nanoparticle synthesis. By [...] Read more.

Surface-functionalized gold-coated superparamagnetic iron oxide nanoparticles (Au-SPIONs) may be a useful tool in various biomedical applications. To obtain Au-SPIONs, gold salt was precipitated onto citrate-stabilized SPIONs (Cit-SPIONs) using a simple, aqueous one-pot technique inspired by the Turkevich method of gold nanoparticle synthesis. By the further stabilization of the Au-SPION surface with additional citrate (Cit-Au-SPIONs), controllable and reproducible Z-averages enhanced long-term dispersion stability and moderate dispersion pH values were achieved. The citrate concentration of the reaction solution and the gold/iron ratio was found to have a major influence on the particle characteristics. While the gold-coating reduced the saturation magnetization to 40.7% in comparison to pure Cit-SPIONs, the superparamagnetic behavior of Cit-Au-SPIONs was maintained. The formation of nanosized gold on the SPION surface was confirmed by X-ray diffraction measurements. Cit-Au-SPION concentrations of up to 100 µg Fe/mL for 48 h had no cytotoxic effect on Jurkat cells. At a particle concentration of 100 µg Fe/mL, Jurkat cells were found to take up Cit-Au-SPIONs after 24 h of incubation. A significantly higher attachment of thiol-containing L-cysteine to the particle surface was observed for Cit-Au-SPIONs (53%) in comparison to pure Cit-SPIONs (7%). Full article

(This article belongs to the Special Issue Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications)

► Show Figures

Figure 1

15 pages, 3358 KiB

Open AccessArticle

MgONPs Can Boost Plant Growth: Evidence from Increased Seedling Growth, Morpho-Physiological Activities, and Mg Uptake in Tobacco (Nicotiana tabacum L.)

by Lin Cai, Minghong Liu, Zhongwei Liu, Huikuan Yang, Xianchao Sun, Juanni Chen, Shunyu Xiang and Wei Ding

Molecules 2018, 23(12), 3375; https://doi.org/10.3390/molecules23123375 - 19 Dec 2018

Cited by 53 | Viewed by 4489

Abstract

In this study, we documented the impact of magnesium oxide nanoparticles (MgONPs) on the various morpho-physiological changes by root irrigation in tobacco plants in the matrix media, as well as the uptake and accumulation of the NPs over a range of concentrations (50–250 [...] Read more.

In this study, we documented the impact of magnesium oxide nanoparticles (MgONPs) on the various morpho-physiological changes by root irrigation in tobacco plants in the matrix media, as well as the uptake and accumulation of the NPs over a range of concentrations (50–250 μg/mL). Our results showed that the seed germination rate was not affected following exposure to MgONPs for 5 days. Enhanced plant growth together with increased peroxidase activity (39.63 U mg⁻¹ protein in the 250 μg/mL MgONPs treatment, 36.63 U mg⁻¹ protein in the control), superoxide dismutase activity (30.15 U mg⁻¹ protein compared to 26.95 U mg⁻¹ protein in the control), and chlorophyll content (the chlorophyll a and b contents in 0 and 250 μg/mL of MgONPs were 0.21, 0.12 μg/g to 1.21, 0.67 μg/g, respectively) were observed after 30 days of MgONP treatment. However, the malondialdehyde, protein, and relative water contents did not differ significantly, indicating that the NPs in the test concentrations had no phytotoxicity and even promoted plant growth. Scanning electron microscopy and paraffin section observations indicated that the MgONPs did not affect the plant tissue structures and cells. In addition, an elevated Mg content was detected in the plant tissues exposed to MgONPs, suggesting that the Mg was taken up by the tobacco roots and translocated to the shoots and leaves, which were probably the most important tools to cause an increase in the chlorophyll content and stimulate growth. In particular, compared with the controls, a substantially higher Mg content was observed in the leaves (12.93 mg/g in the MgONPs treatment, 9.30 mg/g in the control) exposed to 250 μg/mL MgONPs, especially in the lower and middle leaves. This result confirmed that the contents of plant Mg-element in the old leaves were increased by MgONPs. In summary, this study investigated increased Mg uptake and growth stimulation, as well as the induction of various positive morpho-physiological changes to tobacco plants when exposed to MgONPs. Results elucidate the promotional impact of the NPs on plant health and their implications for agricultural safety and security. Full article

(This article belongs to the Special Issue Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications)

► Show Figures

Figure 1

15 pages, 2621 KiB

Open AccessArticle

Phyto-Mediated Photo Catalysed Green Synthesis of Silver Nanoparticles Using Durio Zibethinus Seed Extract: Antimicrobial and Cytotoxic Activity and Photocatalytic Applications

by Samuggam Sumitha, Sethu Vasanthi, Sivadasan Shalini, Suresh V. Chinni, Subash C.B. Gopinath, Periasamy Anbu, Mohammed Baidi Bahari, Rajak Harish, Sathasivam Kathiresan and Veerasamy Ravichandran

Molecules 2018, 23(12), 3311; https://doi.org/10.3390/molecules23123311 - 13 Dec 2018

Cited by 60 | Viewed by 5016

Abstract

In the present study, we have developed a green approach for the synthesis of silver nanoparticles (DSAgNPs) using aqueous extract of Durio zibethinus seed and determined its antibacterial, photocatalytic and cytotoxic effects. Surface plasmon resonance confirmed the formation of DSAgNPs with a maximum [...] Read more.

In the present study, we have developed a green approach for the synthesis of silver nanoparticles (DSAgNPs) using aqueous extract of Durio zibethinus seed and determined its antibacterial, photocatalytic and cytotoxic effects. Surface plasmon resonance confirmed the formation of DSAgNPs with a maximum absorbance (λ_max) of 420 nm. SEM and TEM images revealed DSAgNPs were spherical and rod shaped, with a size range of 20 nm and 75 nm. The zeta potential was found to be −15.41 mV. XRD and EDX analyses confirmed the nature and presence of Ag and AgCl. DSAgNPs showed considerable antibacterial activity, exhibited better cytotoxicity against brine shrimp, and shown better photocatalytic activity against methylene blue. Based on the present research work, it can be concluded that DSAgNPs could be used in the field of water treatment, pharmaceuticals, biomedicine, biosensor and nanotechnology in near future. Full article

(This article belongs to the Special Issue Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications)

► Show Figures

Graphical abstract

12 pages, 2614 KiB

Open AccessArticle

Antimicrobial Potential of Silver Nanoparticles Synthesized Using Medicinal Herb Coptidis rhizome

by Garima Sharma, Ju-Suk Nam, Ashish Ranjan Sharma and Sang-Soo Lee

Molecules 2018, 23(9), 2268; https://doi.org/10.3390/molecules23092268 - 05 Sep 2018

Cited by 58 | Viewed by 7059

Abstract

Coptidis rhizome contains several alkaloids that are bioactive agents of therapeutic value. We propose an eco-friendly method to synthesize biocompatible silver nanoparticles (AgNPs) using the aqueous extract of Coptidis rhizome. Silver ions were reduced to AgNPs using the aqueous extract of Coptidis [...] Read more.

Coptidis rhizome contains several alkaloids that are bioactive agents of therapeutic value. We propose an eco-friendly method to synthesize biocompatible silver nanoparticles (AgNPs) using the aqueous extract of Coptidis rhizome. Silver ions were reduced to AgNPs using the aqueous extract of Coptidis rhizome, indicating that Coptidis rhizome can be used for the biosynthesis of AgNPs. The time and the concentration required for conversion of silver ions into AgNPs was optimized using UV-absorbance spectroscopy and inductively coupled plasma spectroscopy (ICP). Biosynthesized AgNPs showed a distinct UV-Visible absorption peak at 420 nm. ICP analysis showed that the time required for the completion of biosynthesis was around 20 min. Microscopic images showed that nanoparticles synthesized were of spherical shape and the average diameter of biosynthesized AgNPs was less than 30 nm. XRD analysis also confirmed the size of AgNps and revealed their crystalline nature. The interaction of AgNPs with phytochemicals present in Coptidis rhizome extract was observed in FTIR analysis. The antimicrobial property of AgNPs was evaluated using turbidity measurements. Coptidis rhizome-mediated biosynthesized AgNPs showed significant anti-bacterial activities against Escherichia coli and Staphylococcus aureus that are commonly involved in various types of infections, indicating their potential as an effective anti-bacterial agent. Full article

(This article belongs to the Special Issue Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications)

► Show Figures

Figure 1

14 pages, 1857 KiB

Open AccessArticle

Histopathology of the Liver, Kidney, and Spleen of Mice Exposed to Gold Nanoparticles

by Khalid Elfaki Ibrahim, Mohsen Ghaleb Al-Mutary, Amel Omer Bakhiet and Haseeb Ahmad Khan

Molecules 2018, 23(8), 1848; https://doi.org/10.3390/molecules23081848 - 25 Jul 2018

Cited by 132 | Viewed by 14143

Abstract

Gold nanoparticles (GNPs) are biocompatible nanomaterials that are currently researched for biomedical applications such as imaging and targeted drug delivery. In this investigation, we studied the effects of a single dose (injected on day 1) as well as a priming dose (two injections [...] Read more.

Gold nanoparticles (GNPs) are biocompatible nanomaterials that are currently researched for biomedical applications such as imaging and targeted drug delivery. In this investigation, we studied the effects of a single dose (injected on day 1) as well as a priming dose (two injections with a gap of one week) of 5 nm, 20 nm, and 50 nm diameter GNPs on the structural and biochemical changes in the liver, kidney, and spleen of mice. The results showed that small sized GNPs (5 nm) produced significant pathological changes in the liver on day 2 that gradually reduced on day 8. The medium (20 nm) and large (50 nm) sized GNPs preferentially targeted the spleen and caused significant pathological changes to the spleen architecture on day 2 that persisted on day 8 as well. There were minimal and insignificant pathological changes to the kidneys irrespective of the GNPs size. The animals that were primed with the pre-exposure of GNPs did not show any aggravation of histological changes after the second dose of the same GNPs. None of the dose regimens of the GNPs were able to significantly affect the markers of oxidative stress including glutathione (GSH) and malondialdehyde (MDA) in all of the organs that were studied. In conclusion, the size of GNPs plays an important role in their pathological effects on different organs of mice. Moreover, the primed animals become refractory to further pathological changes after the second dose of GNPs, suggesting the importance of a priming dose in medical applications of GNPs. Full article

(This article belongs to the Special Issue Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications)

► Show Figures

Graphical abstract

14 pages, 5661 KiB

Open AccessArticle

Plate-Focusing Based on a Meta-Molecule of Dendritic Structure in the Visible Frequency

by Suna Cheng, Di An, Huan Chen and Xiaopeng Zhao

Molecules 2018, 23(6), 1323; https://doi.org/10.3390/molecules23061323 - 31 May 2018

Cited by 2 | Viewed by 2970

Abstract

To study the potential application of metasurfaces in lens technology, we propose a dendritic meta-molecule surface (also referred to as a dendritic metasurface) and realize the focusing effect in the visible spectrum through simulations and experiments. Using asymmetric dendritic structures, this metasurface can [...] Read more.

To study the potential application of metasurfaces in lens technology, we propose a dendritic meta-molecule surface (also referred to as a dendritic metasurface) and realize the focusing effect in the visible spectrum through simulations and experiments. Using asymmetric dendritic structures, this metasurface can achieve distinct broadband anomalous reflection and refraction. When the metasurface is rotated by 180° around the z axis, anomalous reflection and refraction in vertically incident optical waves are in opposite directions. Considering this feature, a metasurface is designed to achieve a prominent plate-focusing effect. Samples with a transmission peak of green light at 555 nm, yellow light at 580 nm, and red light at 650 nm were prepared using bottom-up electrochemical deposition, and the focus intensity of approximately 10% and focal length of almost 600 µm were experimentally demonstrated. Full article

(This article belongs to the Special Issue Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications)

► Show Figures

Figure 1

Review

Jump to: Research

28 pages, 8646 KiB

Open AccessFeature PaperReview

Synthetic Methodologies to Gold Nanoshells: An Overview

by Yu-Chen Wang, Éric Rhéaume, Frédéric Lesage and Ashok Kakkar

Molecules 2018, 23(11), 2851; https://doi.org/10.3390/molecules23112851 - 02 Nov 2018

Cited by 36 | Viewed by 8328

Abstract

Gold nanostructures that can be synthetically articulated to adapt diverse morphologies, offer a versatile platform and tunable properties for applications in a variety of areas, including biomedicine and diagnostics. Among several conformational architectures, gold nanoshells provide a highly advantageous combination of properties that [...] Read more.

Gold nanostructures that can be synthetically articulated to adapt diverse morphologies, offer a versatile platform and tunable properties for applications in a variety of areas, including biomedicine and diagnostics. Among several conformational architectures, gold nanoshells provide a highly advantageous combination of properties that can be fine-tuned in designing single or multi-purpose nanomaterials, especially for applications in biology. One of the important parameters for evaluating the efficacy of gold nano-architectures is their reproducible synthesis and surface functionalization with desired moieties. A variety of methods now exist that allow fabrication and chemical manipulation of their structure and resulting properties. This review article provides an overview and a discussion of synthetic methodologies to a diverse range of gold nanoshells, and a brief summary of surface functionalization and characterization methods employed to evaluate their overall composition. Full article

(This article belongs to the Special Issue Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications)

► Show Figures

Graphical abstract

23 pages, 733 KiB

Open AccessReview

Bactericidal Properties of Plants-Derived Metal and Metal Oxide Nanoparticles (NPs)

by Sin-Yeang Teow, Magdelyn Mei-Theng Wong, Hooi-Yeen Yap, Suat-Cheng Peh and Kamyar Shameli

Molecules 2018, 23(6), 1366; https://doi.org/10.3390/molecules23061366 - 06 Jun 2018

Cited by 36 | Viewed by 5767

Abstract

Nanoparticles (NPs) are nano-sized particles (generally 1–100 nm) that can be synthesized through various methods. The wide range of physicochemical characteristics of NPs permit them to have diverse biological functions. These particles are versatile and can be adopted into various applications, particularly in [...] Read more.

Nanoparticles (NPs) are nano-sized particles (generally 1–100 nm) that can be synthesized through various methods. The wide range of physicochemical characteristics of NPs permit them to have diverse biological functions. These particles are versatile and can be adopted into various applications, particularly in biomedical field. In the past five years, NPs’ roles in biomedical applications have drawn considerable attentions, and novel NPs with improved functions and reduced toxicity are continuously increasing. Extensive studies have been carried out in evaluating antibacterial potentials of NPs. The promising antibacterial effects exhibited by NPs highlight the potential of developing them into future generation of antimicrobial agents. There are various methods to synthesize NPs, and each of the method has significant implication on the biological action of NPs. Among all synthetic methods, green technology is the least toxic biological route, which is particularly suitable for biomedical applications. This mini-review provides current update on the antibacterial effects of NPs synthesized by green technology using plants. Underlying challenges in developing NPs into future antibacterials in clinics are also discussed at the present review. Full article

(This article belongs to the Special Issue Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Metallic Nanoparticles: From Synthesis, Structure-Property Relationships to Applications

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (8 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI