Pulmonary toxicity of Fe2O3, ZnFe2O4, NiFe2O4 and NiZnFe4O8 nanomaterials: Inflammation and DNA strand breaks

Exposure to metal oxide nanomaterials potentially occurs at the workplace. We investigated the toxicity of two Fe-oxides: Fe₂O₃ nanoparticles and nanorods; and three MFe₂O₄ spinels: NiZnFe₄O₈, ZnFe₂O₄, and NiFe₂O₄ nanoparticles. Mice were dosed 14, 43 or 128 μg by intratracheal instillation. Recovery periods were 1, 3, or 28 days. Inflammation – neutrophil influx into bronchoalveolar lavage (BAL) fluid – occurred for Fe₂O₃ rods (1 day), ZnFe₂O₄ (1, 3 days), NiFe₂O₄ (1, 3, 28 days), Fe₂O₃ (28 days) and NiZnFe₄O₈ (28 days). Conversion of mass-dose into specific surface-area-dose showed that inflammation correlated with deposited surface area and consequently, all these nanomaterials belong to the so-called low-solubility, low-toxicity class. Increased levels of DNA strand breaks were observed for both Fe₂O₃ particles and rods, in BAL cells three days post-exposure. To our knowledge, this is, besides magnetite (Fe₃O₄), the first study of the pulmonary toxicity of MFe₂O₄ spinel nanomaterials.     

Preparation,Characterization of 2-Deoxy-D-Glucose Functionalized Dimercaptosuccinic Acid-Coated Maghemite Nanoparticles for Targeting Tumor Cells

Purpose  

To report a modified preparation and to systematically study the structure, magnetic and other properties of γ-Fe₂O₃-DMSA-DG NPs (2-deoxy-D-glucose (2-DG) conjugated meso-2,3-dimercaptosuccinic acid coated γ-Fe₂O₃ nanoparticles) and test its ability to improve Hela tumor cells targeting in vitro compared to the γ-Fe₂O₃-DMSA NPs.     

A theranostic nanocomposite system based on iron oxide-drug nanocages for targeted magnetic field responsive chemotherapy

In this work, a theranostic nanocage system was developed for the targeted delivery of the anti-cancer agents camptothecin (CPT) and luotonin A (LuA). The core of the nanocage system (Fe₃O₄@OA-AD-SP NCs) was formed by biogenically synthesized Fe₃O₄ nanoparticles (NPs) decorated with a model anti-cancer drug (AD) and biosurfactant saponin (SP). The Fe₃O₄@OA-AD-SP NCs showed a high lipophilic AD loading efficiency (>80%) and a controlled pH-responsive drug release in stimulated cancerous cells in pH 6.4 media buffer. In addition, Fe₃O₄@OA-AD-SP NCs exhibited better serum protein binding efficacy at physiological pH values (7.4), furthering the important role of SP surface decoration. Particularly, these NCs showed better chemotherapeutic efficacy when examined in MCF-7 and HeLa cancer cell lines with a specific targeting capacity. Therefore, this study provides a new nano platform based on magnetic targeting and pH responsive lipophilic anticancer drug delivery to the cancer site.     

Toxicity evaluation of monodisperse PEGylated magnetic nanoparticles for nanomedicine

Abstract

Innovative nanotechnology aims to develop particles that are small, monodisperse, smart, and do not cause unintentional side effects. Uniform magnetic Fe₃O₄ nanoparticles (12?nm in size) were prepared by thermal decomposition of iron(III) oleate. To make them colloidally stable and dispersible in water and cell culture medium, they were modified with phosphonic acid- (PA) and hydroxamic acid (HA)-terminated poly(ethylene glycol) yielding PA-PEG@Fe₃O₄ and HA-PEG@Fe₃O₄ nanoparticles; conventional γ-Fe₂O₃ particles were prepared as a control. Advanced techniques were used to evaluate the properties and safety of the particles. Completeness of the nanoparticle coating was tested by real-time polymerase chain reaction. Interaction of the particles with primary human peripheral blood cells, cellular uptake, cytotoxicity, and immunotoxicity were also investigated. Amount of internalized iron in peripheral blood mononuclear cells was 72, 38, and 25?pg Fe/cell for HA-PEG@Fe₃O₄, γ-Fe₂O₃, and PA-PEG@Fe₃O₄, respectively. Nanoparticles were localized within the cytoplasm and in the extracellular space. No cytotoxic effect of both PEGylated nanoparticles was observed (0.12–75?μg/cm²) after 24 and 72-h incubation. Moreover, no suppressive effect was found on the proliferative activity of T-lymphocytes and T-dependent B-cell response, phagocytic activity of monocytes and granulocytes, and respiratory burst of phagocytes. Similarly, no cytotoxic effect of γ-Fe₂O₃ particles was observed. However, they suppressed the proliferative activity of T-lymphocytes (75?μg/cm², 72?h) and also decreased the phagocytic activity of monocytes (15?μg/cm², 24?h; 3–75?μg/cm², 72?h). We thus show that newly developed particles have great potential especially in cancer diagnostics and therapy.     

A Magnetic T7 Peptide&AS1411 Aptamer-Modified Microemulsion for Triple Glioma-Targeted Delivery of Shikonin and Docetaxel

Glioma-targeted drug delivery is a hugely challenging task because of the multibarrier in the brain. In this study, we report a magnetic T7 peptide&AS1411 aptamer-modified microemulsion for triple glioma-targeted delivery of shikonin and docetaxel (Fe₃O₄@T7/AS1411/DTX&SKN-M). Such a system comprises two tumor-targeted ligands (T7 peptide and AS1411 aptamer), ultra-small superparamagnetic iron oxide nanoparticle (Fe₃O₄), and shikonin&docetaxel-coloaded microemulsion (SKN&DTX-M). Fe₃O₄@T7/AS1411/DTX&SKN-M is capable of stably circulating in the blood, accumulating around the brain under an external magnetic field, distributing inside the glioma via the affinity to nucleolin/transferrin receptor, and retarding the growth of orthotopic glioma. Fe₃O₄@T7/AS1411/DTX&SKN-M encapsulated Fe₃O₄ nanoparticles in the core to obtain the superparamagnetism, which did not influence the main surface properties. Introducing 6% (wt%) of DSPE-PEG₂₀₀₀-T7 and 180 nM of AS1411 collaboratively enhanced the murine glioma (G422) cellular uptake of Fe₃O₄@T7/AS1411/DTX&SKN-M and thereby achieved the strongest antiproliferation among all the groups. Notably, the drug distribution at the brain sites of orthotopic Luc-G422 glioma tumor-bearing nude mice treated with Fe₃O₄@T7/AS1411/DTX&SKN-M was overwhelming among all the treatments. Most importantly, Fe₃O₄@T7/AS1411/DTX&SKN-M not only significantly reduced the luminescence signal at the brain areas of orthotopic Luc-G422 glioma mice but also prolonged the overall survival period. The enhancement of anti-glioma efficacy was associated with down-regulating the population of CD133- and CD44-positive cells within the tumors. In summary, such a triple glioma-targeted delivery of shikonin and docetaxel using combinational magnetism and T7/AS1411 modification strategies provides a promising method for synergistic and precise glioma therapy.     

PEGylated FePt@Fe2O3 core-shell magnetic nanoparticles: Potential theranostic applications and in vivo toxicity studies

Herein, we develop FePt@Fe₂O₃ core-shell magnetic nanoparticles as a T₂ magnetic resonance (MR) imaging contrast agent as well as a drug carrier for potential cancer theranostic applications. The FePt@Fe₂O₃ core-shell nanoparticles are synthesized and then functionalized with polyethylene glycol (PEG). Folic acid (FA) is conjugated on the surface of FePt@Fe₂O₃-PEG nanoparticles for effective targeting of folate receptor (FR)-positive tumor cells. A chemotherapy drug, doxorubicin (DOX), is then loaded onto those nanoparticles via hydrophobic physical adsorption, for targeted intracellular drug delivery and selective cancer cell killing. We then use those FePt@Fe₂O₃-PEG nanoparticles for in vivo MR imaging, observing obvious tumor MR contrasts, which resulted from both passive tumor accumulation and active tumor targeting of nanoparticles. Moreover, both in vitro and in vivo studies uncover no obvious toxicity for FePt@Fe₂O₃-PEG nanoparticles. Therefore, our PEGylated FePt@Fe₂O₃ core-shell nanoparticles could serve as a promising multifunctional theranostic nano-platform in imaging guided cancer therapy.From the Clinical EditorIn this study of PEGylated FePt@Fe₂O₃ core-shell magnetic nanoparticles, both therapeutic and diagnostic applications are demonstrated. Folic acid surface-conjugation resulted in uptake by folate receptor positive cancer cells, the iron oxide particles enabled MRI imaging using T2* weighted sequences, and the absorbed doxorubicin provided treatment effects in this model. Similar multi-modality approaches will hopefully find their way to clinical applications in the near future.     

Metabolomics reveals the role of acetyl-l-carnitine metabolism in γ-Fe2O3 NP-induced embryonic development toxicity via mitochondria damage

Iron oxides nanoparticles (FeO_X NPs), including α-Fe₂O₃, γ-Fe₂O₃, and Fe₃O₄, are employed in many technological applications. However, very few studies have investigated the embryonic developmental toxicity of FeO_X NPs. In this study, metabolomics analysis were used to uncover the potential mechanisms of FeO_X NPs developmental toxicity on embryo–larval zebrafish and mice. Our results indicated that γ-Fe₂O₃ NP treatment could cause increased mortality, dropped hatching rate, etc., while α-Fe₂O₃ and Fe₃O₄ NPs showed no obvious effect. Through metabolomics analysis, a total of 42 metabolites were found to be significantly changed between the γ-Fe₂O₃ NP-treated group and the control group (p?2O₃ NP treatment caused abnormal mitochondrion structure and a decrease in mitochondrial membrane potential in zebrafish embryos. Meanwhile, ATP synthesis was decreased while oxidative stress levels were affected. It is noteworthy that acetyl-l-carnitine (ALCAR) (p?=?6.79E???04) and l-carnitine (p?=?1.43E???03) were identified with minimal p values, the relationship between the two counter-balance was regulated by acetyltransferase (crata). Subsequently, we performed rescue experiments with ALCAR on zebrafish embryos, and found that the mortality rates reduced and hatching rates raised significantly in the γ-Fe₂O₃ NP-treated group. Additionally, γ-Fe₂O₃ exposure could lead to increased absorbed fetus rate, decreased placental weight, lower expression of acetyltransferase (Crat), reduced ATP synthesis as well as increased oxidative stress (p?2O₃ NP might affect the mitochondrial membrane potential and ATP synthesis by affecting the metabolism of ALCAR, thereby stimulating oxidative stress, cell apoptosis, and causing embryonic development toxicity.     

Synthesis of Schiff's base magnetic crosslinked chitosan-glyoxal/ZnO/Fe3O4 nanoparticles for enhanced adsorption of organic dye: Modeling and mechanism study

In this work, Schiff's base magnetic crosslinked chitosan-glyoxal/Fe₃O₄ composite (CS-G/Fe₃O₄) was synthesized and further developed by loading zinc oxide (ZnO) nanoparticles into its polymeric matrix. The final composite material of magnetic crosslinked chitosan-glyoxal/ZnO/Fe₃O₄ nanoparticles (CS-G/ZnO/Fe₃O₄ NPs) was tested for the removal of organic dye pollutant (reactive blue 19, RB19). The synthesized magnetic nanomaterials were characterized by several techniques such as CHN elemental analysis, Brunauer-Emmett-Teller analysis, vibrating-sample magnetometer, X–ray powder diffractometry, Fourier Transforms infrared, scanning electron microscope, energy dispersive X-Ray analysis, pH_pzc, and pH-potentiometric titrations. A statistical approach namely Box–Behnken design (BBD) was applied to optimize the synthesis conditions as well as adsorption key parameters (A: ZnO nanoparticles loading (0–50%), B: adsorbent dosage (0.02–0.1 g), C: pH (4–10), D: temperature (30–60 °C), and time E: (10–60 min)). The adsorption kinetic and equilibrium results were well described with pseudo-second order model and Freundlich isotherm model, respectively. The maximum adsorption capacity of CS-G/ZnO/Fe₃O₄ NPs for RB19 was 363.3 mg/g at 60 °C. The adsorption mechanism of RB19 onto CS-G/ZnO/Fe₃O₄ NPs can be ascribed to several types of interactions (e.g. electrostatic attractions, hydrogen bonding, and n-π interactions). This study provides a new and effective adsorbent for water remediation due to its recoverability and high efficiency in removing the organic dye pollutants.     

Berberine‐loaded Janus nanocarriers for magnetic field‐enhanced therapy against hepatocellular carcinoma

Berberine, an bioactive isoquinolin alkaloid from traditional Chinese herbs, is considered to be a promising agent based on its remarkable activity against hepatocellular carcinoma. However, the clinical application of this nature compound had been hampered owing to its properties such as poor aqueous solubility, low gastrointestinal absorption, and reduced bioavailability. Therefore, we developed Janus magnetic mesoporous silica nanoparticles (Fe₃O₄‐mSiO₂ NPs) consisting of a Fe₃O₄ head for magnetic targeting and a mesoporous SiO₂ body for berberine delivery. A pH‐sensitive group was introduced on the surface of mesoporous silica for berberine loading to develop a tumor microenvironment‐responsive nanocarrier, which exhibited uniform morphology, good superparamagnetic properties, high drug‐loading amounts, superior endocytic ability, and low cytotoxicity. Berberine‐loaded Fe₃O₄‐mSiO₂ NPs exerted extraordinarily high specificity for hepatocellular carcinoma cells, which was due to the pH‐responsive berberine release, as well as higher endocytosis capacity in hepatocellular carcinoma cells rather than normal liver cells. More importantly, an external magnetic field could significantly improve antitumor activity of Ber‐loaded Fe₃O₄‐mSiO₂ NPs through enhancing berberine internalization. Taken together, our results suggest that Janus nanocarriers driven by the magnetic field may provide an effective and safe way to facilitate clinical use of berberine against hepatocellular carcinoma.     

Nanoecotoxicology study of the response of magnetic O-Carboxymethylchitosan loaded silver nanoparticles on Artemia salina

Magnetic silver nanoparticles (MNPAg) are interesting nanotechnology materials with borderless environmental science, that can be used to disinfect water contaminated with pathogenic bacteria. The use of MNPAg leads to increased risk of nanomaterial contamination in the environment, especially natural water sources, with harmful effects on the ecosystem. This study investigating survival and enzyme activity of magnetic O-carboxymethylchitosan loaded silver nanoparticle on Artemia salina. The results showed that mortality increased with increasing concentrations of MNPAg. O-Carboxymethylchitosan loaded silver nanoparticles were found to be more toxic, with a LC₅₀ of 902.1 mg/L for γ-Fe₂O₃/Ag without reducing agent. Accumulation of silver on Artemia salina depends on the type of nanoparticle. Accumulation of nanoparticle containing polymers (carboxymethylchitosan/γ-Fe₂O₃/Ag without reducing agent, carboxymethylchitosan/γ-Fe₂O₃/Ag reduced with sucrose and carboxymethylchitosan/γ-Fe₂O₃/Ag reduced with NaBH₄) were found to be higher than γ-Fe₂O₃/Ag reduced with NaBH₄, γ-Fe₂O₃/Ag reduced with sucrose and γ-Fe₂O₃/Ag without reducing agent under the same experimental conditions. The antioxidant enzyme (CAT, SOD and GST) activities increased slightly following exposure, indicating that the toxic effects are related to oxidative stress. The combined results so far indicate that MNPA does not have the potential to affect aquatic organisms when released into the ecosystem.     

Synthesis,purification, and anticancer effect of magnetic Fe3O4-loaded poly (lactic-co-glycolic) nanoparticles of the natural drug tetrandrine

Abstract

Here, we have successfully synthesised and purified multifunctional PLGA-based nanoparticles by the co-encapsulation of an anticancer drug (tetrandrine) and a magnetic material (Fe₃O₄). The obtained Tet-Fe₃O₄-PLGA NPs had a uniform spherical shape with a particle size of approximately 199?nm and a negative surface charge of –18.0?mV, displaying a high encapsulation efficiency. Furthermore, TEM studies provided representative images of the purification process of the magnetic nanoparticles with MACS^® technology. The MFM and VSM results indicated that both the Fe₃O₄ NPs and Tet-Fe₃O₄-PLGA NPs were superparamagnetic. The DSC spectrum demonstrated that Tet was successfully encapsulated within the PLGA-based nanoparticles. Significantly, the release studies revealed NPs had a relatively slower release rate than free Tet after 8?h’s initial burst release, which had decreased from 98% to 65% after 24?h. In vitro cellular studies revealed that NPs could effectively penetrate into A549 cells and A549 multicellular spheroids to exert cytotoxicity, displaying a significantly high anti-proliferation effect. Moreover, western blot demonstrated that the co-loaded NPs had a higher anticancer activity by injuring lysosomes to activate the mitochondria pathway and induce A549 cell apoptosis. The magnetic characteristics and high anticancer activity support the use of Tet/Fe₃O₄ co-loaded PLGA-based nanoparticles as a promising strategy in the treatment of lung cancer.     

Multifunctional nanoparticles of Fe3O4@SiO2(FITC)/PAH conjugated the recombinant plasmid of pIRSE2-EGFP/VEGF165 with dual functions for gene delivery and cellular imaging

Objectives: Technologies to increase tissue vascularity are critically important to the fields of tissue engineering and cardiovascular medicine. Angiogenic factors, like VEGF, have been widely investigated to induce vascular endothelial cell proliferation and angiogenesis for establishing a vascular network. However, effective transport of VEGF gene to target cells with minimal side effects remains a challenge despite the use of unique viral and non-viral delivery approaches.

Methods: This study presents a novel gene delivery system of fluorescein isothiocyanate (FITC) doped and poly(allylamine hydrochloride) (PAH) grafted Fe₃O₄@SiO₂ nanoparticles, which allows efficient loading of pVEGF to form Fe₃O₄@SiO₂(FITC)/PAH/pVEGF nanocomplexes for VEGF gene delivery and cellular imaging.

Results: The nanocomplexes maintain their superparamagnetic property in the silica composites at room temperature, reaching a saturation magnetization value of 5.19 emu/g of material, and no appreciable change in magnetism even after PAH modification. The quantitative analysis of cellular internalization into the living human umbilical vein endothelial cells (HUVECs) demonstrated that the Fe₃O₄@SiO₂(FITC)/PAH/pVEGF nanocomplexes could be entirely internalized by HUVECs, and exhibit high VEGF gene expression and an innocuous toxic profile. The magnetic resonance (MR) images showed that the superparamagnetic iron oxide core of Fe₃O₄@SiO₂(FITC)/PAH/pVEGF nanocomplexes could also act as a contrast agent for MR imaging. This property provides a benefit for monitoring gene delivery.

Conclusion: These data highlight multifunctional Fe₃O₄@SiO₂(FITC)/PAH/pVEGF nanocomplexes as an attractive platform for gene delivery of angiogenesis, and also making it a potential candidate of nanoprobes for cellular fluorescent imaging or MR imaging.     

A Functional Iron Oxide Nanoparticles Modified with PLA-PEG-DG as Tumor-Targeted MRI Contrast Agent

Purpose

Tumor targeting could greatly promote the performance of magnetic nanomaterials as MRI (Magnetic Resonance Imaging) agent for tumor diagnosis. Herein, we reported a novel magnetic nanoparticle modified with PLA (poly lactic acid)-PEG (polyethylene glycol)-DG (D-glucosamine) as Tumor-targeted MRI Contrast Agent.

Methods

In this work, we took use of the D-glucose passive targeting on tumor cells, combining it on PLA-PEG through amide reaction, and then wrapped the PLA-PEG-DG up to the Fe₃O₄@OA NPs. The stability and anti phagocytosis of Fe₃O₄@OA@PLA-PEG-DG was tested in vitro; the MRI efficiency and toxicity was also detected in vivo.

Results

These functional magnetic nanoparticles demonstrated good biocompatibility and stability both in vitro and in vivo. Cell experiments showed that Fe₃O₄@OA@PLA-PEG-DG nanoparticles exist good anti phagocytosis and high targetability. In vivo MRI images showed that the contrast effect of Fe₃O₄@OA@PLA-PEG-DG nanoparticles prevailed over the commercial non tumor-targeting magnetic nanomaterials MRI agent at a relatively low dose.

Conclusions

The DG can validly enhance the tumor-targetting effect of Fe₃O₄@OA@PLA-PEG nanoparticle. Maybe MRI agents with DG can hold promise as tumor-targetting development in the future.

     

Specific targeting of cancer cells by multifunctional mitoxantrone-conjugated magnetic nanoparticles

Abstract

We report on the synthesis of bifunctional mitoxantrone (MTX)-grafted magnetic nanoparticles (MNPs) modified by dopamine-polyethylene glycol-folic acid (DPA-PEG-FA) for targeted imaging and therapy of cancer. MNPs (～7–10?nm) were synthesized using the thermal decomposition reaction of Fe(acac)₃. Bromoacetyl (BrAc) terminal polyethylene glycol dopamine (DPA-PEG-BrAc) was synthesized and treated with ethylene diamine to form bifunctional PEG moiety containing dopamine at one end and amino group at the other end (i.e. DPA-PEG-NH₂). It was then reacted with Fe₃O₄ nanoparticles (NPs) to form Fe₃O₄-DPA-PEG-NH₂ NPs. The activated folic acid (FA) was chemically coupled to Fe₃O₄-DPA-PEG-NH₂, forming Fe₃O₄-DPA-PEG-FA. MTX was then conjugated to Fe₃O₄-DPA-PEG-FA, forming Fe₃O₄-DPA-PEG-FA-MTX. Physicochemical characteristics of the engineered MNPs were determined. The particle size analysis and electron microscopy showed an average size of ～35?nm for Fe₃O₄-DPA-PEG-FA-MTX NPs with superparamagnetic behavior. FT-IR spectrophotometry analysis confirmed the conjugation of FA and MTX onto the MNPs. Fluorescence microscopy, cytotoxicity assay and flow cytometry analysis revealed that the engineered Fe₃O₄-DPA-PEG-FA-MTX NPs were able to specifically bind to and significantly inhibit the folate receptor (FR)-positive MCF-7 cells, but not the FR-negative A549 cells. Based upon these findings, we suggest the Fe₃O₄-DPA-PEG-FA-MTX NPs as an effective multifunctional-targeted nanomedicine toward simultaneous imaging and therapy of FR-positive cancers.     

Synthesis and in vitro study of cisplatin-loaded Fe3O4 nanoparticles modified with PLGA-PEG6000 copolymers in treatment of lung cancer

Abstract

In the field of cancer therapy, magnetic nanoparticles modified with biocompatible copolymers are promising vehicles for the delivery of hydrophobic drugs such as Cisplatin. The major aim of this effort was to evaluate whether Cisplatin-Encapsulated magnetic nanoparticles improved the anti-tumour effect of free Cisplatin in lung cancer cells. The PLGA-PEG triblock copolymer was synthesised by ring-opening polymerisation of d,l-lactide and glycolide with polyethylene glycol (PEG₆₀₀₀) as an initiator. The bulk properties of these copolymers were characterised using Fourier transform infrared spectroscopy. Cisplatin-loaded nanoparticles (NPs) were prepared by double emulsion solvent evaporation technique and were characterised for size, drug entrapment efficiency (%), drug content (% w/w), and surface morphology. In vitro release profile of cisplatin-loaded NP formulations was determined. Cytotoxic assays were evaluated in lung carcinoma (A549)-treated cells by the MTT assay technique. In addition, the particles were characterised by X-ray powder diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. The anti-proliferative effect of Cisplatin appeared much earlier when the drug was encapsulated in magnetic nanoparticles than when it was free. Cisplatin-Encapsulated magnetic nanoparticles significantly enhanced the decrease in IC50 rate. The in vitro cytotoxicity test showed that the Fe₃O₄-PLGA-PEG₆₀₀₀ magnetic nanoparticles had no cytotoxicity and were biocompatible. The chemotherapeutic effect of free Cisplatin on lung cancer cells is improved by its encapsulation in modified magnetic nanoparticles. This approach has the prospective to overcome some major limitations of conventional chemotherapy and may be a promising strategy for future applications in lung cancer therapy.     

Anionic polymers and 10 nm Fe3O4@UA wound dressings support human foetal stem cells normal development and exhibit great antimicrobial properties

The aims of this study were the development, characterization and bioevaluation of a novel biocompatible, resorbable and bio-active wound dressing prototype, based on anionic polymers (sodium alginate – AlgNa, carboximethylcellulose – CMC) and magnetic nanoparticles loaded with usnic acid (Fe₃O₄@UA). The antimicrobial activity was tested against Staphylococcus aureus grown in biofilms. The biocompatibility testing model included an endothelial cell line from human umbilical vein and human foetal progenitor cells derived from the amniotic fluid, that express a wide spectrum of surface molecules involved in different vascular functions and inflammatory response, and may be used as skin regenerative support. The obtained results demonstrated that CMC/Fe₃O₄@UA and AlgNa/Fe₃O₄@UA are exhibiting structural and functional properties that recommend them for further applications in the biomedical field. They could be used alone or coated with different bio-active compounds, such as Fe₃O₄@UA, for the development of novel, multifunctional porous materials used in tissues regeneration, as antimicrobial substances releasing devices, providing also a mechanical support for the eukaryotic cells adhesion, and exhibiting the advantage of low cytotoxicity on human progenitor cells. The great antimicrobial properties exhibited by the newly synthesized nano-bioactive coatings are recommending them as successful candidates for improving the implanted devices surfaces used in regenerative medicine.     

Phospholipid micelle-based magneto-plasmonic nanoformulation for magnetic field-directed,imaging-guided photo-induced cancer therapy

We present a magnetoplasmonic nanoplatform combining gold nanorods (GNR) and iron-oxide nanoparticles within phospholipid-based polymeric nanomicelles (PGRFe). The gold nanorods exhibit plasmon resonance absorbance at near infrared wavelengths to enable photoacoustic imaging and photothermal therapy, while the Fe₃O₄ nanoparticles enable magnetophoretic control of the nanoformulation. The fabricated nanoformulation can be directed and concentrated by an external magnetic field, which provides enhancement of a photoacoustic signal. Application of an external field also leads to enhanced uptake of the magnetoplasmonic formulation by cancer cells in vitro. Under laser irradiation at the wavelength of the GNR absorption peak, the PGRFe formulation efficiently generates plasmonic nanobubbles within cancer cells, as visualized by confocal microscopy, causing cell destruction. The combined magnetic and plasmonic functionalities of the nanoplatform enable magnetic field-directed, imaging-guided, enhanced photo-induced cancer therapy.From the Clinical EditorIn this study, a nano-formulation of gold nanorods and iron oxide nanoparticles is presented using a phospholipid micelle-based delivery system for magnetic field-directed and imaging-guided photo-induced cancer therapy. The gold nanorods enable photoacoustic imaging and photothermal therapy, while the Fe₃O₄ nanoparticles enable magnetophoretic control of the formulation. This and similar systems could enable more precise and efficient cancer therapy, hopefully in the near future, after additional testing.     

Preparation and characterization of poly(methyl methacrylate)—iron (III) oxide microparticles using a modified solvent evaporation method

At present, there is widespread interest in developing new, biocompatible microparticles made from polymers such as poly(methyl methacrylate) (PMMA) that could have applications ranging from diagnostic imaging to drug delivery. In these experiments, there were two primary objectives: (1) to stabilize a suspension of iron (III) oxide (α-Fe₂O₃; mean diameter?=?100?nm) nanoparticles in a solution of PMMA by using an emulsifier and different mixtures of two miscible solvents; and (2) to fabricate PMMA-α-Fe₂O₃ microparticles by using an oil-in-water (o/w) solvent evaporation method. By accomplishing the first objective, it was hypothesized that the encapsulation efficiency of α-Fe₂O₃ within PMMA microparticles would improve and induce the clustering of α-Fe₂O₃ along the circumferential edges of the microparticles. Of the seven emulsifiers tested, Tween 80 was selected primarily for its hydrophilicity and its ability to produce a stable α-Fe₂O₃ dispersion. As a result, 22 batches of microspheres (11 with Tween 80 and 11 without) were made and the solvent (dichloromethane) to co-solvent (ethyl acetate) ratios were varied. Particles made with solvent mixtures of >50% ethyl acetate (<50% dichloromethane) were more likely to be hollow and had larger mean volumetric particle diameters (>5 microns) than particles made with mixtures containing >50% dichloromethane. Particles made with Tween 80 were larger, more porous, and had α-Fe₂O₃ aligned along the circumferential edges of the particles. The use of solvent mixtures did not improve the encapsulation efficiency of α-Fe₂O₃ but the use of ethyl acetate helped to induce the clustering of α-Fe₂O₃ along the peripheries of the microparticles.     

Evaluation of Nanodispersion of Iron Oxides Using Various Polymers

In order to create Fe₂O₃ and Fe₂O₃·H₂O nanoparticles, various polymers were used as dispersing agents, and the resulting effects on the dispersibility and nanoparticulation of the iron oxides were evaluated. It was revealed that not only the solution viscosity but also the molecular length of the polymers and the surface tension of the particles affected the dispersibility of Fe₂O₃ and Fe₂O₃·H₂O particles. Using the dispersing agents 7.5% hydroxypropylcellulose-SSL, 6.0% Pharmacoat 603, 5.0% and 6.5% Pharmacoat 904 and 7.0% Metolose SM-4, Fe₂O₃ nanoparticles were successfully fabricated by wet milling using Ultra Apex Mill. Fe₂O₃·H₂O nanoparticles could also be produced using 5.0% hydroxypropylcellulose-SSL and 4.0 and 7.0% Pharmacoat 904. The index for dispersibility developed in this study appears to be an effective indicator of success in fabricating nanoparticles of iron oxides by wet milling using Ultra Apex Mill.