Nanobiotechnology / Bionanotechnology / Nanobiology
Mah Monir Karimzade; Ladan Rashidi; Fariba Ganji; Mitra Ahmadi; Sattar Tahmasebi Enferadi
Volume 8, Issue 4 , February 2015, , Pages 385-398
Abstract
The aim of this research is the preparation of a system based on mesoporous silica nanoparticles (MSN) for delivery of Rivastigmine hydrogen tartrate and investigating of the system cytotoxicity, with or without drugs, on the human brain neuroblastoma cells (SY5Y). Rivastigmine is a hydrophilic and a ...
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The aim of this research is the preparation of a system based on mesoporous silica nanoparticles (MSN) for delivery of Rivastigmine hydrogen tartrate and investigating of the system cytotoxicity, with or without drugs, on the human brain neuroblastoma cells (SY5Y). Rivastigmine is a hydrophilic and a hydrophobic drug which is used for treatment of Alzimerʾs disease. In this study MSN were synthesized and characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, x-ray diffraction, N2 adsorption isotherms, and z-potential analysis. Results showed that all MSN were spherical with the same structure. The mean size of nanoparticles was 100±13 nm and the mean diameter of pores was 2.15 nm. The loading capacity and efficiency of rivastigmine hydrogen tartrate were obtained 20.88, and 25%, respectively. Release of rivastigmine from nanoparticles in the simulated gastric and body fluid during 24 h were obtained 70.5 and 79.6%, respectively, which was shown the slightly fast release of rivastigmine in simulated gastric fluid. The cytotoxicity effect of nanoparticles with and without rivastigmine was done by MTT assay on SY5Y cell lines. Results showed that the in vitro rivastigmine release from the nanoparticles containing of it exhibited the more treatment property as free rivastigmine on SY5Y.
Targeted Drug Delivery / Smart Drug Delivery / Drug Targeting
Vahid Khandan; Bahar Firoozabadi; Mohammad Saeid Saeidi
Volume 8, Issue 3 , September 2014, , Pages 229-239
Abstract
A hallmark of Alzheimer disease (the most common type of dementia in the elderly) is the aggregation and deposition of toxic species ranging from small soluble oligomers to insoluble fibril plaques of Amyloid-Beta protein originates from the cleavage of APP by Beta and Gama Secretase (Amyloid Hypothesis). ...
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A hallmark of Alzheimer disease (the most common type of dementia in the elderly) is the aggregation and deposition of toxic species ranging from small soluble oligomers to insoluble fibril plaques of Amyloid-Beta protein originates from the cleavage of APP by Beta and Gama Secretase (Amyloid Hypothesis). An attractive therapeutic approach to treat AD is to identify small ligands capable of binding to A-Beta monomers and reverse its amyloidosis process. Here, a peptide drug having the sequence of GLMVG which has been derived from the C-terminal of A-Beta was used as breaker for a monomer of Beta sheet rich structure. The combination of Docking and Molecular Dynamics methods were used for simulation of drug-receptor interaction. This simulation implied that pentapeptide altered secondary structure of A-Beta monomer and declined its stability. This study proved that pentapeptide is capable to reverse Beta-sheet formation and can be considered as an AD drug in other preclinical studies.
Targeted Drug Delivery / Smart Drug Delivery / Drug Targeting
Fariba Ganji; Fateme Hoobakht; Farzane Ghasemi Tahrir; Ebrahim Vasheghani-Farahani
Volume 8, Issue 3 , September 2014, , Pages 249-260
Abstract
Somanis one of the strongest nerve agents and treatment of poisoning with Soman is difficult and time-critical. Pyridostigmine bromide is an inhibitor of cholinesterase used for protecting against toxicity by Soman. In this study, a new injectable thermosensitive sustained release dosage form of pyridostigmine ...
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Somanis one of the strongest nerve agents and treatment of poisoning with Soman is difficult and time-critical. Pyridostigmine bromide is an inhibitor of cholinesterase used for protecting against toxicity by Soman. In this study, a new injectable thermosensitive sustained release dosage form of pyridostigmine bromide was achieved by chitosan/glycerolphosphate solution. In this study, thermosensitivity and rheological properties of chitosan solution (2% w/v) in aqueous hydrochloric acid (0.1 molar) with different percent of glycerolphosphate salt as well as the release profile of pyridostigmine bromide have been investigated. It was observed that increasing the glycerolphosphate salt concentration would increase the pH of chitosan solution, while decrease its gelation time and loss or storage modulus. It was also observed that glycerolphosphate salt concentration has direct effect on hydrogel thermoreversibility. The presented results indicated that hydrogel containing 2% w/v of chitosan and 16% w/v of glycerolphosphate salt could sustain the delivery of pyridostigmine bromide, through Fickian diffusion, up to four days.
Targeted Drug Delivery / Smart Drug Delivery / Drug Targeting
Zohre Goodarzi; Bahman Ebrahimi Hosein zadeh; Morteza Maghrebi; Alireza Fakhari Zavareh; Mohammad Barshan; Hosein Shaki
Volume 7, Issue 2 , June 2013, , Pages 133-141
Abstract
Nicotine can be measured electrochemically using Cu nanoparticles and CNT-modified glassy carbon electrode. The slow electrochemical oxidation makes it difficult to measure the concentration of nicotine electrochemically using normal electrodes.To improve the oxidation rate, different mediators and chemically ...
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Nicotine can be measured electrochemically using Cu nanoparticles and CNT-modified glassy carbon electrode. The slow electrochemical oxidation makes it difficult to measure the concentration of nicotine electrochemically using normal electrodes.To improve the oxidation rate, different mediators and chemically modified electrodes have been used. In this experiment, concentration of nicotine in aqueous solution was determined using MWCNT-modified glassy carbon electrode in presence of copper nanoparticles (Cu NPs) as mediator. For this purpose, the glassy carbon electrode (GCE) was modified with suspended MWCNT in dimethylformamaide and Cu NPs was electrochemically deposited on MWCNT-GCE subsequently. Also, experimental parameters affecting the deposition of Cu NPs on MWCNT-GCE such as cycles, copper salt concentration and scan rate were found to be optimum at 20 cycles, 1.75 μmol L-1 and 100 mVs-1 respectively. Finally, the modified electrode was characterized by cyclic voltammetry and successfully used to measure the concentration of nicotine in aqueous solution.
Targeted Drug Delivery / Smart Drug Delivery / Drug Targeting
Seyed Ali Naghi Ahmadi; Tahere Fanaei Sheykhol-Eslami; Mehri Mehrjoo; Morteza Maleki
Volume 7, Issue 4 , June 2013, , Pages 351-360
Abstract
A secure self-biased remote controller for a drug delivery system, working at 956 MHz, is designed using piezoelectric substrate containing an implantable micropump. For this purpose, the effect of Lithium Niobate substrate on the actuation voltage, signal to noise ratio, insertion loss, bandwidth, and ...
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A secure self-biased remote controller for a drug delivery system, working at 956 MHz, is designed using piezoelectric substrate containing an implantable micropump. For this purpose, the effect of Lithium Niobate substrate on the actuation voltage, signal to noise ratio, insertion loss, bandwidth, and real and imaginary part of the admittance are investigated. The results of analytical calculation and numerical simulation show that the actuation voltage of the Lithium Niobate substrate is about 5.8 V, and the calculated bandwidth is 160 MHz with the signal to noise ratio of 26.52 dB. The security for actuation of the device is assured with Barker code. The insertion loss is equal to 2.1 dB which is adequate for maximum power transfer. Numerical simulation indicates that the generated voltage could create a displacement about 9.3353 nm in the conductive diaphragm, which is enough to ascertain the correct drug delivery by the micropomp. According to the analytical calculations and numerical simulations, the performance of the designed controller is qualified to correctly stimulate the drug delivery device.
Targeted Drug Delivery / Smart Drug Delivery / Drug Targeting
Mohammad Koohimoghadam; Adel Torkamaan Rahmani
Volume 5, Issue 4 , June 2011, , Pages 333-351
Abstract
Discovery of new drugs and study of their side effects has been an important research field in recent years. Because of direct effect of the pharmaceutical products on human health usually the drug design projects are challenging and technically demanding. The incorporation of computer simulations into ...
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Discovery of new drugs and study of their side effects has been an important research field in recent years. Because of direct effect of the pharmaceutical products on human health usually the drug design projects are challenging and technically demanding. The incorporation of computer simulations into drug design projects is one of the best ways to optimize drugs' potency. In this approach, researchers try to find the best interaction between protein structure and drug in a virtual environment; this procedure is called "molecular docking". The molecular docking problem can be considered as a search problem. The search space in this problem is defined with all possible protein-ligand interactions and the best interaction is the solution of problem. In this paper, a new approach for finding the best interaction is proposed. The proposed method is based on opposition based differential evolution algorithm. Also the proposed method is enhanced by a local search algorithm and a pseudo-elitism operator. Like other metaheuristic algorithms, our method uses a population of possible solution and AutoDock scoring function is used to evaluate each vector in the population. Six different protein-ligand complexes are used to verify the efficiency of the proposed algorithm. The experimental results show that the proposed algorithm is more robust and reliable than other algorithms such as simulated annealing and Lamarckian genetic algorithm.
Targeted Drug Delivery / Smart Drug Delivery / Drug Targeting
Nadia Naghavi; Amene Sazgarnia; Mohammad Hossein Miranbaygi
Volume 4, Issue 3 , June 2010, , Pages 209-218
Abstract
Today, the idea of photodynamic therapy (PDT) is considered as one of the fundamental basis of the new cancer treatment methods. One of the important issues in the application of this therapy is choosing the optimal dosimetry method. At best, PDT dosimetry should be done based on estimation of the accumulated ...
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Today, the idea of photodynamic therapy (PDT) is considered as one of the fundamental basis of the new cancer treatment methods. One of the important issues in the application of this therapy is choosing the optimal dosimetry method. At best, PDT dosimetry should be done based on estimation of the accumulated singlet oxygen dose within the target tissue and comparison with the threshold value to ensure the efficacy of the treatment. In order to estimate the accumulated singlet oxygen level within the tissue, the most appropriate method is modeling the process of treatment. In this context, it is necessary to obtain enough information about the drug concentration within the target tissue, the amount of light absorbed by the drug, the amount of oxygen into the tissue, and the interactions between them that produce singlet oxygen. In this study modeling and simulation of the photobleaching has been investigated, considering the importance of the level of drug concentration in the target tissue which would be decreased by photobleaching. Simulation was done with Matlab software. A Comparison of simulation results with those of experimental methods showed that in the state of non-uniform drug distribution, simulation follows experimental results at the initial phase of rapid decline of drug concentration.
Targeted Drug Delivery / Smart Drug Delivery / Drug Targeting
Seyede Sara Shafiei; Mehran Solati Hashjin; Mehrnaz Salarian
Volume 3, Issue 2 , June 2009, , Pages 119-125
Abstract
Layered double hydroxides (LDHs) are layered solid materials having positively charged layers. A variety of negatively charged biomolecules can be hybridized with LDHs to evolve into bio-LDH Nano hybrids, including vitamins, drugs and DNA strands as well as simple organic acids. In this research, Mg-Al-LDH ...
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Layered double hydroxides (LDHs) are layered solid materials having positively charged layers. A variety of negatively charged biomolecules can be hybridized with LDHs to evolve into bio-LDH Nano hybrids, including vitamins, drugs and DNA strands as well as simple organic acids. In this research, Mg-Al-LDH containing drug was synthesized by coprecipitation and anion exchange methods. The LDH structure was characterized by X-Ray Diffraction XRD, FTIR, SEM and STA techniques. The in vitro release profile of nano hybrids was analyzed by UV spectrophotometer. It was concluded that the present biocompatible hydrotalcite-like compound can be an excellent host material for encapsulating Ibuprofen and can play a role as a delivery vehicle for a controlled release.
Targeted Drug Delivery / Smart Drug Delivery / Drug Targeting
Fariba Ourang; Mohammad Rafienia
Volume -1, Issue 2 , June 2005, , Pages 173-179
Abstract
Polyurethane micro spheres have been synthesized by solvent evaporation technique with castor oil, Polycaprolacton (PCL), Hexamethylen diisocyanate (HMDI) and Ethyl diamine (ED) as carriers for controlled drug delivery systems. Release behavior of micro spheres has been investigated using Bromocresol ...
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Polyurethane micro spheres have been synthesized by solvent evaporation technique with castor oil, Polycaprolacton (PCL), Hexamethylen diisocyanate (HMDI) and Ethyl diamine (ED) as carriers for controlled drug delivery systems. Release behavior of micro spheres has been investigated using Bromocresol purple die. Fourier transmission infrared (FTIR), Scanning Electron Microscope (SEM), Optical microscope, dissolution instrument and UV spectrophotometer were used to investigate the polymerization process, surface morphology, particle size, rate of release and calibration curve respectively. Results showed that urethane bonds were formed at 3300-3400cm-1 and 1650-1700 cm-1. SEM micrographs showed surface irregularities as a result of solvent evaporation. Particle sizes were higher for castor oil/HMDI rather than PCL/HMDI microbe ads and in both cases, particle size and Bromocresol purple die release increased with rising NCO/OH ratio.