99mTc-anionic linear globular dendrimer-G2-phenylalanine conjugate: Novel brain tumor SPECT imaging

The purpose of this study was the investigation of the targeting potential of99mTc-Labeled dendrimer-phenylalanine conjugate for brain tumor SPECT imaging. L-Type amino acid transporters (LAT1) are highly expressed in the blood-brain barrier as well as in brain cancer cells; thus, targeting LAT1 using phenylalanine could improve the sensitivity and specificity of radiosynthesis nanocarrier. In this study, the dendrimer G2�phenylalanine conjugate was synthesized and characterized by Fourier transform infrared spectroscopy, atomic force microscopy, particle size, and zeta potential. MTT assay was done for cell viability measurement in different concentrations of nanoparticles (0.125, 0.25, 0.5 mg/ml) on C6 glioma cell lines; the uptake study was evaluated using fluorescence-activated cell sorter (FACS) instrument; finally, SPECT scintigraphy in glioma tumor-bearing Wistar rats was done. The dendrimer-phenylalanine conjugate particle size was found in the range of 74.14±2.2 to 109±3.1 nm, with a slightly negative surface charge. Also, phenylalanine present on the dendrimer's surface� phenylalanine conjugate enhanced the dendrimer's cellular uptake�phenylalanine conjugate on the C6 glioma cell line. Results of SPECT imaging and fluorescence studies revealed that dendrimer� phenylalanine conjugate accumulated into the brain tumor cells, and it can be suggested as a promising brain-targeting probe with no toxicity in brain tumor imaging. © 2020 by the authors

Effective parameters on conductivity of mineralized carbon nanofibers: an investigation using artificial neural networks

The aim of this study was to predict the effects of different parameters on the conductivity of mineralized PAN-based carbon nanofibers by the artificial neural network (ANN) method. The conductivity of CNFs was investigated as a function of various parameters, including simulated body fluid (SBF) concentration, immersion time and CNFs diameter. In order to conduct ANN modeling, the considered parameters and experimental outputs were categorized into (i) training, (ii) validating and (iii) testing datasets, which were subsequently analyzed using three different training algorithms, including scaled conjugate gradient, Bayesian regularization, and Levenberg-Marquardt back-propagation. The comparison study between three artificial neural network models indicates that all back-propagation methods could be employed to estimate the cathodic current accurately. The results of cyclic voltammetry demonstrated that the cathodic current increased as a function of decreasing simulated body fluid concentration, immersion time and carbon nanofiber diameter. The Pearson correlation coefficients were significant at less than the 0.01 level for all prediction models. Among the studied algorithms, the scaled conjugate gradient back-propagation method produced the highest R-value at 0.92. Based on the promising results of the current approach, the mineralized CNFs can be tailored in a way to construct electro-conductive scaffolds capable of manipulating the activities of bone cells through electrical stimulation and could be utilized in bone tissue engineering

Tumor-associated macrophages and epithelial�mesenchymal transition in cancer: Nanotechnology comes into view

Tumor-associated macrophages (TAMs) are an important component of the leukocytic infiltrate of the tumor microenvironment. There is persuasive preclinical and clinical evidence that TAMs induce cancer inanition and malignant progression of primary tumors toward a metastatic state through a highly conserved and fundamental process known as epithelial�mesenchymal transition (EMT). Tumor cells undergoing EMT are distinguished by increased motility and invasiveness, which enable them to spread to distant sites and form metastases. In addition, besides becoming resistant to apoptosis and antitumor drugs, they also contribute to immunosuppression and get a cancer stem-cell like phenotype. Here, we will focus on selected molecular pathways underlying EMT�in particular, the role of TAMs in the induction and maintenance of EMT�and further discuss how the targeting of TAMs through the application of nanotechnology tools allows the development of a whole new range of therapeutics. © 2018 Wiley Periodicals, Inc

Cross-linking gold nanoparticles aggregation method based on localised surface plasmon resonance for quantitative detection of miR-155

MiR-155 plays a critical role in the formation of cancers and other diseases. In this study, the authors aimed to design and fabricate a biosensor based on cross-linking gold nanoparticles (AuNPs) aggregation for the detection and quantification of miR-155. Also, they intended to compare this method with SYBR Green real-time polymerase chain reaction (PCR). Primers for real-time PCR, and two thiolated capture probes for biosensor, complementary with miR-155, were designed. Citrate capped AuNPs (18.7 ± 3.6 nm) were synthesised and thiolated capture probes immobilised to AuNPs. The various concentrations of synthetic miR-155 were measured by this biosensor and real-time PCR method. Colorimetric changes were studied, and the calibration curves were plotted. Results showed the detection limit of 10 nM for the fabricated biosensor and real-time PCR. Also, eye detection using colour showed the weaker detection limit (1 µM), for this biosensor. MiR-133b as the non-complementary target could not cause a change in both colour and UV�visible spectrum. The increase in hydrodynamic diameter and negative zeta potential of AuNPs after the addition of probes verified the biosensor accurately fabricated. This fabricated biosensor could detect miR-155 simpler and faster than previous methods. © The Institution of Engineering and Technology 2017

Cross-linking gold nanoparticles aggregation method based on localised surface plasmon resonance for quantitative detection of miR-155

MiR-155 plays a critical role in the formation of cancers and other diseases. In this study, the authors aimed to design and fabricate a biosensor based on cross-linking gold nanoparticles (AuNPs) aggregation for the detection and quantification of miR-155. Also, they intended to compare this method with SYBR Green real-time polymerase chain reaction (PCR). Primers for real-time PCR, and two thiolated capture probes for biosensor, complementary with miR-155, were designed. Citrate capped AuNPs (18.7 ± 3.6 nm) were synthesised and thiolated capture probes immobilised to AuNPs. The various concentrations of synthetic miR-155 were measured by this biosensor and real-time PCR method. Colorimetric changes were studied, and the calibration curves were plotted. Results showed the detection limit of 10 nM for the fabricated biosensor and real-time PCR. Also, eye detection using colour showed the weaker detection limit (1 µM), for this biosensor. MiR-133b as the non-complementary target could not cause a change in both colour and UV�visible spectrum. The increase in hydrodynamic diameter and negative zeta potential of AuNPs after the addition of probes verified the biosensor accurately fabricated. This fabricated biosensor could detect miR-155 simpler and faster than previous methods. © The Institution of Engineering and Technology 2017

Development of electrically conductive hybrid nanofibers based on CNT-polyurethane nanocomposite for cardiac tissue engineering

Conductive nanofibers have been considered as one of the most interesting and promising candidate scaffolds for cardiac patch applications with capability to improve cell-cell communication. Here, we successfully fabricated electroconductive nanofibrous patches by simultaneous electrospray of multiwalled carbon nanotubes (MWCNTs) on polyurethane nanofibers. A series of CNT/PU nanocomposites with different weight ratios (2:10, 3:10, and 6:10wt%) were obtained. Scanning electron microscopy, conductivity analysis, water contact angle measurements, and tensile tests were used to characterize the scaffolds. FESEM showed that CNTs were adhered on PU nanofibers and created an interconnected web-like structures. The SEM images also revealed that the diameters of nanofibers were decreased by increasing CNTs. The electrical conductivity, tensile strength, Young's modulus, and hydrophilicity of CNT/PU nanocomposites also enhanced after adding CNTs. The scaffolds revealed suitable cytocompatibility for H9c2 cells and human umbilical vein endothelial cells (HUVECs). This study indicated that simultaneous electrospinning and electrospray can be used to fabricate conductive CNT/PUnanofibers, resulting in better cytocompatibility and improved interactions between the scaffold and cardiomyoblast

Anti-inflammatory effects of eugenol nanoemulsion as a topical delivery system

Eugenol is the main constituent of clove oil with anti-inflammatory properties. In this work, for the first time, O/W nanoemulsion of eugenol was designed for the evaluation of anti-inflammatory effects as a topical delivery system. Topical formulations containing 1, 2 and 4 of eugenol as well as a nanoemulsion system containing 4 eugenol and 0.5 piroxicam were prepared. Further to physicochemical examinations, such as determination of particle size, polydispersity index, zeta potential and physical stability, anti-inflammatory activity was examined in carrageenan-induced paw edema in rats. The optimum formulation was found to contain 2 eugenol (oil phase), 14 Tween 20 (surfactant) and 14 isopropyl alcohol (co-surfactant) in water. Nanoemulsion with polydispersity index of 0.3 and median droplet diameter of 24.4 nm (d50) was obtained. Animal studies revealed that the nanoemulsions exhibited significantly improved anti-inflammatory activity after 1.5 h, compared with marketed piroxicam gel. Additionally, it was shown that increasing the concentration of eugenol did not show higher inhibition of inflammation. Also, the nanoemulsion having piroxicam showed less anti-inflammatory properties compared with the nanoemulsion without piroxicam. © 2015 Taylor & Francis