Green synthesis and characterization of iron oxide nanoparticles using Coriandrum sativum L. leaf extract

Green nanoparticle synthesis is a promising, eco-friendly and safe approach. In the current study, Iron oxide nanoparticles (FeONPs) were synthesized using aqueous leaf extract of Coriandrum sativum L. Further, the characterization of synthesized FeONPs was performed using ultraviolet-visible spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), vibrating sample magnetometer (VSM) and differential scanning colorimetry (DSC). The surface plasmon resonance effect confirmed the synthesis of FeONPs. Dynamic light scattering (DLS) revealed mean particle size of FeONPs around 163.5 and polydispersity index 0.091 with a zeta potential of ?13.8 mV. Differential scanning colorimetry (DSC) exhibited an endothermic peak at 176.91°C. Vibrating sample magnetometer (VSM) analysis showed superparamagnetic properties of iron nanoparticles with a magnetization value of 3.483 emu/g and the results indicated superparamagnetic behavior of prepared iron nanoparticles at room temperature, thus highlighting their potential as magnetically targeted drug delivery system. This biosynthetic method has been proven to be cost-effective, environment friendly and promising for use in biomedical sciences.

Gene expression and apoptosis response in hepatocellular carcinoma cells induced by biocompatible polymer/magnetic nanoparticles containing 5-fluorouracil

BACKGROUND: Super-paramagnetic iron oxide nanoparticles (SPION) contain a chemotherapeutic drug and are regarded as a promising technique for improving targeted delivery into cancer cells. RESULTS: In this study, the fabrication of 5-fluorouracil (5-FU) was investigated with loaded Dextran (DEXSPION) using the co-precipitation technique and conjugated by folate (FA). These nanoparticles (NPs) were employed as carriers and anticancer compounds against liver cancer cells in vitro. Structural, magnetic, morphological characterization, size, and drug loading activities of the obtained FA-DEX-5-FUSPION NPs were checked using FTIR, VSM, FESEM, TEM, DLS, and zeta potential techniques. The cellular toxicity effect of FA-DEX-5-FU-SPION NPs was evaluated using the MTT test on liver cancer (SNU-423) and healthy cells (LO2). Furthermore, the apoptosis measurement and the expression levels of NF-1, Her-2/neu, c-Raf-1, and Wnt-1 genes were evaluated post-treatment using flow cytometry and RT-PCR, respectively. The obtained NPs were spherical with a suitable dispersity without noticeable aggregation. The size of the NPs, polydispersity, and zeta were 74 ± 13 nm, 0.080 and 45 mV, respectively. The results of the encapsulation efficiency of the nano-compound showed highly colloidal stability and proper drug maintenance. The results indicated that FA-DEX-5-FU-SPION demonstrated a sustained release profile of 5-FU in both phosphate and citrate buffer solutions separately, with higher cytotoxicity against SNU-423 cells than against other cells types. These findings suggest that FA-DEX-SPION NPs exert synergistic effects for targeting intracellular delivery of 5-FU, apoptosis induction, and gene expression stimulation. CONCLUSIONS: The findings proved that FA-DEX-5-FU-SPION presented remarkable antitumor properties; no adverse subsequences were revealed against normal cells.

Application status of superparamagnetic iron oxide in sentinel lymph node biopsy for breast cancer / 国际外科学杂志

The axillary lymph node status is the most important prognostic index of breast cancer, so the accurate assessment of axillary lymph node metastasis has always been a hot topic in breast cancer research. Today, sentinel lymph node biopsy (SLNB) has become the preferred surgical procedure for axillary lymph node negative early breast cancer. The selection of tracers is also a key link in the study of SLNB and lymphatic drainage area of breast cancer. Traditional tracers (blue dye, nuclide and fluorescent tracers, etc.) have many problems, such as allergy, poor localization specificity and radioactivity to human body, which limit their promotion and application in clinic. However, superparamagnetic iron oxide nanoparticle (SPION) can effectively improve these shortcomings and has the advantages that other tracers cannot replace. It can be an ideal tracer for SLNB of breast cancer and has a good application prospect. This article mainly describes the current application of SPION in SLNB of breast cancer, and outlines the advantages and disadvantages of this tracer.

Influencia de un campo magnético oscilante en columnas poliméricas con nanopartículas magnéticas / Influence of an oscillating magnetic field on polymeric columns with magnetic nanoparticles / Influência de um campo magnético oscilante em colunas poliméricas com nanopartículas magnéticas

Resumen Las nanopartículas magnéticas de magnetita (MNP) presentan comportamiento superparamagnético, lo que les confiere propiedades importantes como bajo campo coercitivo, fácil modificación superficial y niveles de magnetización aceptables. Esto las hace útiles en técnicas de separación. Sin embargo, pocos estudios han experimentado con las interacciones de las MNP con campos magnéticos. Por tanto, el objetivo de esta investigación fue estudiar la influencia de un campo magnético oscilante (CMO) en columnas monolíticas poliméricas con nanopartículas magnéticas vinilizadas (VMNP) para cromatografía líquida capilar (cLC). Para ello, se sintetizaron MNP mediante coprecipitación de sales de hierro. La preparación de las columnas monolíticas poliméricas se realizó por copolimerización y la agregación de VMNP. Aprovechando las propiedades magnéticas de las MNP, se estudió la influencia de los parámetros como frecuencia de resonancia, intensidad y tiempo de exposición de un CMO, aplicado a las columnas sintetizadas. Como resultado se obtuvo una mejor separación de la muestra según los parámetros medidos, de modo que se logró una resolución de la columna (Rs) de 1,35. Las propiedades morfológicas de las columnas fueron evaluadas mediante microscopía electrónica de barrido (SEM). Los resultados de las propiedades cromatográficas revelaron que la mejor separación de la muestra de alquilbencenos se da en condiciones de 5,5 kHz y 10 min de exposición en el CMO. Este estudio constituye una primera aplicación en técnicas de separación cromatográficas para futuras investigaciones en nanotecnología.

Abstract Magnetite magnetic nanoparticles (MNP) exhibit superparamagnetic behavior, which gives them important properties such as low coercive field, easy surface modification and acceptable levels of magnetization, making them useful in separation techniques. However, few studies have experimented the interactions they have with magnetic fields. For this reason, in this research, the influence of an oscillating magnetic field (CMO) on polymeric monolithic columns containing vinylized magnetite magnetic nanoparticles (VMNP) for capillary liquid chromatography was studied. For this, MNP were synthesized, by co-precipitation of iron salts. The preparation of the polymeric monolithic columns was carried out by the copolymerization method and the subsequent aggregation of VMNP. Taking advantage of the magnetic properties of the MNPs, the influence of various parameters (resonance frequency, intensity, and exposure time) of an CMO applied to the synthesized columns was studied. As a result, a better separation of the sample according to the measured parameters was obtained. Thus, achieving a column resolution (Rs) of 1.35. The morphological properties of monolithic columns were evaluated using scanning electron microscopy (SEM). The results of the chromatographic properties showed that the best separation of the sample of alkylbenzenes (ABS) in cLC occurs under conditions of 5.5 kHz and 10 min of exposure in the CMO. This study constitutes the first application in chromatographic separation techniques for future nanotechnology research.

Resumo As nanopartículas de magnetita magnética (MNPs) têm comportamento superparamagnético, o que lhes confere propriedades importantes como baixo campo coercitivo, fácil modificação da superfície e níveis aceitáveis de magnetização, tornando os úteis nas técnicas de separação. No entanto, poucos estudos foram realizados experimentando as interações exercidas pelos campos magnéticos. Portanto, o objetivo da presente investigação foi estudar a influência de um campo magnético oscilante (CMO) em colunas monolíticas poliméricas contendo nanopartículas magnéticas vinilizadas (VMNPs) para cromatografia líquida capilar (cLC). Para isso, MNPs foram sintetizados por co-precipitação de sais de ferro. A preparação das colunas monolíticas poliméricas foi realizada por copolimerização e subsequente agregação de VMNPs. Em seguida, aproveitando as propriedades magnéticas do MNPs, estudou-se a influência de vários parâmetros (frequência de ressonância, intensidade e tempo de exposição) de uma CMO aplicada nas colunas sintetizadas, obtendo vantagens como uma melhor separação da amostra e uma resolução (Rs) de coluna de 1,35. As propriedades morfológicas das colunas monolíticas foram avaliadas por microscopia eletrônica de varredura (SEM). Os resultados das propriedades cromatográficas mostraram que a melhor separação da amostra de alquilbenzenos (ABS) em cLC ocorre em condições de 5,5 kHz e 10 min de exposição na CMO. Este estudo constitui uma primeira aplicação em técnicas de separação cromatográfica para futuras investigações em nanotecnologia.

Effect of nanoparticles carrying chondroitin sulfate ABC on the migration of schwann cells in a magnetic field / 中国组织工程研究

BACKGROUND: The clinical effect of spinal cord injury is usually unfavorable due to the lack of axon regeneration and the formation of glial scar. Schwann cells, as the support cells for nerve regeneration, have poor migration ability in the central nervous system with abundant astrocytes, which limit its effect on axon regeneration. OBJECTIVE: To explore the effect on the migration of Schwann cells containing superparamagnetic nanoparticles loaded with chondroitinase ABC (ChABC) in the region of astrocytes in the external magnetic field. METHODS: Schwann cells and astrocytes were extracted from sciatic nerves and brachial plexus and cerebral cortex of Sprague-Dawley rats of postnatal day 1 to 3. Cell purity was identified by immunofluorescence staining. The toxicity of superparamagnetic nanoparticles (PEI-SPIONs) to Schwann cells was analyzed by live/dead cell staining. Schwann cells were transfected with PEI-SPIONS in an external magnetic field of 1.4Td for 2 days. The optimal transfection concentration of PEI-SPIONS used was 2 mg/L and the optimal mass ratio of PEI-SPIONS to ChABC was 1:4. Cell migration test was used to evaluate the migration ability of not-treated Schwann cells, PEI-SPIONs/ ChABC transfected Schwann cells, and PEI-SPIONs/ChABC transfected Schwann cells in an external magnetic field. RESULTS AND CONCLUSION: The purity of Schwann cells and astrocytes reached to (91.7±1.2)% and (93.3±2.2)%, respectively. Compared with the Schwann cells group, the number of PEI-SPIONs/ChABC-transfected Schwann cells that entered the region of astrocytes was significantly increased (P < 0.05). Under the external magnetic field, the number of PEI-SPIONs/ChABC-transfected Schwann cells that entered the region of astrocytes and the cell migration distance were significantly increased as compared with the Schwann cells group (P < 0.005). In summary, PEI-SPIONs/ChABC transfection can enhance the ability of Schwann cells to break the glial scar, and increase the fusion of astrocytes. Under the guidance of external magnetic field, the migration ability of Schwann cells is significantly elevated. This method may be a new strategy to promote nerve regeneration after spinal cord injury.

Endothelial progenitor cells in the peripheral blood of patients with moyamoya disease labeled with superparamagnetic iron oxide in vitro for MRI detection

Moyamoya disease (MMD) is currently thought to involve endothelial progenitor cells (EPCs). We investigated whether superparamagnetic iron oxide (SPIO) can be used to label EPCs. Mononuclear cells from 10 moyamoya disease patients were isolated, and cluster of differentiation 133 (CD133) positive cells sorted by magnetic-activated cell sorting were cultured in vitro. The positive rates of CD133, vascular endothelial growth factor receptor (VEGFR)-2, and cluster of differentiation 34 (CD34) were detected by flow cytometry. The cells were co-cultured with fluorescence labeled Dil-acetylated-low-density lipoprotein (Dil-ac-LDL) and Ulex europaeus agglutinin-1 (UEA-1) to observe the endocytosis of Dil-ac-LDL and binding to UEA-1. Prussian blue staining and transmission electron microscopy were used to observe the endocytosis of different SPIO concentrations in EPCs, and CCK-8 was used to detect proliferation of cells transfected with different concentrations of SPIO. T2 weighted imaging (T2WI) signals from magnetic resonance imaging after SPIO endocytosis were compared. Positive rates of CD133, VEGFR-2, and CD34 on sorted mononuclear cells were 68.2±3.8, 57.5±4.2, and 36.8±6.5%, respectively. The double-positive expression rate of CD34 and VEGFR-2 was 19.6±4.7%, and 83.1±10.4% of cells, which showed the uptake of Dil-ac-LDL and binding with UEA-1. The labeling efficiencies of SPIO at concentrations of 25 and 50 μg/mL were higher than for 12.5 μg/mL. The proliferation of cells was not influenced by SPIO concentrations of 12.5 and 25 μg/mL. After labeling, the T2WI of EPCs was reduced. The concentration of 25 μg/mL SPIO had high labeling efficiency detected by magnetic resonance imaging (MRI) without decreased EPCs viability.

In vitro study of GOD/Fe3O4 loaded PLGA nanoparticles in the treatment of retinoblastoma / 解放军医学杂志

Objective To evaluate the therapeutic potential of a novel type of Poly (lactic-co-glycolic acid) (PLGA) nanoparticles loaded with glucose oxidase (GOD)/superparamagnetic iron oxide nanoparticles (Fe3O4Nps) on retinoblastoma (RB) cells in vitro. Methods PLGA nanoparticles loaded with GOD/Fe3O4 (PFG) were prepared by double emulsification. Their particle size, potential, external morphology, and internal structure were examined. Particles that made of PLGA (control), PLGA loaded with GOD (PG), and PLGA loaded with Fe3O4 (PF) are served as control. Y79 cells that were incubated with different particles are termed control group, PF group, PG group, and PFG group. After co-incubation with nanoparticles, cell viability, and reactive oxygen species production were detected. Results PLGA nanoparticles loaded with GOD/Fe3O4 were successfully prepared. The form of PLGA nanoparticles was uniform and showed a round shape with a diameter of 299.3 nm. The nanoparticles were engulfed by Y79 cells after co-incubation with Y79 cells, producing a large number of reactive oxygen species. Cytotoxicity test results showed that the cell viability of Y79 cells in PLGA nanoparticle group coated with GOD/Fe3O4 [(53.648±2.565)%] was significantly lower than that in control group [(100.028±4.491)%], PF group [(97.782±17.520)%] or PG group [(87.438±3.537)%](F=21.226, P<0.01); The cell viability of Y79 cells in 0.25 μg/ml PFG nanoparticle group [(51.770±1.529)%] was significantly lower than that in control group [(100.000±5.021)%], 0.0625 μg/ml group [(85.723±6.903)%] and 0.125 μg/ml group [(74.535±8.282)%] (F=34.593, P<0.05). Massive cell death was detected in the PFG group under laser confocal microscope. Conclusions The novel type of PLGA nanoparticles loaded with GOD/Fe3O4 toxic to Y79 tumor cells with a good reactive oxygen generation ability. It provides a potential treatment for RB.

USPIO-enhanced MRI for lymph-node metastases from abdominal and pelvic malignancies: Meta-analysis / 中国医学影像技术

Objective To investigate value of ultrasmall superparamagnetic iron oxide (USPIO)-enhanced MRI in diagnosis of lymph node metastasis from abdominal and pelvic malignancies with Meta-analysis.Methods A systematic search was conducted in PubMed,Embase,Cochrane Library,Wanfang,VIP and CNKI databases.The literature were screened according to inclusion and exclusion criteria,and four tabular data were extracted.With Meta Disc version 1.4 and STATA 11.0 software,statistical analysis was performed and heterogeneity of the included articles was tested.Based on the result of heterogeneity test,proper effect model was selected to calculate the pooled sensitivity and specificity.Summary receiver operating characteristics curve was obtained,and the area under curve (AUC) was calculated.Results Totally 20 English literature were enrolled,including 1 211 patients and 3 583 lymph nodes.The pooled sensitivity and specificity for USPIO-enhanced MRI in diagnosis of lymph node metastasis was 0.89 (95％CI [0.86,0.91]) and 0.96 (95 ％CI [0.95,0.96]),and AUC was 0.98,respectively.Regression analysis revealed that the heterogeneity may result from the location of tumors,and subgroup analysis showed that pooled sensitivity in diagnosis of lymph node metastasis in abdominal malignancies was good.Conclusion USPIO-enhanced MRI has good diagnostic efficacy in diagnosis of lymph node metastasis from abdominal and pelvic malignancies.

Quantitative MRI of SD-rat adipose derived stem cells labeled with a new type paramagnetic nanoparticles in rats in vivo / 中国介入影像与治疗学

Objective To explore the feasibility of tracking migration and distribution of SD-rat adipose derived stem cells (ADSCs) labeled with Polyethylene Glycol/Polyehthyleneimine modified superparamagnetic iron oxide (PEG/PEI-SPIO) in rats with chronic cerebral ischemia using MRI.Methods Thirty female SD rats underwent permanent occlusion of bilateral common carotid arteries 6 months were divided into PEG/PEI-SPIO labeled group and unlabeled group (each n =15).Labeled or unlabeled ADSCs suspension was injected into the right ventricle of rats in two groups,respectively.MR scans were performed at the 7th,14th and 21st day after transplantation for each 5 rats.T2 value of T2mapping sequence in hippocampus,cortex and cerebellum were measured.Then the rats were scarified,and the brains were obtained,and Prussia dyeing was performed.Under high magnification,blue dye cells at each time points and brain area were counted.T2 values and blue dye cells were statistically analyzed.Results Class round hypointensity areas were detected in temporol-parietal cortex and hippocampus in both groups on T2WI,T2* WI and SWI.T2 value of the right temporolparietal cortex and hippocampus in the labeled group was shorter than those of the unlabeled group on the 14th day after transplantation (P=0.013,0.045).T2 value of the right temporol-parietal cortex in the labeled group was shorter than that of the unlabeled group on the 21st day after transplantation (P=0.007).The number of blue dye cell of the right temporol-parietal cortex on the 14th and 21th day,hippocampus on the 14th day in the labeled group were more than those of the unlabeled group after transplantation (P=0.029,0.032,0.043).Conclusion ADSCs labeled with PEG/PEI-SPIO transplanted into lateral ventricle of SD rat could migrate to the damaged areas caused by chronic cerebral ischemia.It is possible to use quantitative MRI to track migration and distribution of ADSCs labeled with PEG/PEI-SPIO in rat brain.

Carbon dioxide/methanol conversion cycle based on cascade enzymatic reactions supported on superparamagnetic nanoparticles

ABSTRACT The conversion of carbon dioxide into important industrial feedstock is a subject of growing interest in modern society. A possible way to achieve this goal is by carrying out the CO2/methanol cascade reaction, allowing the recycle of CO2 using either chemical catalysts or enzymes. Efficient and selective reactions can be performed by enzymes; however, due to their low stability, immobilization protocols are required to improve their performance. The cascade reaction to reduce carbon dioxide into methanol has been explored by the authors, using, sequentially, alcohol dehydrogenase (ADH), formaldehyde dehydrogenase (FalDH), and formate dehydrogenase (FDH), powered by NAD+/NADH and glutamate dehydrogenase (GDH) as the co-enzyme regenerating system. All the enzymes have been immobilized on functionalized magnetite nanoparticles, and their reactions investigated separately in order to establish the best performance conditions. Although the stepwise scheme led to only 2.3% yield of methanol per NADH; in a batch system under CO2 pressure, the combination of the four immobilized enzymes increased the methanol yield by 64 fold. The studies indicated a successful regeneration of NADH in situ, envisaging a real possibility of using immobilized enzymes to perform the cascade CO2-methanol reaction.

Ecotoxicidad de nanopartículas metálicas y superparamagnéticas de óxido de hierro en dos especies / Ecotoxicity of metalic and superparamagnetics iron oxide nanoparticles in two species

Introducción: la nanotecnología y el empleo de materiales a nano escala son un área relativamente nueva de la ciencia y la tecnología con un gran crecimiento en el mercado global. Muchos de los productos no cuentan con estudios que garanticen su uso seguro, tanto para el hombre como para los ecosistemas. Los estudios ecotoxicológicos permiten evaluar los efectos de un determinado xenobiótico sobre especies representativas de los diferentes compartimentos ambientales. Objetivo: evaluar los efectos tóxicos de nanopartículas de Ag, Au, Ag/Ag y superparamagnéticas de óxido de hierro, en dos especies bioindicadoras de los ecosistemas terrestre y acuático. Métodos: como parte de los estudios de seguridad se realizaron ensayos de toxicidad aguda por contacto en lombriz de tierra de la especie Eisenia andrei, con una duración de 96 horas y estudios en anfibios de la especie Osteopillus septentrionales en diferentes etapas del desarrollo (embrionario y larval). Se evaluó la ocurrencia de mortalidad y de efectos tóxicos, en el caso del ensayo en lombriz de tierra; se determinó además la viabilidad celular. Resultados: los efectos tóxicos más significativos en el caso de la lombriz de tierra fueron, la ocurrencia de alteraciones fisiológicas y conductuales al ser expuesta a NPs de Ag de 3 nm y superparamagnéticas de óxido de hierro, estas últimas provocaron citotoxicidad a la concentración 1,38 mg/mL. En el caso de los anfibios se evidenció toxicidad en NPs de Ag 3 nm y superparamagnéticas de óxido de hierro. Conclusiones: todas las nanopartículas mostraron efectos tóxicos en las especies bioindicadoras evaluadas(AU)

Introduction: Nanotechnology and the use of nanoscale materials are a relatively new area of science and technology with big growth in the global market. Many of these products don't have studies that guarantee their safe use, both for man and for ecosystems. Ecotoxicological studies allow the evaluation of the effects of a particular xenobiotic on representative species of the different environmental compartments. Objective: To evaluate the toxic effects of nanoparticles of Ag, Au, Ag / Ag and super paramagnetic iron oxide in two bioindicators of terrestrial and aquatic ecosystems. Methods: Acute contact toxicity tests were carried out on ground worm of the Eisenia andrei species, with a duration of 96 hours and studies on amphibians of the species Osteopillus septentrionales at different stages of development (embryonic and larval). The occurrence of mortality and toxic effects was evaluated in the case of earthworm test; cell viability was also determined. Results: The most significant toxic effects in the case of earthworms were the occurrence of physiological and behavioral alterations when exposed to 3 nm Ag of superparamagnetic iron oxide nanoparticles, where the latter caused cytotoxicity at concentration of 1.38 mg / mL. In the case of amphibians, toxicity was evidenced in Ag 3 nm nanoparticles and superparamagnetic iron oxide. Conclusions: All nanoparticles showed toxic effects in the evaluated bioindicator species(AU)

Experimental study of superparamagentic scaffolds used to repair rabbit mandibular defect / 医学研究生学报

Objective Sperparamagnetic material is widely used in tumor localization and treatment , but there are still few studies in bone tissue engineering .This study aims to investigate the osteogenic efficiency of superparamagnetic scaffolds poly lactic acid hydroxy acetic acid (PLGA)/iron-doped hydroxyapatite (Fe-HA) for repairing rabbit mandibular defects , as well as evaluating the biocompatibility of the material . Methods 36 New Zealand rabbits were randomly selected and randomly divided into 6 groups, control without and with static magnetic field ( SMF ) groups ( no material is implanted), PLGA scaffold without and with SMF groups (implanted PLGA), PLGA/Fe-HA scaffold without and with SMF groups ( im-planted PLGA/Fe-HA), each group has 6 rabbits.We created bilat-eral mandibular defect models , executed the rabbits at 4 weeks and 12 weeks post-surgery, marked the mandibular specimens which detected by general observation, Micro-CT and HE staining, and ana-lyzed the results of bone mineral density in defect area .The hematological detection , pathological examination of liver and kidney sam-ples were carried out at 12 weeks pot-surgery.. Results The PLGA/Fe-HA scaffold without and with SMF groups began to appear rough defect area edge , decreased defect diameter , new bone formation from 4 weeks; the defect area formed a smooth , continuous bone repair from 12 weeks.The PLGA scaffold without and with SMF groups appeared rough , irregular callus repair , visible boundary between defect edge and normal bone tissue .There are still have part of unrepaired bone defect in the center of defect area in the control without and with SMF groups.At 12 weeks , the bone mineral density of PLGA/Fe-HA scaffold with SMF group [(572.50±19.09) mgHA/cm3] , respectively, compared with the PLGA scaffold with SMF group [(467.00±6.24)mgHA/cm3], the control with SMF scaffold group [(480.00±2.08) mgHA/cm3], the PLGA/Fe-HA scaffold without SMF group [(461.00±19.79)mgHA/cm3], the PL-GA scaffold without SMF group [(446.00±11.31)mgHA/cm3] and the control without SMF group [(422.00±28.28) mgHA/cm3], all the differences were statistically significant ( P<0.05).The bone mineral density of PLGA/Fe-HA scaffold with SMF group at 4 weeks [(572.50±19.09)mgHA/cm3] was significantly higher than that at 12 weeks [(276.00±28.28)mgHA/cm3] (P<0.05), the differences between 4 weeks and 12 weeks in other groups were statistically significant (P<0.05). Conclusion The superparama-gentic PLGA/Fe-HA scaffolds can promote the repair of bone defect , optimize the osteogenic effect of the material with SMF .Also ,the scaffold showed a good biocompatibility .

Hypoxia Enhances the Therapeutic Potential of Superparamagnetic Iron Oxide-labeled Adipose-derived Stem Cells for Myocardial Infarction / 华中科技大学学报（医学）（英德文版）

Adipose-derived stem cells (ASCs) induce therapeutic angiogenesis due to pro-angiogenic cytokines secretion.Superparamagnetic iron oxide (SPIO) nanoparticles are critical for magnetic resonance (MR) tracking of implanted cells.Hypoxia is a powerful stimulus for angiogenic activity of ASCs.In this study,we investigated whether therapeutic potency could be enhanced by implantation of hypoxia-preconditioned SPIO-labeled ASCs (SPIOASCs) into the infarcted myocardium.ASCs and SPIOASCs were cultured under 2％ O2 (hypoxia) or 95％ air (normoxia).Cells were intramyocardially injected into the infarcted myocardium after 48-h culture.We found that hypoxia culture increased the mRNA expression of hypoxia-inducible factor-1 alpha (HIF-lαt) and vascular endothelial growth factor (VEGF) in ASCs and SPIOASCs.The VEGF protein in the conditioned medium was significantly higher in hypoxic ASCs and SPIOASCs than in normoxic ASCs and SPIOASCs.The capillary density and left ventricular contractile function in the infarcted myocardium were significantly higher 4 weeks after implantation with hypoxic ASCs and SPIOASCs than with normoxic ASCs and SPIOASCs.Improvement in the capillary density and left ventricle function didn't differ between hypoxic ASCs-transplanted rats and hypoxic SPIOASCs-transplanted rats.Hypoxic culture enhanced the angiogenic efficiency of ASCs.It was concluded that implantation of hypoxic ASCs or SPIOASCs promotes therapeutic angiogenesis and cardiac function recovery in the infarcted myocardium.SPIO labeling does not impact the beneficial effect of hypoxic ASCs.

Superparamagnetic iron oxide nanoparticle targeting of adipose tissue-derived stem cells in diabetes-associated erectile dysfunction / 亚洲男科学杂志(英文版)

Erectile dysfunction (ED) is a major complication of diabetes, and many diabetic men with ED are refractory to common ED therapies. Adipose tissue-derived stem cells (ADSCs) have been shown to improve erectile function in diabetic animal models. However, inadequate cell homing to damaged sites has limited their efficacy. Therefore, we explored the effect of ADSCs labeled with superparamagnetic iron oxide nanoparticles (SPIONs) on improving the erectile function of streptozotocin-induced diabetic rats with an external magnetic field. We found that SPIONs effectively incorporated into ADSCs and did not exert any negative effects on stem cell properties. Magnetic targeting of ADSCs contributed to long-term cell retention in the corpus cavernosum and improved the erectile function of diabetic rats compared with ADSC injection alone. In addition, the paracrine effect of ADSCs appeared to play the major role in functional and structural recovery. Accordingly, magnetic field-guided ADSC therapy is an effective approach for diabetes-associated ED therapy.

Transhepatic arterial embolization with superparamagnetic iron oxide and lipiodol for the treatment of VX2 tumor in rabbits / 中南大学学报(医学版)

Objective:To evaluate the feasibility and therapeutic efficacy of transhepatic arterial embolization with superparamagnetic iron oxide (SPIO) and lipiodol (LIP) for the treatment of VX2 tumor in rabbits.Methods:Twenty-four rabbits with hepatic VX2 tumors by surgical implantation were randomly divided into 4 groups and treated with transhepatic arterial embolization of 4 different agents as follows (n=6 each):doxorubicin (DOX) group,DOX-LIP group,SPIO-DOX group,and SPIO-DOX-LIP group.Liver function (AST and ALT) was measured at 0,1,3,5 and 7 d after transhepatic arterial embolization.The serum DOX level was measured at 0,5,15,30,60,and 120 minutes after transhepatic arterial embolization.MRI was performed at 7 d after the treatment to assess the distribution of SPIO in the SPIO-DOX group and SPIO-DOX-LIP group,while CT was performed to assess the distribution of LIP in the DOX-LIP group and SPIO-DOX-LIP group.All the rabbits were sacrificed and their livers were removed at 7 d after treatment for the detection of tissue DOX level.The histopathologic examinations were performed including HE staining,Prussian blue staining and TUNEL assay,and then the tumor necrosis percentage and apoptosis index were calculated.Results:Compared to the DOX group,the levels of AST and ALT in other 3 groups were significantly elevated at 1 and 3 d after embolization (P＜0.05).The levels of ALT and AST in the DOX group,DOX-LIP group or SPIO-DOX-LIP group returned to the baseline at day 7,there were no significant differences (P＞0.05).The SPIO-DOX-LIP group exhibited the lowest serum DOX level at all time points up to 120 minutes after embolization (P＜0.05).However,the tissue DOX level in the SPIO-DOX-LIP group was the highest among all groups at day 7 (P＜0.05).The SPIO-DOX group and SPIO-DOX-LIP group showed significantly lower MRI signal intensity of tumors in T2 weighted imaging (T2WI) at day 7.Meanwhile DOX-LIP group and SPIO-DOX-LIP group showed that high-density lipiodol was deposited in the tumors in CT images.Histopathologic findings showed an almost complete central necrosis coagulation of tumors in the SPIO-DOX-LIP group,and the tumor necrosis percentage and tumor apoptosis index were significantly increased in the SPIO-DOX-LIP group compared to those in other 3 groups (P＜0.05).Conclusion:This novel drug-delivery system of SPIO nano-drug carrier together with LIP is safe and feasible when it is used for transhepatic arterial embolization for liver tumor.It provides an excellent MR and CT visualization and improves the therapeutic efficacy for the treatment of rabbit VX2 liver tumor.

Preparation of anti-EGFR-PEG-SPIO molecular probe and its targeting MRI for lung adenocarcinoma cells / 中国医学影像技术

Objective To observe the targeting function of high affinity anti-EGFR monoclonal antibody (Cetuximab)conjugated superparamagnetic iron oxide-dopamine (anti-EGFR-PEG-SPIO) lung cancer cells via epidermal growth factor receptor (EGFR),as well as the feasibility for surveillance of tumor targeting with MRI.Methods Nanoparticles (NPs)of anti-EGFR-PEG-SPIO and PEG-SPIO were prepared,and the morphology of nanoparticles was observed with transmission electron microscope (TEM).The hydrodynamic diameter and R2 values of nanoparticles before and after conjugation with anti-EGFR were performed with dynamic light scattering (DLS) and MRI.MRI was performed in incubation with anti-EGFR-PEG-SPIO and PEG-SPIO after 2 h in vitro.The cellular uptake of anti-EGFR-PEG-SPIO and PEG-SPIO was further evaluated using Prussian blue staining and TEM.Results Anti-EGFR-PEG-SPIO and PEG-SPIO showed signal intensity of H460 cells on T2WI,decreased significantly compared with PEG-SPIO.The rate of signal intensity change was -58.2％,-82.7％,-94.4％ and-98.3％,respectively,at iron concentrations of (0,10,20,40,80 μg/ml) of antiEGFR-PEG-SPIO.Prussian blue staining and TEM showed that a lot of intracellular irons of anti-EGFR-PEG-SPIO were observed in H460 cells,but few of PEG-SPIO.Conclusion The effect of active targeting via anti-EGFR in EGFR overexpressed cells can be achieved with anti-EGFR-PEG-SPIO in H460 cells in vitro,and the targeting delivery process could be monitored with 3.0T MRI.

Research progresses of superparamagnetic iron oxide nanoparticles in precision medicine / 中国医学影像技术

The demand for diagnosis and therapy of diseases should be higher in the era of precision medicine.The superparamagnetic iron oxide nanoparticles (SPION) is used in diagnosis,therapy,and monitor of diseases due to its good superparamagnetism,which has always been paid more attention in molecular imaging.The research progresses of SPION in precision medicine were reviewed in this article.

MR molecular imaging of pancreatic cancer cell targeted by superparamagnetic iron oxide nanoparticles / 中国医学影像技术

Objective To explore the feasibility of MR molecular imaging in human pancreatic cancer cell (BxPC-3 cell) targeted by superparamagnetic iron oxide nanoparticles (SPION).Methods Both MUC1 SPION probes with MUC1 targeted modification (targeted group) and bull serum albumin (BSA)-SPION as the control (non targeted group) were prepared.The cytotoxicity of MUC1 SPION in different concentrations (0,6.25,12.50,25,50,100,200 μg/ml) was verified by MTT (3 [4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay.BxPC-3 cells were cultured with MUC1-SPION (targeting group) and BSA-SPION (control group) in different concentration as 50,100,200 μg/ml,respectively for 2 h.Then MRI scans were performed,the transverse relaxation time (T2) value and the enhancement ratio of T2 were recorded and calculated.The combination conditions of targeting probes and cells were observed by prussian blue staining.Results The cell cytotoxicity of MUC1 SPION in different concentrations showed no statistical difference according to MTT assay (F=1.74,P 0.18).There were statistical differences of the T2 value and the enhancement ratio of T2 for the concentration as 50,100,200 μg/ml,respectively (all P＜0.05).More blue particles were observed by prussian blue staining in targeted group than in non targeted group.Conclusion MUC1-SPION has favourable targeting ability to BxPC 3 cell,and MRI of BxPC-3 cell targeted by SPION is satisfied security and feasibility.

MR molecular probes RGD-USPIO in evaluation effect of ucleoside combination on human hepatoma cell line Bel-7402 in vitro / 中国医学影像技术

Objective To evaluate the effect and the anti-tumor mechanism of nucleoside combination on human hepatoma cell line Bel-7402 with Arg-Gly-Asp sequence labeled by ultrasmall superparamagnetic iron oxide (RGD-USPIO).Methods The tumor cells Bel-7402 of logarithmic phlyhase were divided into experimental group and control group,treated with 1 mmol/L nucleoside combination and 1640 medium respectively.The two group were co-cultured for 48 h,and were added RGD-USPIO and co-cultured for 6 h.Then the two groups were proceeded with MR scanning,and the signal intensity of T2WI were measured.After extraction of the total RNA and protein of experiment group and control group,the expression of integrin avβ3 was detected using real-time PCR and Western blot.Results The T2WI signal intensity of experimental group (997.35±42.83) was higher than that of control group (241.05±15.36,t 28.79,P＜0.01).Compared with control group,the expression of integrin αvβ3 mRNA in experimental group was (0.22±0.02) times (t=4.50,P＜0.01).According to Western blot,the protein bands of experimental group were relatively lighter than that of control group,the expression of integrin αvβ3 in experimental group was lower (t =11.88,P＜0.01).Conclusion Nucleoside combination has anti-tumor effect by inhibiting integrin ligand-receptor binding,and the anti tumor mechanism may be related to the induction of tumor cell apoptosis.MR molecular probes can conveniently and accurately evaluate the anti-tumor effect of nucleoside combination on Bel-7402 cells.

Magnetic resonance imaging of nude mice model injected in USPIO-PEG-sLeX in vivo / 实用放射学杂志

Objective To explore the value of the molecular probe USPIO-PEG-sLeX on nasopharyngeal carcinoma xenograft in nude mice.Methods The USPIO nanoparticles was synthesized by physical deposition method,and which was modified by PEG to synthesize USPIO-PEG-sLeX .The nude mice of nasopharyngeal carcinoma xenograft were divided into experimental and control groups.USPIO-PEG-sLeX and USPIO-PEG were injected into nude mice of experimental and control groups by caudal vein,respectively.MR T2 mapping imaging was scanned before and after the injection,and analyzed the changes of T2 values between experimental and control groups. Results USPIO-PEG-sLeX had a good representation.The non-enhanced T2 values between control and experimental group had no statistical significance (P >0.05).However,T2 values of the mice in two groups before and after injections were statistically significant (P <0.05);and T2 values of experimental group were much lower than that of the control group after the injection,additionally,the difference of enhanced rate between the two groups was statistically significant (P <0.05).Conclusion USPIO-PEG-sLeX magnetic nanoparticles is potential to be a targeted contrast agent to ELAM-1 expression of nasopharyngeal carcinoma,and can be valuable in non-invasive dynamic monitoring the expression of ELAM-1.