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101.
Targeted drug delivery is a promising approach to overcome the limitations of classical chemotherapy. In this respect, Imatinib‐loaded chitosan‐modified magnetic nanoparticles were prepared as a pH sensitive system for targeted delivery of drug to tumor sites by applying a magnetic field. The proposed magnetic nanoparticles were prepared through modification of magnetic Fe3O4 nanoparticles with chitosan and Imatinib. The structural, morphological and physicochemical properties of the synthesized nanoparticles were determined by different analytical techniques including energy‐dispersive X‐ray spectroscopy (EDS), field emission scanning electron microscopy (FESEM), Fourier‐transform infrared (FTIR) spectroscopy, high resolution transmission electron microscopy (HR‐TEM), vibrating sample magnetometry (VSM), X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). UV/visible spectrophotometry was used to measure the Imatinib contents. Thermal stability of the prepared particles was investigated and their efficiency of drug loading and release profile were evaluated. The results demonstrated that Fe3O4@CS acts as a pH responsive nanocarrier in releasing the loaded Imatinib molecules. Furthermore, the Fe3O4@CS/Imatinib nanoparticles displayed cytotoxic effect against MCF‐7 breast cancer cells. Results of this study can provide new insights in the development of pH responsive targeted drug delivery systems to overcome the side effects of conventional chemotherapy. 相似文献
102.
Iman Jafari Mohamadreza Shakiba Fatemeh Khosravi Seeram Ramakrishna Ehsan Abasi Ying Shen Teo Mohammadreza Kalaee Majid Abdouss Ahmad Ramazani S. A Omid Moradi Erfan Rezvani Ghomi 《Molecules (Basel, Switzerland)》2021,26(6)
The incorporation of nanofillers such as graphene into polymers has shown significant improvements in mechanical characteristics, thermal stability, and conductivity of resulting polymeric nanocomposites. To this aim, the influence of incorporation of graphene nanosheets into ultra-high molecular weight polyethylene (UHMWPE) on the thermal behavior and degradation kinetics of UHMWPE/graphene nanocomposites was investigated. Scanning electron microscopy (SEM) analysis revealed that graphene nanosheets were uniformly spread throughout the UHMWPE’s molecular chains. X-Ray Diffraction (XRD) data posited that the morphology of dispersed graphene sheets in UHMWPE was exfoliated. Non-isothermal differential scanning calorimetry (DSC) studies identified a more pronounced increase in melting temperatures and latent heat of fusions in nanocomposites compared to UHMWPE at lower concentrations of graphene. Thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) revealed that UHMWPE’s thermal stability has been improved via incorporating graphene nanosheets. Further, degradation kinetics of neat polymer and nanocomposites have been modeled using equations such as Friedman, Ozawa–Flynn–Wall (OFW), Kissinger, and Augis and Bennett’s. The "Model-Fitting Method” showed that the auto-catalytic nth-order mechanism provided a highly consistent and appropriate fit to describe the degradation mechanism of UHMWPE and its graphene nanocomposites. In addition, the calculated activation energy (Ea) of thermal degradation was enhanced by an increase in graphene concentration up to 2.1 wt.%, followed by a decrease in higher graphene content. 相似文献
103.
Rajaei Amir Jafari Mohammad Ghani Kamal 《Journal of Thermal Analysis and Calorimetry》2020,142(3):1295-1302
Journal of Thermal Analysis and Calorimetry - The decomposition onset temperature, Tdecom, is an important parameter for investigating the thermal stability of chemicals. A novel method is... 相似文献
104.
Safa Raziyeh Soltani Goharrizi Ataallah Jafari Saeed Jahanshahi Javaran Ebrahim 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2497-2514
Journal of Thermal Analysis and Calorimetry - In the present study, double-diffusive mixed convection related to the heat and mass transfer of the solid particles dissolution in a shear flow was... 相似文献
105.
Jafari Mohammad Farajollahi Amir Gazori Heshmatollah 《Journal of Thermal Analysis and Calorimetry》2021,144(1):167-178
Journal of Thermal Analysis and Calorimetry - In the present study, a new swirling flow generator is studied which aims to enhance the convective heat transfer rate in a heat exchanger tube. This... 相似文献
106.
Ebrahimi-Moghadam Amir Deymi-Dashtebayaz Mahdi Jafari Hosein Niazmand Amir 《Journal of Thermal Analysis and Calorimetry》2020,141(6):2573-2588
Journal of Thermal Analysis and Calorimetry - The energy consumption and greenhouse gases emissions in natural gas city gate stations are important issues in the natural gas industry. In order to... 相似文献
107.
Esmaeil Jafari 《Russian Journal of Electrochemistry》2021,57(6):663-670
Russian Journal of Electrochemistry - Corrosion resistance is one of the essential factors in metal selection and can be enhanced greatly by coatings. The corrosion resistance of the electroless... 相似文献
108.
Foroutannia Ali Ghasemi Mahdieh Parastesh Fatemeh Jafari Sajad Perc Matjaž 《Nonlinear dynamics》2020,100(3):2699-2714
Nonlinear Dynamics - The brain is a complex system consisting of a large number of interacting neurons. Recently, a simple nonlinear biological model has been proposed for the up and down state... 相似文献
109.
Habib Firouzabadi Nasser Iranpoor Abbas Ali Jafari Somayeh Makarem 《Journal of molecular catalysis. A, Chemical》2006,250(1-2):237-242
AlPW12O40 as a recyclable Lewis acid and stable solid compound was introduced for efficient ring opening of different epoxides with thiols, acetic acid, and primary, secondary, and tertiary alcohols. These processes were carried out at room temperature with high regio- and stereoselectivity. 相似文献
110.
Vocal perturbation, harmonics-to-noise, and intensity measures were obtained for 10 subjects during three experimental tasks: (a) prolonged /a/, (b) /pa/ with vowel prolonged, and (c) same as (b) with subjects wearing a pneumotachographic mask and oral pressure tube inserted between the lips. There were no statistically significant differences among the experimental conditions for any of the measures. The findings suggest that a single task may be used to obtain airflow, oral pressure, and acoustic measures of vocal performance. Observed differences in jitter and harmonic-to-noise means for the male and female speakers are discussed. 相似文献