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The purpose of this work was to investigate the performance of electrodes synthesized with Polyacrylonitrile-based carbon nanofibers (PAN-based CNFs). The homogenous PAN solutions with different concentrations were prepared and electrospun to acquire PAN nanofibers and then CNFs were fabricated by heat treatment. The effective parameters for the production of electrospun CNF electrode were investigated. Scanning electron microscopy (SEM) was used to characterize electrospun nanofibers. Cyclic voltammetry was applied to investigate the changes of behavior of electrospun CNF electrodes with different diameters. The structure of CNFs was also evaluated via X-ray diffraction (XRD) and Raman spectroscopy. The results exhibited that diameter of nanofibers reduced with decreasing polymer concentration and applied voltage and increasing tip-to-collector distance, while feeding rate did not have significant effect on nanofiber diameter. The investigations of electrochemical behavior also demonstrated that cyclic voltammetric response improved as diameter of CNFs electrode decreased. [ABSTRACT FROM AUTHOR]

[Display omitted] This study aims to overcome physiological barriers and increase the therapeutic index for the treatment of glioblastoma (GBM) tumors by using Paclitaxel (PTX) loaded Poly(lactic co-glycolic acid) nanoparticles (PTX-PLGA-NPs) and Doxorubicin (DOX) loaded Poly (lactic co-glycolic acid) nanoparticles (DOX-PLGA-NPs). The hydrodynamic diameter of nanoparticles (NPs) was characterized by dynamic light scattering (DLS) which was 94 ± 4 nm and 133 ± 6 nm for DOX-PLGA-NPs, and PTX-PLGA-NPs, respectively. The zeta potential for DOX-PLGA-NPs and PTX-PLGA-NPs were −15.2 ± 0.18 mV and −17.3 ± 0.34 mV, respectively. The cytotoxicity of PTX-PLGA-NPs and DOX-PLGA-NPs was augmented compared to DOX and PTX on C 6 GBM cells. The Lactate dehydrogenase (LDH) tests for various formulations were carried out. The results indicated that the amount of released LDH was 262 ± 7.84 U.L-1 at the concentration of 2 mg/mL in the combination therapy, which was much higher than other groups (DOX-PLGA-NPs (210 ± 6.92 U.L-1), PTX-PLGA-NPs (201 ± 8.65 U.L-1), DOX (110 ± 9.81 U.L-1), PTX (95 ± 5.02 U.L-1) and PTX + DOX (67 ± 4.89 U.L-1)). MRI results of the combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs indicated that GBM tumor size decreased considerably compared to the other formulations. Also, combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs demonstrated a longer median survival of more than 80 days compared to PTX (38 days), DOX (37 days) and PTX + DOX (48 days), PTX-NPs (58 days) and DOX-NPs (62 days). The results of locomotion, body weight, rearing and grooming assays indicated that combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs had the most positive effect on the movements of rats compared to the other formulations. [ABSTRACT FROM AUTHOR]

[Display omitted] • An electrochemical aptasensor was designed to detect Acinetobacter baumannii in urine samples. • This aptasensor can detect Acinetobacter baumannii faster compared to the conventional method. • The stability of this aptasensor for 30 days was acceptable. Acinetobacter baumannii (A. baumannii) is a gram-negative bacterium that is responsible for causing a range of infections, including pneumonia, meningitis, and bloodstream infections and the detection of this bacterium is crucial for timely diagnosis and treatment of infections. The purpose of this work was to design and manufacture an electrochemical biosensor based on carbon nanofibers (CNFs), gold nanoparticles (AuNPs), and aptamer that could detect A. baumannii in urine samples. At first, polyacrylonitrile (PAN) polymer was electrospun and CNFs were formed during two stages of heat treatment including stabilization and carbonization, and Raman spectroscopy and X-ray diffraction (XRD) were used to characterize it. Then, these CNFs were used to modify the surface of the screen-printed carbon electrode (SPCE), and AuNPs were placed on the SPCE modified with CNFs using the electrodeposition method. Field emission scanning electron microscopy (FESEM) and energy dispersive X-Ray spectroscopy (EDS) were used to study the surface morphology of the modified electrode to determine the carbon and gold elements, respectively. Then the aptamer related to A. baumannii was placed on this modified electrode using a simple and cost-effective process and characterized by the cyclic voltammetry (CV) technique. Next, the spiked A. baumannii in urine samples was detected by this aptasensor in the range of 101 to 106 cfu mL−1 and limit of detection (LOD) to 0.681 cfu mL−1 with differential pulse voltammetry (DPV) technique. Salmonella typhimurium, Staphylococcus aureus and E. Coli were used to perform the selectivity test. In addition, its repeatability was checked and its stability for 30 days was more than 96 %. Finally, the results of this aptasensor were compared with the conventional method of bacterial culture, and this aptasensor was able to detect A. baumannii in a less time and with more sensitivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • A molecularly imprinted electrochemical sensor accurately measures Amiodarone, a drug with a narrow therapeutic window. • The sensor successfully determines Amiodarone concentrations, potential for pharmaceutical analysis and clinical applications. • The optimized sensor exhibits linearity, reproducibility, precision, and accuracy in Amiodarone detection. • The imprinted electrochemical sensor provides efficient quantification of Amiodarone in real samples. Amiodarone, a drug associated with significant cardiac, pulmonary, hepatic, and neurological complications, requires accurate measurement due to its narrow therapeutic window. However, the current analysis methods are time-consuming, complex, and expensive. Thus, there is a pressing need to develop a cost-effective and rapid solution for Amiodarone determination. In this study, a molecularly imprinted electrochemical sensor was designed, fabricated, and evaluated to detect Amiodarone precisely. The research involved the synthesis of magnetic nanoparticles coated with silica and the subsequent synthesis of a molecularly imprinted polymer. Carbon nanofibers were then prepared through electrospinning in a polyacrylonitrile furnace, onto which the molecularly imprinted polymer was placed. Multiple concentrations of Amiodarone were successfully determined utilizing this sensor. Following optimization, the designed sensor exhibited desirable traits such as linearity, reproducibility, precision, and accuracy. The sensor detection and quantification limit proved acceptable in whole blood and plasma samples. With its remarkable reproducibility and accurate detection of low concentrations, this molecularly imprinted electrochemical sensor offers a reliable method for quantifying Amiodarone in real samples. Moreover, its swift voltammetric response outperforms existing techniques regarding time efficiency. Overall, the developed sensor presents a valuable advancement and has the potential to benefit pharmaceutical analysis and clinical applications greatly. [ABSTRACT FROM AUTHOR]

The aim of this study was to prepare folate-targeted Erlotinib loaded human serum albumin nanoparticles (FA-ERL-HSA NPs) and investigate in vitro cytotoxic and apoptotic effects using cell lines (U87MG and C6 cells) and an in vivo rat bearing C6 glioma model. The mean size of the FA-ERL-HSA NPs prepared using a desolvation method was 135 nm. In vitro MTT assays demonstrated that FA-ERL-HSA NPs had an IC 50 value of 52.18 μg/mL and 17.53 μg/mL compared to free ERL which had an IC 50 value of 119.8 μg/mL and 103.2 μg/mL for U87MG and C6 cells for 72 h, respectively. Flow cytometry results showed the apoptosis rate with FA-ERL-HSA NPs (100 μg/mL, 72 h) was higher compared to free ERL for both U87MG and C6 cells. Experiments using a rat glioblastoma model via TUNEL assay indicated that the apoptosis index of FA-ERL-HSA NPs was 48 % compared to 21 % for free ERL and the tumor size effectively decreased after a daily injection of 220 μg (2.5 mg/kg) from 87.45 mm3 (19th day) to 1.28 mm3 (60th day). The median survival rate of the rats increased after treatment to >100 days which was greater than controls. [ABSTRACT FROM AUTHOR]

Glioblastoma is a malignant brain tumor and leads to death in most patients. Chemotherapy is a common method for brain cancer in clinics. However, the recent advancements in the chemotherapy of brain tumors have not been efficient enough. With the advancement of nanotechnology, the used drugs can enhance chemotherapy efficiency and increase the access to brain cancers. Combination of therapeutic agents has been recently attracted great attention for glioblastoma chemotherapy. One of the early benefits of combination therapies is the high potential to provide synergistic effects and decrease adverse side effects associated with high doses of single anticancer drugs. Therefore, brain tumor treatments with combination drugs can be considered as a crucial approach for avoiding tumor growth. This review investigates current progress in nano-mediated co-delivery of therapeutic agents with focus on glioblastoma chemotherapy prognosis. [ABSTRACT FROM AUTHOR]

[Display omitted] The aim of this work is to co-load paclitaxel (PTX) and etoposide (ETP) in methoxy poly(ethylene glycol)-poly(lactic-co-glycolic acid) nanoparticles (mPEG-PLGA NPs) to overcome pharmacokinetics and physiological limitations and enhance therapeutic efficacy for treating intracranial glioblastoma. Both drugs were loaded into mPEG-PLGA NPs by a nano-precipitation method. The resultant NPs demonstrated an enhanced cytotoxic effect indicated by lower IC 50 values and augmented cell apoptosis to U87 and C6 glioma cell lines compared to both free drugs. Additionally, blood compatibility assays showed that the PTX/ETP co-loaded mPEG-PLGA NPs did not induce blood hemolysis, blood clotting, or platelet aggregation. In vivo anti-glioma efficacy evaluation in rats bearing intracranial C6 glioma revealed a superior anti-glioma activity for the treatment with PTX/ETP co-loaded mPEG-PLGA NPs compared to other formulations, particularly a significantly longer median survival, 76 days compared to 36 days for free PTX and 37 days for free ETP treatment, respectively, and higher tumor regression, proved by magnetic resonance imaging (MRI). [ABSTRACT FROM AUTHOR]

The aim of this study was to improve the therapeutic index of chemotherapeutic drugs on glioblastoma cells through an improved co-drug delivery system. Methotrexate (MTX) and paclitaxel (PTX) were co-loaded into poly (lactic- co -glycolic acid) nanoparticles (PLGA NPs) coated with polyvinyl alcohol (PVA) and Poloxamer188 (P188). The mean size of the NPs was about 212 nm, with a zeta potential of about −15.7 mV. Encapsulation efficiency (EE%) and drug loading (DL%) were determined to be 72% and 4% for MTX and 85% and 4.9% for PTX, respectively. The prepared NPs were characterized by differential thermal analysis (DTA) and thermogravimetric analysis (TGA). Moreover, an in vitro sustained release profile was observed for both drug loaded PLGA NPs. Glioblastoma cellular uptake of the NPs was confirmed by fluorescence microscopy and cell survival rate was investigated through the 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method after 48 h of incubation showing IC 50 values of 24.5 μg·mL−1 for PTX and 9.5 μg·mL−1 for MTX for the MTX/PTX co-loaded PLGA nanoparticles coated with PVA/P188 (Co-2 NPs). Apoptosis and necrosis were also studied via flow cytometry, the lactate dehydrogenase (LDH) assay and the amount of anti-apoptotic protein (Bcl-2) expression. Blood compatibility of the co-delivery of PTX and MTX loaded PLGA NPs was investigated using a hemolysis method as well. The co-delivery of PTX and MTX loaded PLGA NPs is promising for the treatment of glioblastoma compared to their respective free drug formulations and, thus, should be further investigated. [ABSTRACT FROM AUTHOR]