Research

Jump to: Review

12 pages, 2846 KiB

Open AccessArticle

Interleukin 6 Plays a Role in the Migration of Magnetically Levitated Mesenchymal Stem Cells Spheroids

by Jake Casson, Sam O’Kane, Carol-Anne Smith, Matthew John Dalby and Catherine Cecilia Berry

Appl. Sci. 2018, 8(3), 412; https://doi.org/10.3390/app8030412 - 11 Mar 2018

Cited by 11 | Viewed by 5893

Mesenchymal stem cells (MSCs) reside quiescently within a specialised ‘niche’ environment in the bone marrow. However, following appropriate signalling cues, MSCs mobilise and migrate out from the niche, typically toward either sites of injury (a regenerative response) or toward primary tumours (an intrinsic [...] Read more.

Mesenchymal stem cells (MSCs) reside quiescently within a specialised ‘niche’ environment in the bone marrow. However, following appropriate signalling cues, MSCs mobilise and migrate out from the niche, typically toward either sites of injury (a regenerative response) or toward primary tumours (an intrinsic homing response, which promotes MSCs as cellular vectors for therapeutic delivery). To date, very little is known about MSC mobilisation. By adopting a 3D MSC niche model, whereby MSC spheroids are cultured within a type I collagen gel, recent studies have highlighted interleukin-6 (IL-6) as a key cytokine involved in MSC migration. Herein, the ability of IL-6 to induce MSC migration was further investigated, and the key matrix metalloproteinases used to effect cell mobilisation were identified. Briefly, the impact of IL-6 on the MSC migration in a two-dimensional model systems was characterised—both visually using an Ibidi chemotaxis plate array (assessing for directional migration) and then via a standard 2D monolayer experiment, where cultured cells were challenged with IL-6 and extracted media tested using an Abcam Human MMP membrane antibody array. The 2D assay displayed a strong migratory response toward IL-6 and analysis of the membrane arrays data showed significant increases of several key MMPs. Both data sets indicated that IL-6 is important in MSC mobilisation and migration. We also investigated the impact of IL-6 induction on MSCs in 3D spheroid culture, serving as a simplistic model of the bone marrow niche, characterised by fluorescently tagged magnetic nanoparticles and identical membrane antibody arrays. An increase in MMP levels secreted by cells treated with 1 ng/mL IL-6 versus control conditions was noted in addition to migration of cells away from the central spheroid mass. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Figure 1

13 pages, 3350 KiB

Open AccessArticle

Analysis of Xanthine Oxidase Inhibitors from Clerodendranthus spicatus with Xanthine Oxidase Immobilized Silica Coated Fe₃O₄ Nanoparticles

by Liangliang Liu, Mengmeng Yuan, Siqi Huang, Jianjun Li, Defang Li and Lining Zhao

Appl. Sci. 2018, 8(2), 158; https://doi.org/10.3390/app8020158 - 24 Jan 2018

Cited by 11 | Viewed by 4309

Abstract

In this study, xanthine oxidase immobilized silica coated Fe₃O₄ nanoparticles (Fe₃O₄@SiO₂-XO) were successfully prepared and characterized by transmission electron microscope, X-ray powder diffraction, Fourier transform infrared spectroscopy and vibrating sample magnetometer. The average diameter [...] Read more.

In this study, xanthine oxidase immobilized silica coated Fe₃O₄ nanoparticles (Fe₃O₄@SiO₂-XO) were successfully prepared and characterized by transmission electron microscope, X-ray powder diffraction, Fourier transform infrared spectroscopy and vibrating sample magnetometer. The average diameter of the Fe₃O₄ nanoparticles was about 300 nm to 350 nm with a shell thickness of 60 nm. The maximum saturation magnetization of the Fe₃O₄@SiO₂-XO nanoparticles was 44.9 emu/g, which ensured the separation from the medium within one minute by using an ordinary magnet. A xanthine oxidase (XO) inhibitor screening method using Fe₃O₄@SiO₂-XO nanoparticles was established and utilized in the extract of Clerodendranthus spicatus. Under the optimized conditions, two compounds were screened out and identified as gardenin B and eupatorin. The half maximal inhibitory concentration (IC₅₀) values of these two compounds were 1.488 μg/mL and 11.197 μg/mL, respectively. The interactions between these two compounds and XO were investigated by the fluorescence spectroscopic method. The results suggested that the quenching effects of gardenin B and eupatorin were due to a static quenching mechanism. Furthermore, gardenin B showed stronger binding capacity than that of eupatorin. In conclusion, this screening method exhibited efficiency and reusability in screening, identification and analysis of enzyme inhibitors from complex mixtures. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Figure 1

16 pages, 5347 KiB

Open AccessArticle

Combined Effects of Fe₃O₄ Nanoparticles and Chemotherapeutic Agents on Prostate Cancer Cells In Vitro

by Kanako Kojima, Sanai Takahashi, Shungo Saito, Yoshihiro Endo, Tadashi Nittami, Tadashige Nozaki, Ranbir Chander Sobti and Masatoshi Watanabe

Appl. Sci. 2018, 8(1), 134; https://doi.org/10.3390/app8010134 - 18 Jan 2018

Cited by 15 | Viewed by 5739

Abstract

Patients with metastatic castration-resistant prostate cancer (mCRPC) have poor outcomes. Docetaxel (DTX)-based therapy is a current standard treatment for patients with mCRPC. Approaches combining conventional chemotherapeutic agents and nanoparticles (NPs), particularly iron oxide NPs, may overcome the serious side effects and drug resistance, [...] Read more.

Patients with metastatic castration-resistant prostate cancer (mCRPC) have poor outcomes. Docetaxel (DTX)-based therapy is a current standard treatment for patients with mCRPC. Approaches combining conventional chemotherapeutic agents and nanoparticles (NPs), particularly iron oxide NPs, may overcome the serious side effects and drug resistance, resulting in the establishment of new therapeutic strategies. We previously reported the combined effects of Fe₃O₄ nanoparticles (Fe₃O₄ NPs) with DTX on prostate cancer cells in vitro. In this study, we investigated the combined effects of Fe₃O₄ NPs and rapamycin or carboplatin on prostate cancer cells in vitro. Treatment of DU145 and PC-3 cells with Fe₃O₄ NPs increased intracellular reactive oxygen species (ROS) levels in a concentration-dependent manner. Treatment of both cell lines with 100 μg/mL Fe₃O₄ NPs for 72 h resulted in significant inhibition of cell viability with a different inhibitory effect. Combination treatments with 100 µg/mL Fe₃O₄ NPs and 10 µM carboplatin or 10 nM rapamycin in DU145 and PC-3 cells significantly decreased cell viability. Synergistic effects on apoptosis were observed in PC-3 cells treated with Fe₃O₄ NPs and rapamycin and in DU145 cells with Fe₃O₄ NPs and carboplatin. These results suggest the possibility of combination therapy with Fe₃O₄ NPs and various chemotherapeutic agents as a novel therapeutic strategy for patients with mCRPC. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Figure 1

11 pages, 2945 KiB

Open AccessArticle

Reduction of T2 Relaxation Rates due to Large Volume Fractions of Magnetic Nanoparticles for All Motional Regimes

by Bashar Issa

Appl. Sci. 2018, 8(1), 101; https://doi.org/10.3390/app8010101 - 11 Jan 2018

Cited by 2 | Viewed by 3434

Abstract

The effect of high volume fraction of magnetic nanoparticles (MNP) on Magnetic Resonance Imaging (MRI) transverse relaxation rates (R₂ = 1/T₂ and R₂* = 1/T₂*) is investigated using Monte Carlo (MC) simulations. Theoretical models [...] Read more.

The effect of high volume fraction of magnetic nanoparticles (MNP) on Magnetic Resonance Imaging (MRI) transverse relaxation rates (R₂ = 1/T₂ and R₂* = 1/T₂*) is investigated using Monte Carlo (MC) simulations. Theoretical models assume that particles occupy a small volume fraction of the sample space. Results presented in this work show that models based on both motional averaged (MAR) and static dephasing (SDR) regimes respectively underestimate and overestimate relaxation rates at large volume fractions. Furthermore, both R₂* and R₂* become echo-time dependent. This suggests that diffusion is involved with larger echo-times producing smaller relaxation rates due to better averaging of the magnetic field gradients. Findings emphasize the need for the models to be modified to take account of high particle concentration especially important for application involving clustering and trapping of nanoparticles inside cells. This is important in order to improve the design process of MNP Contrast Agents. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Graphical abstract

3290 KiB

Open AccessArticle

Investigating the Role of Shell Thickness and Field Cooling on Saturation Magnetization and Its Temperature Dependence in Fe₃O₄/γ-Fe₂O₃ Core/Shell Nanoparticles

by Ihab M. Obaidat, Chiranjib Nayek and Kaustuv Manna

Appl. Sci. 2017, 7(12), 1269; https://doi.org/10.3390/app7121269 - 05 Dec 2017

Cited by 24 | Viewed by 5808

Abstract

Understanding saturation magnetization and its behavior with particle size and temperature are essential for medical applications such magnetic hyperthermia. We report the effect of shell thickness and field cooling on the saturation magnetization and its behavior with temperature in Fe₃O₄ [...] Read more.

Understanding saturation magnetization and its behavior with particle size and temperature are essential for medical applications such magnetic hyperthermia. We report the effect of shell thickness and field cooling on the saturation magnetization and its behavior with temperature in Fe₃O₄/γ-Fe₂O₃ core/shell nanoparticles of fixed core diameter (8 nm) and several shell thicknesses. X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM, high-resolution transmission electron microscopy (HRTEM)) were used to investigate the phase and the morphology of the samples. Selected area electron diffraction (SAED) confirmed the core/shell structure and phases. Using a SQUID (San Diego, CA, USA), magnetic measurements were conducted in the temperature range of 2 to 300 K both under zero field-cooling (ZFC) and field-cooling (FC) protocols at several field-cooling values. In the ZFC state, considerable enhancement of saturation magnetization was obtained with the increase of shell thickness. After field cooling, we observed a drastic enhancement of the saturation magnetization in one sample up to 120 emu/g (50% larger than the bulk value). In both the FC and ZFC states, considerable deviations from the original Bloch’s law were observed. These results are discussed and attributed to the existence of interface spin-glass clusters which are modified by the changes in the shell thickness and the field-cooling. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Graphical abstract

5175 KiB

Open AccessFeature PaperArticle

Targeted Molecular Imaging of Pancreatic Cancer with a Miniature Endoscope

by Xianjin Dai, Weiping Qian, Hao Yang, Lily Yang and Huabei Jiang

Appl. Sci. 2017, 7(12), 1241; https://doi.org/10.3390/app7121241 - 30 Nov 2017

Cited by 2 | Viewed by 4249

Abstract

It is highly desirable to develop novel approaches to improve patient survival rate of pancreatic cancer through early detection. Here, we present such an approach based on photoacoustic and fluorescence molecular imaging of pancreatic tumor using a miniature multimodal endoscope in combination with [...] Read more.

It is highly desirable to develop novel approaches to improve patient survival rate of pancreatic cancer through early detection. Here, we present such an approach based on photoacoustic and fluorescence molecular imaging of pancreatic tumor using a miniature multimodal endoscope in combination with targeted multifunctional iron oxide nanoparticles (IONPs). A novel fan-shaped scanning mechanism was developed to minimize the invasiveness for endoscopic imaging of pancreatic tumors. The results show that the enhancements in photoacoustic and fluorescence signals using amino-terminal fragment (ATF) targeted IONPs were ~four to six times higher compared to that using non-targeted IONPs. Our study indicates the potential of the combination of the multimodal photoacoustic-fluorescence endoscopy and targeted multifunctional nanoparticles as an efficient tool to provide improved specificity and sensitivity for pancreatic cancer detection. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Figure 1

4367 KiB

Open AccessArticle

A Fast and Cost-Effective Detection of Melamine by Surface Enhanced Raman Spectroscopy Using a Novel Hydrogen Bonding-Assisted Supramolecular Matrix and Gold-Coated Magnetic Nanoparticles

by Jing Neng, Jiayuan Tan, Kan Jia and Peilong Sun

Appl. Sci. 2017, 7(5), 475; https://doi.org/10.3390/app7050475 - 03 May 2017

Cited by 16 | Viewed by 6879

Abstract

A fast and cost-effective melamine detection approach has been developed based on surface enhanced Raman spectroscopy (SERS) using a novel hydrogen bonding-assisted supramolecular matrix. The detection utilizes Fe₃O₄/Au magnetic nanoparticles coated with 5-aminoorotic acid (AOA) as a SERS active [...] Read more.

A fast and cost-effective melamine detection approach has been developed based on surface enhanced Raman spectroscopy (SERS) using a novel hydrogen bonding-assisted supramolecular matrix. The detection utilizes Fe₃O₄/Au magnetic nanoparticles coated with 5-aminoorotic acid (AOA) as a SERS active substrate (Fe₃O₄/Au–AOA), and Rhodamine B (RhB) conjugated AOA as a Raman reporter (AOA–RhB). Upon mixing the reagents with melamine, a supramolecular complex [Fe₃O₄/Au–AOA•••melamine•••AOA–RhB] was formed due to the strong multiple hydrogen bonding interactions between AOA and melamine. The complex was separated and concentrated to a pellet by an external magnet and used as a supramolecular matrix for the melamine detection. Laser excitation of the complex pellet produced a strong SERS signal diagnostic for RhB. The logarithmic intensity of the characteristic RhB peaks was found to be proportional to the concentration of melamine with a limit of detection of 2.5 µg/mL and a detection linearity range of 2.5~15.0 µg/mL in milk. As Fe₃O₄ nanoparticles and AOA are thousands of times less expensive than the monoclonal antibody used in a traditional sandwich immunoassay, the current assay drastically cut down the cost of melamine detection. The current approach affords promise as a biosensor platform that cuts down sample pre-treatment steps and measurement expense. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Figure 1

Review

Jump to: Research

32 pages, 3614 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Bimetallic Nanoparticles: Enhanced Magnetic and Optical Properties for Emerging Biological Applications

by Pannaree Srinoi, Yi-Ting Chen, Varadee Vittur, Maria D. Marquez and T. Randall Lee

Appl. Sci. 2018, 8(7), 1106; https://doi.org/10.3390/app8071106 - 09 Jul 2018

Cited by 187 | Viewed by 13038

Abstract

Metal nanoparticles are extensively studied due to their unique chemical and physical properties, which differ from the properties of their respective bulk materials. Likewise, the properties of heterogeneous bimetallic structures are far more attractive than those of single-component nanoparticles. For example, the incorporation [...] Read more.

Metal nanoparticles are extensively studied due to their unique chemical and physical properties, which differ from the properties of their respective bulk materials. Likewise, the properties of heterogeneous bimetallic structures are far more attractive than those of single-component nanoparticles. For example, the incorporation of a second metal into a nanoparticle structure influences and can potentially enhance the optical/plasmonic and magnetic properties of the material. This review focuses on the enhanced optical/plasmonic and magnetic properties offered by bimetallic nanoparticles and their corresponding impact on biological applications. In this review, we summarize the predominant structures of bimetallic nanoparticles, outline their synthesis methods, and highlight their use in biological applications, both diagnostic and therapeutic, which are dictated by their various optical/plasmonic and magnetic properties. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Graphical abstract

23 pages, 5502 KiB

Open AccessFeature PaperReview

Recent Progress in Synthesis and Functionalization of Multimodal Fluorescent-Magnetic Nanoparticles for Biological Applications

by Raquel Serrano García, Shelley Stafford and Yurii K. Gun’ko

Appl. Sci. 2018, 8(2), 172; https://doi.org/10.3390/app8020172 - 25 Jan 2018

Cited by 56 | Viewed by 8758

Abstract

There is a great interest in the development of new nanomaterials for multimodal imaging applications in biology and medicine. Multimodal fluorescent-magnetic based nanomaterials deserve particular attention as they can be used as diagnostic and drug delivery tools, which could facilitate the diagnosis and [...] Read more.

There is a great interest in the development of new nanomaterials for multimodal imaging applications in biology and medicine. Multimodal fluorescent-magnetic based nanomaterials deserve particular attention as they can be used as diagnostic and drug delivery tools, which could facilitate the diagnosis and treatment of cancer and many other diseases. This review focuses on the recent developments of magnetic-fluorescent nanocomposites and their biomedical applications. The recent advances in synthetic strategies and approaches for the preparation of fluorescent-magnetic nanocomposites are presented. The main biomedical uses of multimodal fluorescent-magnetic nanomaterials, including biological imaging, cancer therapy and drug delivery, are discussed, and prospects of this field are outlined. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures

Figure 1

16 pages, 4593 KiB

Open AccessReview

Multimodal Magnetic-Plasmonic Nanoparticles for Biomedical Applications

by Shelley Stafford, Raquel Serrano Garcia and Yurii K. Gun’ko

Appl. Sci. 2018, 8(1), 97; https://doi.org/10.3390/app8010097 - 11 Jan 2018

Cited by 51 | Viewed by 7635

Abstract

Magnetic plasmonic nanomaterials are of great interest in the field of biomedicine due to their vast number of potential applications, for example, in molecular imaging, photothermal therapy, magnetic hyperthermia and as drug delivery vehicles. The multimodal nature of these nanoparticles means that they [...] Read more.

Magnetic plasmonic nanomaterials are of great interest in the field of biomedicine due to their vast number of potential applications, for example, in molecular imaging, photothermal therapy, magnetic hyperthermia and as drug delivery vehicles. The multimodal nature of these nanoparticles means that they are potentially ideal theranostic agents—i.e., they can be used both as therapeutic and diagnostic tools. This review details progress in the field of magnetic-plasmonic nanomaterials over the past ten years, focusing on significant developments that have been made and outlining the future work that still needs to be done in this fast emerging area. The review describes the main synthetic approaches to each type of magnetic plasmonic nanomaterial and the potential biomedical applications of these hybrid nanomaterials. Full article

(This article belongs to the Special Issue Biological Applications of Magnetic Nanoparticles)

► Show Figures