Search tips
Search criteria

Results 1-10 (10)

Clipboard (0)

Select a Filter Below

Year of Publication
Document Types
1.  Liposome: classification, preparation, and applications 
Nanoscale Research Letters  2013;8(1):102.
Liposomes, sphere-shaped vesicles consisting of one or more phospholipid bilayers, were first described in the mid-60s. Today, they are a very useful reproduction, reagent, and tool in various scientific disciplines, including mathematics and theoretical physics, biophysics, chemistry, colloid science, biochemistry, and biology. Since then, liposomes have made their way to the market. Among several talented new drug delivery systems, liposomes characterize an advanced technology to deliver active molecules to the site of action, and at present, several formulations are in clinical use. Research on liposome technology has progressed from conventional vesicles to ‘second-generation liposomes’, in which long-circulating liposomes are obtained by modulating the lipid composition, size, and charge of the vesicle. Liposomes with modified surfaces have also been developed using several molecules, such as glycolipids or sialic acid. This paper summarizes exclusively scalable techniques and focuses on strengths, respectively, limitations in respect to industrial applicability and regulatory requirements concerning liposomal drug formulations based on FDA and EMEA documents.
PMCID: PMC3599573  PMID: 23432972
Liposomes; Glycolipids; Drug formulations; Drug delivery systems
2.  Comparison of Cytotoxic Activity of L778123 as a Farnesyltranferase Inhibitor and Doxorubicin against A549 and HT-29 Cell Lines 
Purpose: Farnesyltransferase (FTase) is a zinc-dependent enzyme that adds a farnesyl group to the Ras proteins. L778, 123 is a potent peptidomimetic imidazole-containing FTase inhibitor. Methods: L778123 was synthesized according to known methods and evaluated alone and in combination with doxorubicin against A549 (adenocarcinomic human alveolar basal epithelial cells) and HT29 (human colonic adenocarcinoma) cell lines by MTT assay. Results: L778123 showed weak cytotoxic activity with IC50 of 100 and 125 for A549 and HT-29 cell lines, respectively. The combination of doxorubicin and L778123 can decrease IC50 of doxorubicin in both cell lines significantly. Conclusion: It can be concluded that L778, 123 can be a good agent for combination therapy.
PMCID: PMC3846042  PMID: 24312815
Farnesyltransferase inhibitor; MTT assay; Combination therapy; L-778123
3.  Synthesis, characterization and in vitro studies of doxorubicin-loaded magnetic nanoparticles grafted to smart copolymers on A549 lung cancer cell line 
The aim of present study was to develop the novel methods for chemical and physical modification of superparamagnetic iron oxide nanoparticles (SPIONs) with polymers via covalent bonding entrapment. These modified SPIONs were used for encapsulation of anticancer drug doxorubicin.
At first approach silane–grafted magnetic nanoparticles was prepared and used as a template for polymerization of the N-isopropylacrylamide (NIPAAm) and methacrylic acid (MAA) via radical polymerization. This temperature/pH-sensitive copolymer was used for preparation of DOX–loaded magnetic nanocomposites. At second approach Vinyltriethoxysilane-grafted magnetic nanoparticles were used as a template to polymerize PNIPAAm-MAA in 1, 4 dioxan and methylene-bis-acrylamide (BIS) was used as a cross-linking agent. Chemical composition and magnetic properties of Dox–loaded magnetic hydrogel nanocomposites were analyzed by FT-IR, XRD, and VSM.
The results demonstrate the feasibility of drug encapsulation of the magnetic nanoparticles with NIPAAm–MAA copolymer via covalent bonding. The key factors for the successful prepardtion of magnetic nanocomposites were the structure of copolymer (linear or cross-linked), concentration of copolymer and concentration of drug. The influence of pH and temperature on the release profile of doxorubicin was examined. The in vitro cytotoxicity test (MTT assay) of both magnetic DOx–loaded nanoparticles was examined. The in vitro tests showed that these systems are no toxicity and are biocompatible.
IC50 of DOx–loaded Fe3O4 nanoparticles on A549 lung cancer cell line showed that systems could be useful in treatment of lung cancer.
PMCID: PMC3605180  PMID: 23244711
Superparamagnetic iron oxide nanoparticles (SPIONs); Drug loading efficiency; Radical polymerization; N-Isopropylacrylamide-methyl metacrylc acid (NIPAAm-MAA)
4.  Quantum dots: synthesis, bioapplications, and toxicity 
Nanoscale Research Letters  2012;7(1):480.
This review introduces quantum dots (QDs) and explores their properties, synthesis, applications, delivery systems in biology, and their toxicity. QDs are one of the first nanotechnologies to be integrated with the biological sciences and are widely anticipated to eventually find application in a number of commercial consumer and clinical products. They exhibit unique luminescence characteristics and electronic properties such as wide and continuous absorption spectra, narrow emission spectra, and high light stability. The application of QDs, as a new technology for biosystems, has been typically studied on mammalian cells. Due to the small structures of QDs, some physical properties such as optical and electron transport characteristics are quite different from those of the bulk materials.
PMCID: PMC3463453  PMID: 22929008
QD delivery systems; Toxicity; Emission spectra; Luminescence characteristics
5.  Magnetic nanoparticles: preparation, physical properties, and applications in biomedicine 
Nanoscale Research Letters  2012;7(1):144.
Finally, we have addressed some relevant findings on the importance of having well-defined synthetic strategies developed for the generation of MNPs, with a focus on particle formation mechanism and recent modifications made on the preparation of monodisperse samples of relatively large quantities not only with similar physical features, but also with similar crystallochemical characteristics. Then, different methodologies for the functionalization of the prepared MNPs together with the characterization techniques are explained. Theorical views on the magnetism of nanoparticles are considered.
PMCID: PMC3312841  PMID: 22348683
magnetic nanoparticles; synthetic routes; biomedical applications; functionalization techniques; characterization
6.  Synthesis, characterization, and in vitro evaluation of novel polymer-coated magnetic nanoparticles for controlled delivery of doxorubicin 
Poly (N-isopropylacrylamide-methyl methacrylic acid, PNIPAAm-MAA)-grafted magnetic nanoparticles were synthesized using silane-coated magnetic nanoparticles as a template for radical polymerization of N-isopropylacrylamide and methacrylic acid. Properties of these nanoparticles, such as size, drug-loading efficiency, and drug release kinetics, were evaluated in vitro for targeted and controlled drug delivery. The resulting nanoparticles had a diameter of 100 nm and a doxorubicin-loading efficiency of 75%, significantly higher doxorubicin release at 40°C compared with 37°C, and pH 5.8 compared with pH 7.4, demonstrating their temperature and pH sensitivity, respectively. In addition, the particles were characterized by X-ray powder diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. In vitro cytotoxicity testing showed that the PNIPAAm-MAA-coated magnetic nanoparticles had no cytotoxicity and were biocompatible, indicating their potential for biomedical application.
PMCID: PMC3781717  PMID: 24198493
magnetic nanoparticles; drug loading; doxorubicin release; biocompatibility
7.  Preparation and in vitro evaluation of doxorubicin-loaded Fe3O4 magnetic nanoparticles modified with biocompatible copolymers 
Superparamagnetic iron oxide nanoparticles are attractive materials that have been widely used in medicine for drug delivery, diagnostic imaging, and therapeutic applications. In our study, superparamagnetic iron oxide nanoparticles and the anticancer drug, doxorubicin hydrochloride, were encapsulated into poly (D, L-lactic-co-glycolic acid) poly (ethylene glycol) (PLGA-PEG) nanoparticles for local treatment. The magnetic properties conferred by superparamagnetic iron oxide nanoparticles could help to maintain the nanoparticles in the joint with an external magnet.
A series of PLGA:PEG triblock copolymers were synthesized by ring-opening polymerization of D, L-lactide and glycolide with different molecular weights of polyethylene glycol (PEG2000, PEG3000, and PEG4000) as an initiator. The bulk properties of these copolymers were characterized using 1H nuclear magnetic resonance spectroscopy, gel permeation chromatography, Fourier transform infrared spectroscopy, and differential scanning calorimetry. In addition, the resulting particles were characterized by x-ray powder diffraction, scanning electron microscopy, and vibrating sample magnetometry.
The doxorubicin encapsulation amount was reduced for PLGA:PEG2000 and PLGA:PEG3000 triblock copolymers, but increased to a great extent for PLGA:PEG4000 triblock copolymer. This is due to the increased water uptake capacity of the blended triblock copolymer, which encapsulated more doxorubicin molecules into a swollen copolymer matrix. The drug encapsulation efficiency achieved for Fe3O4 magnetic nanoparticles modified with PLGA:PEG2000, PLGA:PEG3000, and PLGA:PEG4000 copolymers was 69.5%, 73%, and 78%, respectively, and the release kinetics were controlled. The in vitro cytotoxicity test showed that the Fe3O4-PLGA:PEG4000 magnetic nanoparticles had no cytotoxicity and were biocompatible.
There is potential for use of these nanoparticles for biomedical application. Future work includes in vivo investigation of the targeting capability and effectiveness of these nanoparticles in the treatment of lung cancer.
PMCID: PMC3273983  PMID: 22334781
superparamagnetic iron oxide nanoparticles; triblock copolymer; doxorubicin encapsulation; water uptake; drug encapsulation efficiency
8.  Novel Aldehyde-Terminated Dendrimers; Synthesis and Cytotoxicity Assay 
BioImpacts : BI  2012;2(2):97-103.
Polyamidoamine (PAMAM) dendrimers are a unique family of dendritic polymers with numerous pharmaceutical and biomedical applications. One major problem with these polymers is their cytotoxicity. The purpose of this study was to synthesize novel dendrimers with aldehyde terminal groups and compare their cytotoxicity with that of dendri¬mers containing amine-terminated groups.
G1(first generation) and G2 (second generation) dendrimers with amine-terminated groups were synthesized by divergent method and then the amine-terminated groups were converted to the aldehyde groups using surface modification of the functional group inversion (FGI) method. The cytotoxicity of the novel G1 and G2 polyamidoaldehyde (PAMAL) dendrimers together with that of G1 and G2 PAMAM-NH2 dendrimers was investigated by MTT assay using MCF-7 cell line.
The results showed that cytotoxicity of dendrimers with aldehyde-terminated groups is much lower than that of G1 and G2 PAMAM-NH2 dendri¬mers.
Dendrimers with aldehyde-terminated groups could be used as novel and convenient carriers for drug delivery with low cytotoxic effect compared with the amine-terminated dendrimers. The results revealed that the same generations of the dendri¬mers with aldehyde-terminated groups are far less toxic than the corresponding amine-terminated dendrimers.
PMCID: PMC3648925  PMID: 23678447
PAMAM; Dendrimers; Cytotoxicity; FGI Method; MTT Assay
9.  Preparation and Characterization of a Novel Smart Polymeric Hydrogel for Drug Delivery of Insulin  
BioImpacts : BI  2011;1(2):135-143.
Over the past years, temperature and pH-sensitive hydrogels was developed as suitable carriers for drug delivery. In this study temperature and pH-sensitive hydrogels was designed for an oral insulin delivery modeling.
NIPAAm-MAA -HEM copolymers were synthesized by radical chain reaction with 86:4:10 (5% w/v) ratios respectively. Reaction was carried out in 1,4-Dioxane under Nitrogen gas-flow. The copolymers were characterized with FT-IR, 1H-NMR and DSC. Copolymers were loaded with regular insulin by modified double emulsion method with ratio of 1:10. Release study carried out in two different pH (pH=2 and 7.4 for stomach and intestine simulation respectively) at 37ºC. For each pH, a 5 mL suspension of the insulin containing hydrogel was taken in to a cellulose acetate dialysis membrane, and the dialysis membrane was allowed to float in a beaker containing 15 mL of buffer solution. The beakers were placed in a shaker incubator maintained at 37ºC. Phosphate buffer (0.1 M, pH 3)/ acetonitrile (60/40) was used as the mobile phase in HPLC assay.
Yield of reaction was 86% with an optimum Lower Critical Solution Temperature point (30ºC). In-vitro studies showed a control release behavior via pH changes which the amount of insulin releases was 80% and 20% at pH=2 and 7.4 respectively.
Results showed that by optimizing polymerization and loading method we could achieve a suitable nano system for oral delivery of insulin.
PMCID: PMC3648951  PMID: 23678418
Oral Drug Delivery; NIPAAm; Hydrogel; Insulin
10.  Adriamycin release from poly(lactide-co-glycolide)-polyethylene glycol nanoparticles: synthesis, and in vitro characterization 
The preparation, properties, and application in adriamycin delivery of biocompatible and biodegradable poly(lactide-co-glycolide)-polyethylene glycol (PLGA-PEG) nanoparticles are discussed. PLGA-PEG copolymers were synthesized by ring opening polymerization of the dl-lactide and glycolide in the presence of PEG1000.1H-NMR and FT-IR spectrum were consistent with the structure of PLGA-PEG copolymers. The adriamycin-loaded nanoparticles could be prepared using a precipitation-solvent evaporation technique. The nanoparticles have been produced by a precipitation-solvent evaporation technique. The physical characteristics and drug loading efficiency of the PLGA-PEG nanoparticles were influenced by the composition of the PLGA-PEG copolymers used to prepare the nanoparticles. Particle sizes were between 65 and 100 nm for different compositions of PLGA-PEG copolymers. PLGA-PEG nanoparticles prepared from copolymers having relatively high PLGA/PEG ratios were smaller. Entrapment efficiency was 25%–33%. Adriamycin release from the nanoparticles at pH 7.4 showed an initial burst release and then sustained release phase. These results showed that PLGA-PEG nanoparticles could be an effective carrier for cancer therapy.
PMCID: PMC2676638  PMID: 17722284
adriamycin; PLGA-PEG copolymers; cancer therapy; drug delivery systems

Results 1-10 (10)