Polymeric Magnetic Nanoparticles Research Articles

Development of Molecularly Imprinted Magnetic Amino Acid-Based Nanoparticles for Voltammetric Analysis of Lead Ions in Honey.

Lead (Pb) is a hazardous metal that poses a significant threat to both the environment and human health. The presence of Pb in food products such as honey can pose a significant risk to human health and is therefore important to detect and monitor. In this study, we propose a voltammetric detection method using molecularly imprinted polymer (MIP) electrodes to detect Pb (II) ions in honey. Pb (II) ion-imprinted amino acid-based nanoparticles with magnetic properties on a carbon paste electrode (MIP-CPE) were designed to have high sensitivity and selectivity towards Pb (II) ions in the honey sample. Zetasizer measurements, electron spin resonance, and scanning electron microscopy were used to characterize magnetic polymeric nanoparticles. The results showed that the voltammetric detection method using MIP-CPE was able to accurately detect Pb (II) ions in honey samples with a low detection limit. The proposed method offers a simple, rapid, cost-effective solution for detecting Pb (II) ions in honey. It could potentially be applied to other food products to ensure their safety for human consumption. The MIP-CPE sensor was designed to have high sensitivity and selectivity towards Pb (II) ions in the honey sample. The results showed that the technique was able to deliver highly sensitive results since seven different concentrations were prepared and detected to obtain an R2 of 0.9954, in addition to a low detection limit (LOD) of 0.0912 µM and a low quantification limit (LOQ) of 0.276 µM. Importantly, the analysis revealed no trace of Pb (II) ions in the honey samples obtained from Cyprus.

Affinity-Based Magnetic Nanoparticle Development for Cancer Stem Cell Isolation.

Cancer is still the leading cause of death in the world despite the developing research and treatment opportunities. Failure of these treatments is generally associated with cancer stem cells (CSCs), which cause metastasis and are defined by their resistance to radio- and chemotherapy. Although known stem cell isolation methods are not sufficient for CSC isolation, they also bring a burden in terms of cost. The aim of this study is to develop a high-efficiency, low-cost, specific method for cancer stem cell isolation with magnetic functional nanoparticles. This study, unlike the stem cell isolation techniques (MACS, FACS) used today, was aimed to isolate cancer stem cells (separation of CD133+ cells) with nanoparticles with specific affinity and modification properties. For this purpose, affinity-based magnetic nanoparticles were synthesized and characterized by providing surface activity and chemical reactivity, as well as making surface modifications necessary for both lectin affinity and metal affinity interactions. In the other part of the study, synthesized and characterized functional polymeric magnetic nanoparticles were used for the isolation of CSC from the human osteosarcoma cancer cell line (SAOS-2) with a cancer stem cell subpopulation bearing the CD133 surface marker. The success and efficiency of separation after stem cell isolation were evaluated via the MACS and FACS methods. As a result, when the His-graft-mg-p(HEMA) nanoparticle was used at a concentration of 0.1 µg/mL for 106 and 108 cells, superior separation efficiency to commercial microbeads was obtained.

ZnFe2O4@SiO2@L-Lisin@Cr-EDTA coordination polymer: A novel, green, magnetic, reusable, and versatile nanocatalyst for the oxidation of sulphides

In this research, the design, and synthesis of ZnFe2O4@SiO2@L-Lisin@Cr-EDTA coordination polymer magnetic nanoparticles as a novel, recyclable, and heterogeneous catalyst was developed. EDTA with four carboxylic groups as an outstanding chelating agent was utilized for the preparation of the Cr-EDTA metal-organic framework (Cr-EDTA coordination polymer). In the next step, by immobilizing the synthesized Cr-EDTA coordination polymer on the surface of the Zinc ferrite nanoparticles, ZnFe2O4@SiO2@L-Lisin@Cr-EDTA coordination polymer was synthesized. The magnetic nanocatalyst (ZnFe2O4@SiO2@L-Lisin@Cr-EDTA coordination polymer) was characterized by using various methods such as BET, FTIR, SEM, XRD, EDX, TGA, VSM, and Map analysis. Also, the oxidation of sulfides to sulfoxide was efficiently performed using the ZnFe2O4@SiO2@L-Lisin@Cr-EDTA coordination polymer catalytic system. The synthesized catalyst can be reused for five periods without loss of catalytic activity.

Preparation and characterization of various PVPylated divalent metal-doped ferrite nanoparticles for magnetic hyperthermia.

There is an incessant demand to keep improving on the heating responses of polymeric magnetic nanoparticles (MNPs) under magnetic excitation, particularly in the pursuit for them to be utilized for clinical hyperthermia applications. Herein, we report the fabrication of a panel of PVP-capped divalent metal-doped MFe2O4 (M ≅ Co, Ni, Zn, Mg, and Sn) MNPs prepared via the Ko-precipitation Hydrolytic Basic (KHB) methodology and assess their magneto-thermal abilities. The physiochemical, structural, morphological, compositional, and magnetic properties of the doped ferrites were fully characterized using various techniques mainly TEM, XRD, EDX, FTIR, and VSM. The obtained doped MNPs exhibited stabilized quasi-spherical sized particles (10-17 nm), pure well-crystallized cubic spinel phases, and high saturation magnetizations (Ms = 26-81 emu g-1). In response to a clinically-safe alternating magnetic field (AMF) (f = 332.8 kHz and H = 170 Oe), distinctive heating responses of these doped ferrites were attained. Hyperthermia temperatures of 42 °C can be reached very fast in only ∼5 min, with heating temperatures slowly increasing to reach up to 55 °C. The highest heating performance was observed for PVP-NiFe2O4 and the lowest for PVP-Sn-doped NPs (SAR values: PVP-NiFe2O4 > PVP-CoFe2O4 > PVP-ZnFe2O4 > PVP-MgFe2O4 > PVP-SnFe2O4). This trend was found to be directly correlated to their observed magnetic saturation and anisotropy. Heating efficiencies and specific SAR values as functions of concentration, frequency, and amplitude were also systematically investigated. Finally, cytotoxicity assay was conducted on aqueous dispersions of the doped ferrite NPs, proving their biocompatibility and safety profiles. The PVPylated metal-doped ferrite NPs prepared here, particularly Ni- and Co-doped ferrites, are promising vehicles for potential combined magnetically-triggered biomedical hyperthermia applications.

Design and synthesis of biologically inspired biocompatible various polymeric magnetic nanoparticles for imaging and biomedical applications

Highly monodispersed magnetite nanoparticles with controlled particle size and surface coatings have been successfully synthesized as a model system to investigate the effect of the surface coating on the magnetic properties. In this study, iron oxide (Fe3O4) magnetic nanoparticles (MNPs) were modified with polyethylene glycol (PEG), polyvinyl alcohol (PVA), poly(N-vinyl pyrrolidone) (PVP) and oleic acid coatings, templates and stabilizers to synthesise Fe3O4 nanoparticles through the co-precipitation method. The resultant magnetic nanoparticles were characterized by TEM, FTIR, XRD, Zeta, VSM and NMR analyses to evaluate their physical and magnetic properties. The obtained Fe3O4, Fe3O4 @PEG400, Fe3O4 @PEG6000, Fe3O4 @PVP, Fe3O4 @PVA and Fe3O4 @oleic acid MNPs showed T2 contrast performance with r2 relaxivities of 60.62, 37.37, 1502.40, 1641.99, 4875.63 and 114.01 mM s-1. The cell viability assay exhibited good biocompatibility.

Thermo-responsive-polymeric-gates of poly(N-isopropylacrylamide)/N-(hydroxymethyl)acrylamide coated magnetic nanoparticles as a synergistic approach to cancer therapy: Drug release and kinetics models of chemothermal magnetic nanoparticles

The study presents a controlled nanoscale drug delivery system mediated by polymeric magnetic nanoparticles. Under an alternating magnetic field (AMF), the magnetic nanoparticles act as internal heating sources that increase the surrounding temperature, provoking polymer transitions and thereby releasing the entrapped drug. We explain the drug-release mechanism using different mathematical models including Higuchi, Korsmeyer–Peppas, Hixson–Crowell, and Kopcha. Our results indicate that doxorubicin (DOX) release follows the Hixson–Crowell model with R2 = 0.99, revealing that the changes in the surface areas of the particles are the main driving force for drug release from poly(N-isopropylacrylamide)/N (hydroxymethyl) acrylamide coated SPIONs (SPNH/DOX) at 43 °C. However, at 37 °C, the drug release occurs by the diffusion mechanism. Moreover, in vitro cell culture assays including CCK-8, FACS, confocal and BIO-TEM images have confirmed cytotoxicity and cellular uptake of SPNH/DOX in CT26 cancer cells. Through a synergetic effect between chemotherapy triggered by AMF application and intracellular hyperthermia, significant tumoricidal effects were achieved in the initial 24 h after treatment.

Preparation and characterization of PLGA-based magnetic polymer nanoparticles for targeting pancreatic adenocarcinoma.

This study aims to develop a novel tumor-targeted molecular probe for pancreatic cancer imaging. The objective of this is to prepare a CKAAKN peptide-conjugated poly (lactic-co-glycolic acid)-poly (ethylene glycol) amphiphilic polymer (CKAAKN-PEG-PLGA) for the tumor-targeted delivery of magnetic resonance imaging (MRI) contrast agent ultrasmall superparamagnetic iron oxide (USPIO). The early diagnosis of pancreatic cancer is crucial for improving its prognosis, but the clinical application of many diagnostic methods is limited owing to a lack of specificity and sensitivity. Methods CKAAKN-PEG-PLGA was synthesized by the amidation reaction. USPIO-loaded polymeric magnetic nanoparticles (USPIO@CKAAKN-PEG-PLGA) were prepared by the emulsion solvent evaporation method. The in vitro tumor targeting and bio-safety of nanoparticles were evaluated by targeted cellular uptake, MR imaging and MTT assay. Results USPIO@CKAAKN-PEG-PLGA nanoparticles showed excellent biosafety with an average diameter of 104.5 ± 4.1 nm. Modification of CKAAKN peptide could improve USPIO binding ability to internalize into CKAAKN-positive BxPC-3 cells compared with non-targeting nanoparticles and the control group. The relative fluorescence intensity in BxPC-3 and HPDE6-C7 cells was 23.77 ± 4.18 and 6.44 ± 2.10 (p＜0.01), and respectively became 16.13 ± 0.83 and 11.74 ± 1.74 after the addition of free CKAAKN peptide. In vitro MR imaging studies showed that an obvious decrease in the signal intensity was observed in the targeted nanoparticles group incubated with BxPC-3 and HPDE6-C7 cells (P<0.05). Conclusion USPIO@CKAAKN-PEG-PLGA nanoparticles could significantly enhance the tumor specificity of USPIO in CKAAKN-positive pancreatic cancer cell BxPC-3, which is expected as a promising candidate of MRI contrast enhancement for the early diagnosis of pancreatic cancer.

Preparation and characterization of chitosan/polyethylene glycol and cobalt ferrite magnetic-polymeric nanoparticles as resveratrol carriers: preparation, analytical methodology validation and in vitro applicability

ABSTRACT The objective of this research was to produce, characterize and evaluate biological activities of magnetic-polymeric nanoparticles loaded with resveratrol. Magnetic nanoparticles of cobalt ferrite (CoFe2O4), polymeric nanoparticles of chitosan (CS) and polyethylene glycol (PEG), and polymeric-magnetic nanoparticles containing resveratrol (RSV) were developed. An analytical method using UV-VIS spectroscopy was developed and validated for the determination of RSV in the nanoparticles. The samples were analyzed by dynamic light scattering (DLS) for size, polydispersity index (PDI) and zeta potential. The encapsulation efficiency was determined by an indirect method. Antioxidants (ABTS and DPPH) and antibacterial (MIC and CBM) activities were evaluated. The average size of the nanoparticles varied between 184.6 and 276.5 nm. The magnetic-polymeric nanoparticles showed high encapsulation efficiency (EE) (98.75%) with a slow and prolonged release rate of 33.49% in 120 h. Furthermore, three months of storage showed less than 10% of RSV degradation. Its antioxidant activity (AA) was 170.55 mmol TE g−1 (by the ABTS method) and 130.60 mmol TE g−1 (by the DPPH method). The resveratrol-loaded magnetic-polymeric nanoparticles inhibited the growth of four tested bacteria. Their MIC values were less than 52.36 µg mL−1, and the CBM values of the nanoparticles >52.36 µg mL−1.

Green synthesis of lignin-based nanoparticles as a bio-carrier for targeted delivery in cancer therapy

Polymeric magnetic nanoparticles have shown higher efficacy in cancer diagnosis and treatment than conventional chemotherapies. Lignin is an abundantly available natural polymer that can be selectively modified using a rapidly expanding toolkit of biocatalytic and chemical reactions to yield ‘intelligent’ theranostic-nanoprobes. We aim to valorize lignin to develop a natural polymeric-magnetic-nano-system for the targeted delivery of methotrexate. In the current study, we synthesized nanoparticles of lignin and iron oxide with methotrexate using a new approach of anti-solvent precipitation with ultrasonication. The ensuing nanoparticles are magnetic, smooth, polyhedral with characteristic dimension of 110-130 nm. The drug loading and encapsulation efficiencies were calculated to be 66.06 % and 64.88 %, respectively. The nanoparticles exhibit a concentration-dependent release of methotrexate for the initial 24 h, followed by sustained release. Moreover, formulation is non-hemolytic and scavenges radicals owing to the antioxidant property of lignin. Additionally, methotrexate delivered using the nanoparticles exhibited higher cytotoxicity in cellular-viability assays employing breast cancer and macrophage cell lines compared to the pure form of the drug. Synergistic action of lignin, iron oxide, and methotrexate contribute to enhanced caspase-3 activity and reduced glutathione levels in the breast cancer cells, as well as elevated internalization of the drug on account of increased receptor-mediated endocytosis.

Magnetic nanopromoter enables excellent kinetic promotion and cycling performance in methane hydrate formation

Among several promising applications of gas hydrate-based technologies, storage and transportation of gases (H2, CH4, CO2, etc.) in the form of hydrate has aroused extensive concern. Currently, developing an effective and recyclable promoter holds the key to achieving the industrial application of hydrates. Herein, we proposed sulfonated magnetic polymer nanoparticles as the promoter for methane hydrate formation, which are synthesized by sulfonating the magnetic Fe3O4 particle in the soap-free emulsion system. Then the performance of the promoter was evaluated with regard to induction time, reaction time, and storage capacity at different concentrations. Hydrate formation results showed that when the mass concentration was 20 g/L, the storage capacity can reach up to 137.0 ± 2.8 v/v with the reaction time of 28 min while the induction time was only with the range of 44.1 ± 13.52 min. Further, the hydrate structure (sI) and dynamic occupancy change of 51262 and 512 cage were studied by the in-situ Raman at micro level and meanwhile the macroscopic morphology observation was also conducted. In addition to the high performance described above, the promoter also exhibited high-performance reliability in 15 cycles of hydrate formation experiments. This indicates that the promoter has great promise on economic benefit, environmental friendliness and recyclability for application in the methane hydrate-based technology.

Engineered Magnetic Polymer Nanoparticles Can Ameliorate Breast Cancer Treatment Inducing Pyroptosis-Starvation along with Chemotherapy.

Nanotechnology has shown a revolution in cancer treatments, including breast cancers. However, there remain some challenges and translational hurdles. Surgery, radiotherapy, and chemotherapy are the primary treatment methods for breast cancer, although drug combinations showed promising results in preclinical studies. Herein we report the development of a smart drug delivery system (DDS) to efficiently treat breast cancer by pyroptosis-starvation-chemotherapeutic combination. Cancer-starvation agent glucose oxidase was chemically attached to synthesized iron oxide nanoparticles which were entrapped inside poly(lactic-co-glycolic acid) along with apoptosis-associated speck-like protein containing a caspase recruitment domain plasmid and paclitaxel (PTX). An emulsion solvent evaporation method was used to prepare the DDS. The surface of the DDS was modified with chitosan to which aptamer was attached to achieve site-specific targeting. Hence, the prepared DDS could be targeted to a tumor site by both external magnet and aptamer to obtain an enhanced accumulation of drugs at the tumor site. The final size of the aptamer-decorated DDS was less than 200 nm, and the encapsulation efficiency of PTX was 76.5 ± 2.5%. Drug release from the developed DDS was much higher at pH 5.5 than at pH 7.4, ensuring the pH sensitivity of the DDS. Due to efficient dual targeting of the DDS, in vitro viability of 4T1 cells was reduced to 12.1 ± 1.6%, whereas the nontargeted group and free PTX group could reduce the viability of cells to 29.2 ± 2.4 and 46.2 ± 1.6%, respectively. Our DDS showed a synergistic effect in vitro and no severe side effects in vivo. This DDS has strong potential to treat various cancers.

Utilization of Sulfonated Waste Polystyrene-Based Cobalt Ferrite Magnetic Nanocomposites for Efficient Degradation of Calcon Dye.

We presented a simple and efficient method for making a polymer–metal nanocomposite using various amounts of cobalt ferrite magnetic nanoparticles (CoFe2O4 MNp) with sulfonated waste polystyrene (SWPS) and utilized for Calcon dye degradation. The MNp was encapsulated with SWPS to avoid agglomeration and maintain its smaller size. ATR-FTIR, Raman spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), dynamic light scattering (DLS), field emission scanning electron microscopy (FESEM), high-resolution transmittance electron microscopy (HR-TEM), atomic force microscopy (AFM) and solid UV were used to analyze the produced polymeric magnetic nanoparticles (SWPS/MNp). As the MNp loading increases, the average particle size decreases. For Calcon dye degradation, SWPS/MNp (20 wt%) was utilized with a smaller average particle size, and the structural changes were detected using a UV-Vis spectrophotometer. As a result, the Calcon dye’s characteristic absorbance peak at 515 nm was red-shifted to 536 and 565 nm after 5 min, resulting in a color shift from dark brown to light blue that could be seen with the naked eye. A strong linear correlation was found between the red-shifted absorbance and the concentration of dye solution over the range of 10–100 ppm under optimal conditions. The proposed dye degradation process is simple, efficient, and environmentally friendly and has been successfully used to purify organic azo-dye-containing water.

Decorated magnetic nanoparticles with polyvinyl alcohol brushes modified with metal chelate affinity groups for purification of proteins.

Refining is a serious challenge in the production of recombinant proteins, and this study proposes a new and easy strategy for the synthesis of magnetic affinity nanoparticles. First, the nanoparticles attached to polyvinyl alcohol brushes were synthesized, and then the hydroxyl groups of this polymer were converted to chelate groups. The nanoparticles were examined by (SEM) scanning electron microscopy, (TEM) transmission electron microscopy, (DLS) dynamic light scattering, (FT-IR) Fourier transform infrared, (XRD) X-ray powder diffraction, (VSM) vibrating sample magnetometry, and (TGA) thermal gravimetric analysis. The results confirm that uniform and spherical magnetic polymer nanoparticles with high magnetization and superparamagnetic properties were successfully synthesized. The S100A9 protein, a His-tagged recombinant protein, was expressed and purified using the synthesized nanoparticles. According to the (SDS-PAGE) sulfate-polyacrylamide gel electrophoresis results, there is a high degree of resolution in protein separation. The synthesized nanoparticles have a high protein binding capacity of about 208 mg of protein per gram of nanoparticles.

Synthesis of ginsenoside Rb1-imprinted magnetic polymer nanoparticles for the extraction and cellular delivery of therapeutic ginsenosides

BackgroundPanax ginseng (ginseng) is a traditional medicine that is reported to have cardioprotective effects; ginsenosides are the major bioactive compounds in the ginseng root. MethodsMagnetic molecularly imprinted polymer (MMIP) nanoparticles might be useful for both the extraction of the targeted (imprinted) molecules, and for the delivery of those molecules to cells. In this work, plant growth regulators were used to enhance the adventitious rooting of ginseng root callus; imprinted polymeric particles were synthesized for the extraction of ginsenoside Rb1 from root extracts, and then employed for subsequent particle-mediated delivery to cardiomyocytes to mitigate hypoxia/reoxygenation injury. ResultsThese synthesized composite nanoparticles were first characterized by their specific surface area, adsorption capacity, and magnetization, and then used for the extraction of ginsenoside Rb1 from a crude extract of ginseng roots. The ginsenoside-loaded MMIPs were then shown to have protective effects on mitochondrial membrane potential and cellular viability for H9c2 cells treated with CoCl2 to mimic hypoxia injury. The protective effect of the ginsenosides was assessed by staining with JC-1 dye to monitor the mitochondrial membrane potential. ConclusionMMIPs can play a dual role in both the extraction and cellular delivery of therapeutic ginsenosides.

Polymeric magnetic nanoparticles: a multitargeting approach for brain tumour therapy and imaging.

The most challenging task in targeting the brain is trespassing the blood-brain barrier (BBB) which restricts the movement of about 98% small molecules. Targeting the central nervous system using magnetic nanoparticles may deliver the drug to the target site along with a contrast imaging property. The use of magnetic nanoparticles can become non-invasive drug targeting and a bio-imaging method for brain cancer. The strategy to apply polymeric nanoparticles as a carrier of magnetic iron oxide nanoparticles can be a promising tool as a multitherapeutic drug delivery approach involving delivery of chemotherapeutic drugs with a magnetic targeting approach, imaging, and hyperthermia. This review will highlight the existing difficulties/barriers in crossing the BBB, types of magnetic materials, polymeric carriers for functionalization of magnetic nanoparticles, and targeting strategies as therapeutic and imaging modalities. Utilization of polymeric magnetic nanoparticles as an efficient targeting platform for better drug delivery and imaging for brain cancer and future prospects are also discussed. Polymeric magnetic nanoparticles as a drug delivery and bio-imaging vehicle for brain cancer.

GRGDS-conjugated and curcumin-loaded magnetic polymeric nanoparticles for the hyperthermia treatment of glioblastoma cells

Thermally responsive and ligand-mediated drug delivery systems have the potential to improve the treatment of brain tumors, especially, most lethal one, glioblastoma multiform (GBM). Magnetic nanoparticle-mediated hyperthermia becomes one of the most promising alternative therapy for GBM treatment in cases where localized heating and targeted delivery of a therapeutic drug can be achieved on the tumor site. In this study, it is aimed to increase the therapeutic efficiency of multi-functionalized nanoparticles (NPs) in combination with radiofrequency hyperthermia (RF-HT) on GBM cells. For this purpose, firstly, a low-cost and portable home-built RF-HT system suitable for in vitro/in vivo studies was successfully implemented and tested at 13.56 MHz frequency with power up to approximately 400 W. Subsequently, the highly monodispersed superparamagnetic iron oxide nanoparticles (SPIONs), which could interact with the RF magnetic field, were synthesized with the mean particle size of 5.6 ± 0.9 nm. The obtained SPIONs were coated with poly (lactic-co-glycolic acid)-poly (ethylene glycol) di-block copolymer (PLGA-b-PEG). Most of the SPIONs were uniformly distributed in such a well-defined spherical-shaped polymeric NP. Moreover, curcumin (Cur), a potential agent for GBM treatment, was loaded into the magnetic polymeric nanoparticles (m-PNPs) with a loading capacity of 8% (w/w, Cur/NPs) and a mean diameter of Cur-loaded m-PNPs (Cur-m-PNPs) was 142 ± 70 nm. To increase cellular uptake and targeting ability of NPs, glycine-arginine-glycine-aspartic acid-serine (GRGDS) peptide was immobilized on the Cur-m-PNPs and the amount of GRGDS was detected as 37 µg/mg NPs. In vitro cytotoxicity studies revealed that the presence of GRGDS on Cur-m-PNPs (GRGDS-Cur-m-PNPs) improved the cytotoxic efficiency of Cur-m-PNPs by 6-fold in GBM cells for all incubation times (24, 48 and 72 h). Furthermore, NPs with RF treatment exhibited higher antitumor activity than that of NPs without RF on GBM cells. This result may be attributed to the thermal (SPIONs) or non-thermal (cellular membrane) effects or both of them on cells. Overall, this study showed that RF-HT in combination with GRGDS-Cur-m-PNPs could provide a feasible approach to improve GBM treatment.

Formulation and characterization of oleic acid magnetic PEG PLGA nanoparticles for targeting glioblastoma multiforme

Glioblastoma multiforme (GBM) is the most common and malignant form of astrocytoma with a median survival time of 1–2 years after diagnosis. The major treatment hurdle is the limited delivery of drugs to the brain due to the insurmountable blood brain barrier (BBB). Literature review reveals that nanoparticulate delivery system, in particular, magnetic polymeric nanoparticles in the presence of an external magnetic field may have enhanced permeation across the BBB. Therefore, the objective of this study was to fabricate the core of the polymeric nanoparticles with magnetic property. This core was fabricated by a modified seed synthesis method using tris(acetylacetonate) iron (III) [Fe(acac)3] as a precursor. To prevent the oxidation of Fe(acac)3, an overcoating with oleic acid was performed. The resulting oleic acid magnetic nanoparticle (OAMNP) was successfully prepared with a yield of 187.5 ± 4.2 mg. The particle size of the core was 9 ± 0.3 nm with a polydispersity index (PDI) of 0.189 ± 0.001. OAMNP was dispersed within the polymeric matrix comprising of poly(lactic acid)–methoxy poly(ethylene oxide) (PLA–PEG) and poly(lactic-co-glycolic acid) (PLGA) (PEG PLGA) by single emulsion solvent evaporation technique. The resulting nanoparticle had a particle size of 201 ± 2.1 nm with a PDI of 0.197 ± 0.003. The presence of co-polymer block linkage on the surface of OAMNP was qualitatively confirmed by proton NMR and FT-IR analysis. The mean entrapment efficiency of OAMNP within the PEG PLGA matrix was 43%. The iron concentration was 60 ± 3.1 µg/ml which was below is cytotoxic concentration, and in line with published literature. Furthermore, in the presence of an external magnetic field superior efficacy of OAMNP PEG PLGA NPS in U-138 cells was observed.

Smart Nanoformulation Based on Polymeric Magnetic Nanoparticles and Vincristine Drug: A Novel Therapy for Apoptotic Gene Expression in Tumors.

Background: Advanced nanobiotechnology provides safe and efficient drug delivery systems to deliver chemotherapy that targets cancer cells efficiently. Methods: A polymeric-magnetic nanocarrier was composed of a dextran (DEX) shell, a superparamagnetic iron oxide (SPION) core and was conjugated with folate (FA) to carry the anticancer drug vincristine (VNC) in Tera-1 testicular tumor cells. The molecular mechanisms by which apoptosis was induced were analyzed using flow cytometry and qPCR, which exhibited anticancer activity of nanoparticles (NPs). Results: This nanocarrier revealed a controlled release of VNC in citrate and phosphate buffer solutions that were maintained at pH 5.5 and pH 7.4, respectively. The Inhibitory concentration (IC50) values were greater than 5 mg/mL and displayed ten times higher cytotoxicity than the comparable free drug concentration. The Caspase-9 and P53 expressions were increased, whereas P21 and AKt1 decreased noticeably in the treated cells. The results point to the possible activation of apoptosis following treatment with NPs loaded with vincristine.

A Biomimetic Polymer Magnetic Nanocarrier Polarizing Tumor-Associated Macrophages for Potentiating Immunotherapy.

The progress of antitumor immunotherapy is usually limited by tumor-associated macrophages (TAMs) that account for the highest proportion of immunosuppressive cells in the tumor microenvironment, and the TAMs can also be reversed by modulating the M2-like phenotype. Herein, a biomimetic polymer magnetic nanocarrier is developed with selectively targeting and polarizing TAMs for potentiating immunotherapy of breast cancer. This nanocarrier PLGA-ION-R837 @ M (PIR @ M) is achieved, first, by the fabrication of magnetic polymer nanoparticles (NPs) encapsulating Fe3 O4 NPs and Toll-like receptor 7 (TLR7) agonist imiquimod (R837) and, second, by the coating of the lipopolysaccharide (LPS)- treated macrophage membranes on the surface of the NPs for targeting TAMs. The intracellular uptake of the PIR @ M can greatly polarize TAMs from M2 to antitumor M1 phenotype with the synergy of Fe3 O4 NPs and R837. The relevant mechanism of the polarization is deeply studied through analyzing the mRNA expression of the signaling pathways. Different from previous reports, the polarization is ascribed to the fact that Fe3 O4 NPs mainly activate the IRF5 signaling pathway via iron ions instead of the reactive oxygen species-induced NF-κB signaling pathway. The anticancer effect can be effectively enhanced through potentiating immunotherapy by the polarization of the TAMs in the combination of Fe3 O4 NPs and R837.

Triazine-Based Polymeric Network-Modified Magnetic Nanoparticles (NPs) as an Efficient Sorbent to Extract 1-Naphthylacetic Acid in Fruit and Vegetable Samples

In this study, a triazine-based polymeric network-modified magnetic nanoparticles (TPN/MNPs) was synthesized and applied as adsorbent for extraction of 1-naphthylacetic acid (NAA) from the fruit and vegetable samples followed by HPLC determination. The synthesized TPN/MNPs were characterized by the vibrating sample magnetometry (VSM), Fourier-transform infrared spectroscopy (FT-IR), field emission-scanning electron microscopy (FE-SEM) and thermogravimetric analysis (TGA). The factors influencing the extraction efficiency including pH, sorbent amount, salt concentration, extraction time, sample volume and desorption conditions were studied and optimized. Under the optimal conditions, good linearity was obtained in the range of 1.0–500 µg L−1. The limit of detection (LOD) and limit of quantification (LOQ) were 0.3 µg L−1 and 1.0 µg L−1, respectively. The relative standard deviations (RSDs) of intra-day and inter-day were less than 9.5% at 10 and 100 µg L−1 of NAA. The method was successfully applied for extraction and determination of NAA in the fruit and vegetable samples including cucumber, tomato and apple and good recoveries were obtained (94.5–96.5%).