Sharif Digital Repository

Application of nanoparticles in targeted delivery and controlled drug release is recently highly attracted especially in cancer therapy. In this study with the aim of developing a novel drug vector based on metallic nanoparticles, gold nanoparticles with their unique characteristics were used to design a vector for targeted anti-cancer drug delivery to tumor. First, gold nanoparticles were chemically synthesized therough sodium citrate and sodium brohydrate reductions with average diameters of 22 and 11 nm, respectively. Then, the activated poly ethylene glycol (PEG) and activated folic acid were conjugated to the lysine-capped gold nanoparticles. Subsequently, the widely used anticancer... 

Poly (vinyl alcohol) (PVA) hydrogel is a biocompatible material, which has been widely applied in drug delivery applications. Microspheres, nanospheres, and other types of particle-based drug delivery vehicles have proven capacity for long-term release. There is growing interest to overcoming the inherent pharmacological limitations of hydrogels by formulating particulate systems into the hydrogel matrix to form new delivery platforms. We here describe a simple composite system based on poly (vinyl alcohol) (PVA) hydrogels containing entrapped drug-loaded poly (lactic acid) (PLA) microspheres for controlled delivery over extended period of time. Gamma-Irradiation and freeze-thawing was... 

Some chemotherapy drugs have unpleasant side effects and use them due to the instability and low solubility in blood flow is associated with problems and limitations.To solve these problems, controlled drug delivery systems have been proposed. In this process, the polymer increased solubility, stability and low toxicity and the active drug realease in a particular tissue or controlled speed. Therefore be less adverse side effects. Dextran is the one of biocompatible and water-soluble polysaccharides that due to its unique characteristics, widely used as carriers in drug delivery. Dextran molecules can bind to drugs and increased solubility, stability, and reduce their side effects.... 

With the rapid development of biotechnology, peptide and protein drugs are now playing an increasingly important role in therapeutics. Compared with chemical drugs, peptide and protein drugs have some limitations such as low stability and rapid deactivation. Biodegradable and biocompatible polymeric micro carriers have been shown to have a high potential for the delivery of peptides and proteins. Among these polymers, alginate has been widely investigated as a biomaterial. Alginates are natural polysaccharide polymers isolated from brown seaweed. Bovine serum albumin (BSA) loaded calcium alginate microspheres produced in this study by a modified w/o emulsification method. The influence of... 

In this work, pH sensitive supramolecular shuttles consisting of carbon nanotube-graft-pyrene (CNT-graft-PYR) and hyperbranched polyglycerol with β-cyclodextrin core (β-CD-graft-PG) were synthesized and characterized. Supramolecular systems (PG/CNT/S) were able to load and transport doxorubicin in aqueous solutions. While PG/CNT/S were soluble in phosphate buffer pH 7, they were divided to their individual moieties in pH 5 and therefore CNTs containing staked doxorubicin molecules were precipitated  

With the increasing development of the pharmaceutical industry and producing drugs with specific performance, its transfer into cells is also very important. Cell membranes are effectively impermeable to hydrophilic compounds unless the permeation is facilitated by dedicated transport systems. This means that many hydrophilic compounds, including many promising drug candidates, fail to reach their intracellular target because they cannot spontaneously cross lipid membranes. As a consequence, there is much interest in finding ways to facilitate the transport of molecules across cell membranes. Cell-penetrating peptides (CPPs) in particular have shown much promise as potential delivery agents... 

Particle retention and clearance is a major concern in the treatment of pulmonary diseases. Inhaled materials into the nasal and lung airways include gases/vapors, liquid droplets and soluble/insoluble particulate matter which can be toxic or therapeutic (or both). For example, nanoparticles (NPs), as part of nanomedicine, are now being used as drug carriers for passive and active targeting of solid tumors and inflamed tissue. However, natural and especially manmade NPs can also be harmful, such as carbon nanotubes (CNTs), asbestos fibers and ambient toxic pollutants, based on epidemiological and pathological studies of occupational and environmental exposures. In fact, ultrafine particles... 

Age-related macular degeneration (AMD) is the most common cause of vision loss in those aged over 50. There are two main types of AMD, Wet and Dry form. Wet AMD is more severe though more treatable. There are three conventional treatments for AMD including laser therapy, surgery and intravitreal injection of anti-VEGF into the eye. Delivery of drugs to the posterior segment of the eye is still challenging and several implants and devices are currently under investigation for their ability to stimulate the retina, producing visual percepts. The application of intravitreal bevacizumab (Avastin) has expanded tremendously from the time of its introduction into ophthalmic care since 3 years ago.... 

Transdermal drug delivery systems are products which are known to have ability to pass drugs through the skin and into the blood, so medicine effects appear as a result. During the past two decades, many scientists interested in drug delivery through the skin. Constant blood plasma level and avoiding first-pass metabolism are advantages of this system compared to oral and intravenous systems. The biggest problem in the development of these systems, is impermeability of Stratum corneum, the outermost layer of the epidermis. In this study, design and evaluation of in vitro transdermal drug delivery system for granisetron serve as treatment of nausea and vomiting was performed. For this... 

Age-related macular degeneration (AMD) is the most common cause of vision loss in those aged over 50. There are two main types of AMD, Wet and Dry form. Wet AMD is more severe though more treatable. There are three conventional treatments for AMD including laser therapy, surgery and intravitreal injection of anti-VEGF into the eye. Delivery of drugs to the posterior segment of the eye is still challenging and several implants and devices are currently under investigation for their ability to stimulate the retina, producing visual percepts. The application of intravitreal bevacizumab (Avastin) has expanded tremendously from the time of its introduction into ophthalmic care since 3 years ago.... 

Drug-eluting bone implant coatings is a new era that has gained a lot of attention in recent years. In this matter, drug is loaded in the coating and local and targeted release of the drug results in preventing the side effects of implantation and increasing the healing process of the patient. The aim of this project was to synthesis the antibiotic eluting chitosan-based composite using electrophoretic deposition for bone implant coating. By using electrophoretic deposition chitosan and chitosan-bioglass composite coatings were synthesized. Then the probability of loading of drug into coating by using electrophoretic deposition was evaluated and by using this process chitosan and... 

In this project, Fe3O4 nanoparticles were synthesized and coated with different polymeric materials for drug delivery application. For this purpose, water dispersible oleic acid(OA)- pluronic block copolymer coated magnetite iron oxide nanoparticles were synthesized that can be loaded with proper doses of cephalexin. Our data indicated that formulation of iron oxide nanoparticles was developed by optimizing the amount of oleic acid required to coat iron oxide nanoparticles and then by optimizing the amount of pluronic required to form an aqueous dispersion of oleic acid coated nanoparticles. Synthesis of magnetite nanoparticles was done by the addition of a strong base (NH4OH) to ferrous... 

Since the development of various anti-cancer drugs, numerous attempts have been made to decrease their off-target adverse effects anhance their efficiency.Among these efforts developing novel drug delivery systems have been demonstrate promising potentials and lots of carriers have reached the market and clinical phases.Although plentiful researches on different drug carriers, lots of problems in drug loading, release and final efficiency are yet remaind.In recent decade, graphene oxide and graphene aerogel have been attracted remarkable intrest as drug carriers, due to their biodegradable and biocompatible characteristics.Accordingly, in this study graphene aerogel have been synthesized... 

In recent years along with time and cost intensive process of developing new and better drugs for diseases like cancer, scientists and researchers are attempting to develop novel drug delivery systems for already existing drugs.The purpose of these novel drug delivery systems such as nanogels is controlling drug release rate as well as delivery to a specific target tissue in order to reduce side effects. One of the most commonly used drugs for cancer treatment is Doxorubicin HCl, commercially known as Adricin. In this project biodegradable and biocompatible polymers PLA and PEG were used to synthesize nanocarriers for Adricin. These nanocarriers were then dispersed in an agar hydrogel. The... 

Due to the increasing need of use of drugs and insufficient efficiency of conventional methods, drug delivery systems has gathered a lot of interests. There are different systems existing for controlled drug delivery, among which is implementation of hydrogel microparticles (microgels) as carriers with high potential. The most important factor in these systems is size distribution of drug-carrying microgels and a narrow size distribution leads to a controlled and suitable release. Due to unique characteristics of microfluidic systems, significant focus has been placed on them nowadays for production of microgels with suitable morphology and narrow size distribution. Therefore, in this study... 

Breast cancer is the fifth cause of death from cancer and one of the most common fatal cancers in women. The commonly drugs used to treat cancer often destroy healthy tissues and cells and cause common side effects. It is also necessary to consume a large amount of the drug to achieve a particular effect. One of the applications of nanotechnology is drug delivery. Niosomes are one of the newest drug delivery systems that are nowadays much more widely considered due to better penetration and controlled release. One of the most effective medicines for treating breast cancer is statins. These drugs are a group of lipids lowering drugs that lower the synthesis of cholesterol by inhibiting the... 

With the fast progress of nanotechnology, targeted drug delivery systems have been widely developed due to decreasing in the drug dosage and subsequently side effects of them into body. These smart systems are able to response to the surroundings stimuli. External stimuli in comparison with internal stimuli are more controllable, and can release drug at the targeted side in the desirable times. In the recent studies, there has been an increasing interest in the usage of LASER as an external stimulus due to high precision, short time response, and suitable practical function. For cancer therapy, several studies have been done by focusing on the hyperthermia effects of gold nanoparticles. In... 

In this study a mathematical model for intravitreal injection and depositing controlled release systems in the eye to treat posterior segment deseases is developed. The effects of important parameters that play a critical role in drug distribution are also studied.
Geometrical model is constructed using COMSOL software and governing equations for a 3-D model of drug distribution are solved by finite element method. The geometry is based on the exact dimensions of human eye and retina, choroid and sclera are considered separately. Choroidal losses to the circulatory system and active transport by the retinal pigment epithelium are incorporated as well. Moreover, two types of implant... 

In recent decades, due to the significant growth of implants’ application and considering the infection of the implants as the most momentous factor in implantation failure, study on the controlled drug release and other biologically active agents in modern drug delivery systems has attracted many kinds of research throughout the world and efforts are being made to use regulated drug delivery systems for implantation which is also the purpose of this current scientific work.To achieve this, the anodizing process was used to fabricate titanium oxide nanotubes (TNTs) to increase the absorption capacity of the drug in the implants and these TNTs were formed regularly and uniformly in an organic... 

Since 1992, many different methods have been introduced and developed according to the type of application of catalytic Janu micromotors in various fields. In this study, the method of particles masking was used to construct magnesium based catalytic micromotors. The stabilizing of magnesium microparticles was carried out in 3 methods, resuspending with PVP, paraffin and static electricity generation on Slides. Finally, all three methods quality was investigated and paraffin stabilizing was best selected for the stability of particles on the slides. After making the micromotors, the effect of several factors, including the amount of sputtering time, PBS medium with different Ph of (7.4 , 6.4...