approach for reducing the total cost of electricity generation [5-7]. It is well established that the use of suitable catalyst at the electrode of SOFC is the key issue for achieving the good SOFC cogeneration performance. Recently, several types of catalyst for OCM reaction have been studied and reported, from which the suitable catalysts for this reaction include SrF 2 /Nd 2 O3 , Mn/Na 2 WO 4 /SiO 2 , La 2 O3 , LaAlO 3 ,
Elemental analysis was performed using scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDS, EDAX 9100; EDAX International, Prairie View, IL). X-ray diffraction data were collected using an XD-D1 x-ray diffractometer (Shimadzu, Kyoto, Japan) with Cu-K α radiation ( λ = 0.154 nm) at 40 kV and 30 mA. Transmission electron microscopy (TEM, model JSM- 6360LV; JEOL, Tokyo, Japan) was operated at 200 kV to observe the morphology and sizes of the particle samples. A Thermo Noran Vantage (Thermo Scientific, Waltham, MA) energy-dispersive spectrometer was used. Temperatures were measured with a digital thermometer (TM902C, Shenzhen Jingtengwei Industrial Co, Ltd, Shenzhen, China). A high-frequency magnetic induction heating device (SPG- 06A, 230 kHz frequency, 5 to 30 A output alternating heating current) was provided by Shenzhen Shuangping High- Frequency Heater Factory (Shenzhen, China).
All animals were kept in stress-free, hygienic, and animal- friendly conditions (relative humidity 60% ± 10%, room tem- perature 20 ° C ± 2 ° C, and 12-hour light/dark cycle). Food and water were available ad libitum. All animal-study protocols were approved by the Ningbo University Institutional Animal Care and Use Committee (AEWC-2016–151), and experi- ments followed the Chinese “Regulation on the management of laboratory animals”, adopted in 1988. Healthy male rats (12 weeks old) were selected and randomly divided into one control group and six experimental groups (5, 15, and 30 mg/kg Fe 3O 4 -TiO 2 NPs or TiO 2 NPs, respectively) with six rats in each group. The observation period was 30 days. A staged approach to dosing method was used for selection of the dose ranges. When determining chemical dosage, care was taken to prevent any severe toxicity in the animal that could affect absorption, metabolism, distribution, or excretion. 22 Following this principle, the highest treatment
Briefly, a protective agent was added in two stages fol- lowed by chemical co-precipitation. The aqueous solutions containing 2 M Fe(II) and 1 M Fe(III) were prepared by dissolving FeCl 2 and FeCl 3 , respectively. To produce Fe 3O 4 NPs, 1 mL Fe(II) and 4 mL Fe(III) aqueous solutions were mixed at room temperature, followed by the addition of 0.5 g organic acid as adherent. Afterward, 0.5 M NaOH was dropwise added into the mixed solution to adjust the pH. The reaction was finished when the pH of the solution reached 11. The precipitates were then collected by a magnet and washed with 50 mL of deionized water three times, followed by addition of another 3 g of organic acid to achieve com- plete coating of the particle surface with the − NH 3 + group.
Nanotechnology offers an efficient alternative for cancer diagnostics and tumor target treatment due to the unique properties of nanostructures, such as large surface-to-volume ratio, porous structure, embedded effect, and size effect, which have been recognized as offering potential promising applications in biomedical engineering. Much effort has been extended to the development of novel nanocomposites and biomaterials for DNA detection, 1 intracellular labeling, 2 drug carrier, 3 cancer targeting, 4 imaging, 5 and so on.
phase were cultured in 96-well flat-bottomed plates in a triplicate pattern and treated with different concentrations of ART, MNPs-Fe 3O 4 , or the copolymer of ART with MNPs- Fe 3O 4 in the presence or absence of 40 µ M Z-VAD-FMK for 48 hours. MTT (20 µ L, 5 mg/mL) was added to each well and incubated for 4 hours. Then, 200 µ L of dimethylsulfox- ide was added to each well and the plate was vortexed for 10 minutes at 37 ° C. Finally, the optical density value (A) of each well was measured at a measurement wavelength of 540 nm using a plate reader (Model 550, BIO-RAD, Japan). Cell growth inhibition ratio was calculated as (1 − A 540 of experimental well/A 540 of blank control well) × 100%. Each assay was repeated at least 3 times.
different pH levels which are similar to the pH of the stomach and the pH of the blood. Generally, the pH of the stomach varies from 1–2 to 4–5. After eating, the stomach releases proteases and hydrochloric acid to aid digestion. In itself, the acid does not aid digestion, but the proteases that cleave proteins work best in an acidic environment. Therefore, after a high-protein meal, the stomach pH may drop to as low as 1–2. However, buffer quickly raises the pH back to 3–4. After the meal has been digested, the pH of stomach returns to a resting level of about 4–5. Before food arrives, the pH of the stomach is normally 5.0–6.0. It is clear that an ideal level of pH in the blood is about 7.4, and even changing this level slightly may have fatal consequences. Therefore, release of gallic acid from nanoparticles was determined using a 0.0001 M aqueous solution of Na 2 CO 3 32 and Na
Eight SD rats were used for the in vivo toxicity study. These rats were raised in stainless cages in ventilated animal rooms with a typical environment (23 ° C ± 1 ° C, 55% ± 15% humidity, and 12 h light/dark cycle) and had free access to water and food. After acclimatization to the environ- ment, the rats were separated into two groups (n = 4). Then, Fe 3O 4 -PLGA or Fe 3O 4 -PLGA-cRGD NPs at a final dosage of 1 mg lyophilized powder dissolving 1 mL phosphate- buffered saline (PBS) was administered to the rats by tail vein injection. Body weights were recorded every morn- ing, and overall animal health was determined by careful observations for signs of irritation, pain, discomfort, and inflammation.
does not apply to the controlled and proper administration of medical ozone. 12 Ozone therapy is based on high doses in order to stimulate the immunology system. Numerous studies have proven that ozone therapy effects are consis- tent and the therapy is safe and does not cause side effects. The ozone therapy mechanism of action is based on the formation of reactive oxygen species (ROS) and lipids oxidation products (LOP). Fortunately, ROS disappear quickly, as they are short-term acting particles. LOPs are distributed throughout the tissues; therefore, only a few molecules can act on the organs. Therefore instead of causing harm, these particles stimulate antioxidant defense, as well as modify the immune system.
After intragastric administration, 0.2–0.5 mL of blood from one mouse in each group were collected into an ethylene- diaminetetraacetic acid tube by enucleating eyeballs at the time points of zero minutes, hours 1, 3, 5, 6, and 7, and days 1, 3, 5, 7, and 10. The mice were then sacrificed by cervi- cal dislocation, and samples of heart, liver, spleen, lungs, kidneys, bone marrow, brain, stomach, and small intestine were collected. After removing the fatty and connective tissue on the joint, the remaining tissues were washed with physiologic saline, dried with filter paper, and weighed to determine Fe 3O 4 MNP content.
Abstract: While the potential impact of magnetic nanoparticles (MNPs) has been widely explored in almost all medical fields, including cardiology, one question remains; that is whether MNPs interfere with cardiac physiological processes such as the expression and function of ion channels, especially in vivo. KCNQ 1 channels are richly expressed in cardiac myocytes and are critical to the repolarization of cardiac myocytes. In this study, we evaluated the effects of Fe 3O 4 -magnetic nanoparticles (MNPs-Fe 3O 4 ) on the expression of KCNQ 1 in cardiac muscle of mice at rest and at different times following a single bout of swimming (SBS). Firstly, we demonstrated that the expression levels of KCNQ 1 channels are significantly up-regulated in mice following a SBS by means of reverse transcription polymerase chain reaction (RT-PCR) and western-blot. After treating mice with normal saline or pure MNPs-Fe 3O 4 separately, we studied the potential effect of MNPs-Fe 3O 4 on the expression profile of KCNQ 1 in mouse cardiac muscle following a SBS. A SBS increased the transcription of KCNQ 1 at 3 hours post exercise (3PE) 164% ± 24% and at 12 hours post exercise (12PE) by 159% ± 23% (P 0.05), and up-regulated KCNQ 1 protein 161% ± 27% at 12PE (P 0.05) in saline mice. In MNPs-Fe 3O 4
Forty ICR mice, half male and half female, were individually and randomly divided into four groups: control group (0.5 mL of sterile physiologic saline), low-dose group (300 mg/kg Fe 3O 4 - MNPs), medium-dose group (600 mg/kg Fe 3O 4 -MNPs), and high-dose group (1200 mg/kg Fe 3O 4 -MNPs). The mice in the exposed group were given different concentrations of Fe 3O 4 - MNPs, and those in the control group were given RPMI-1640 (Gibco Chemical Co, Carlsbad, CA) medium by single gastric perfusion and observed for the poisoning symptoms after administration of the drug; finally, they were all sacrificed under Avertin anesthesia by cervical dislocation after 14 days and
The procedure followed to prepare the proposed immunosen- sor is schematized in Figure 1C. The GCE was polished with 0.3 µ m and 0.05 µ m alumina, followed by successive sonica- tion in distilled water and ethanol for 5 minutes and dried in air. A porous nanostructure gold film was then deposited at a voltage of − 0.5 V for 50 seconds on the clean GCE that was immersed in 5 mL 0.08 M HAuCl 4 solution containing 0.004 M lead acetate. After thorough washing with water, the electrode was immediately followed by incubation with 20 µ L 0.5 mg/mL Ab 1 for one hour. After washing with 0.05% Tween-20 and phosphate-buffered solution, Ab 1 /Au/GCE was incubated in 3% bovine serum albumin and phosphate-buffered solution at 37 ° C for one hour to block excess active groups and nonspecific binding sites on the surface. The electrode was then washed with 0.05% Tween-20 and phosphate-buffered solution before use.
minor modifications. An aqueous solution of doxorubicin 5 mg/5 mL was emulsified in 10 mL dichloromethane, in which 120 mg of the copolymer and 4 mg magnetic nanopar- ticles had been dissolved, using a probe homogenizer or soni- cation at 20,000 rpm for 30 seconds. This w/o emulsion was transferred to a 50 mL aqueous solution of polyvinyl alcohol 1% and the mixture was probe-homogenized (or sonicated) at 72,000 rpm for one minute. The w/o/w emulsion formed was gently stirred at room temperature until evaporation of the organic phase was completed or the organic phase was evaporated (Heidolph Instruments). The nanoparticles were purified by applying two cycles of centrifugation (12,000 rpm for 1 hour in a Biofuge 28 RS, Heraeus centrifuge) and reconstituted with deionized and distilled water. The nanopar- ticles were finally filtered through a 1.2 mm filter (Millipore, Bedford, MA). In order to increase doxorubicin entrapment in the nanoparticles, the external aqueous phase used during the
Transparent glass-ceramics are attractive materials as optical advices because they have both the good formability of glasses and excellent optical properties of crystals. The size of crystals in transparent glass- ceramics must be smaller than the wavelength of visible light to reduce the scattering of light at the interface of crystals. For this purpose, glasses showing volume crystallization are desired because the growth of crystals is hindered by the other crystals around them so that the size of crystals can be controlled by the number density of nuclei. In addition, some nucleating agents (such as TiO 2 , ZrO 2 , P 2 O5 ,
DMP was suspended in 10 mL phosphate-buffered saline (PBS) solution, and incubated with 5 mg EDC and 5 mg NHS for 30 minutes at room temperature. Then, the products were separated using magnetic separation and centrifugation. After washing once in PBS, the residual solution was mixed with 5 mg PLGA, then intermittently sonicated for 30 minutes at room temperature. The products were then magnetically sepa- rated, and washed three times. The residual solution was mixed with 5 mg EDC, 5 mg NHS, and 500 µ L DOX (2 mg/mL). After intermittent sonication for 3 hours, the products were washed several times, until the supernatant solution became colorless. Then, 20 µ L of hydrazine hydrate solution was added, and the mixture was incubated under impulse sonication for 10 minutes at room temperature. After being washed with PBS, 200 µ L of transferrin solution (4 mg/mL), containing 5 mg EDC and 5 mg NHS, was added, and reacted under impulse sonication for 2 hours. The products were magnetically collected, then washed several times. TfDMP products were finally obtained by freeze- drying. Evaluation of DOX content proceeded by measuring the visual ultraviolet light absorbance of TfDMP at 479 nm, in a 1:2 mixture of hydrochloric acid and ethanol solution, as has been described in the literature previously. 27 The drug loading
To further study the biodistribution and excretion of our Gd-NPs, we performed ICP-MS on representative organs and tumor tissues (15 µ mol/kg) (Figure 3B). The concentrations of Gd in the heart, brain, spleen, lung, liver, kidney, and xenografted tumor were measured at 4, 12, and 24 hours after intravenous injection. The data indicated that the nanoprobes gradually accumulated in the spleen, lung, liver, and tumor tissue, whereas little Gd was found in the heart, brain, and kidney. The concentrations in the spleen and liver were 10.5-fold higher than in the kidney at 4 hours post-injection. Moreover, in the brain and lung there was a decrease, while in other organs there was a slight increase. Biodistribution is related to the characteristics of materials and the organ specificity. 35,36 Different nanomaterials have
After treatment with hyperthermia for different periods of time, the temperature change at the tumor site was deter- mined and is shown in Table 1. It can be seen that the tumor temperature in the mice treated with Fe 3O 4 -MNP increased to 41.71 ° C ± 1.52 ° C and in those treated with Fe 3O 4 -MNP- DNR-5-BrTet the temperature increased to 41.56 ° C ± 1.8 ° C after 20 minutes of hyperthermia. The tumor temperature was higher in these two groups than in the other groups, but there were no significant difference between them. Furthermore, no obvious change in temperature was observed in the mice not treated with Fe 3O 4 -MNP throughout the study. Interestingly, except for the increased temperature at the tumor site, the mice treated with Fe 3O 4 -MNP or Fe 3O 4 -MNP-DNR-5-BrTet did not show any increase in temperature elsewhere. These results show that Fe 3O 4 -MNP played an important role in the temperature changes at the tumor site in response to both extreme and moderate hyperthermia.
were incubated with MgNPs-Fe 3O 4 (1 µ g/mL, 10 µ g/mL, or 100 µ g/mL) for 24 hours in the absence or presence of N-acetylcysteine (NAC; 10 mM) (Sigma-Aldrich Co); NAC was added 3 hours before treatment with MgNPs-Fe 3O 4 . A stock solution of CM-H2DCFDA (5 mM) was freshly prepared in DMSO and diluted to a final concentration of 1 µ M in PBS. Cells were washed with PBS followed by incubation with 50 µ L of working solution of fluorochrome marker CM-H2 DCFDA for 30 minutes. Fluorescent imaging was recorded using an IX2 N-FL-1 microscope (Olympus Corporation, Tokyo, Japan), and analyzed using imaging software (Adobe Photoshop Elements 8; Adobe Systems Incorporated, San Jose, CA, USA). As a positive control, cells were treated with H 2 O 2 (100 µ M) for 24 hours.
Reagents used in cell culture include albumin solution from bovine serum (Sigma-Aldrich Co.), ascorbic acid (C 6 H 8 O 6 ; Sigma-Aldrich Co.), Dulbecco’s Modified Eagle’s Medium (DMEM; high glucose with l -glutamine and pyridoxine hydrochloride; GibcoÒ; Thermo Fisher Scientific, Waltham, MA, USA), alpha-minimum essential medium (GibcoÒ; Thermo Fisher Scientific), sodium bicarbonate (NaHCO 3 ; Sigma-Aldrich Co.), hydrochloric acid (HCl; 36.5%–38%; J.T. BakerÒ; Avantor Performance Materials, Center Valley, PA, USA), penicillin (10,000 units/mL; Gibco), streptomycin (10,000 µ g/mL; Gibco), recombinant mouse RANKL/Trance (R&D systems, Inc., Minneapolis, MN, USA), dimethyl sulfoxide (99%; J.T. BakerÒ; Avantor Performance Mate- rials), phosphate-buffered saline (PBS; potassium phosphate [KH 2 PO 4 ; Sigma-Aldrich Co.], potassium chloride [KCl; Sigma-Aldrich Co.], sodium phosphate dibasic [Na 2 HPO 4 ; Sigma-Aldrich Co.], sodium chloride [NaCl; Sigma-Aldrich Co.]), and 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazo- lium bromide (MTT; Sigma-Aldrich Co.). All products and liquids were prepared in laminar flow under sterile conditions. All animal studies were performed with the approval of Insti- tutional Animal Care and Use Committee and followed the guidelines of the Council of Agriculture, Taiwan.