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1.  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.
doi:10.1186/1556-276X-7-480
PMCID: PMC3463453  PMID: 22929008
QD delivery systems; Toxicity; Emission spectra; Luminescence characteristics
2.  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.
doi:10.2147/NSA.S24328
PMCID: PMC3781717  PMID: 24198493
magnetic nanoparticles; drug loading; doxorubicin release; biocompatibility
3.  Preparation and in vitro evaluation of doxorubicin-loaded Fe3O4 magnetic nanoparticles modified with biocompatible copolymers 
Background
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.
Methods
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.
Results
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.
Conclusion
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.
doi:10.2147/IJN.S24326
PMCID: PMC3273983  PMID: 22334781
superparamagnetic iron oxide nanoparticles; triblock copolymer; doxorubicin encapsulation; water uptake; drug encapsulation efficiency
4.  Sensitivity and specificity of median nerve ultrasonography in diagnosis of carpal tunnel syndrome 
Background
Although controversial, recent studies have demonstrated advantages of sonographic techniques in the diagnosis of carpal tunnel syndrome (CTS). The purpose of this study was to assess the utility of median nerve ultrasonography in the diagnosis of CTS in Iranian patients.
Methods
Ninety patents with clinically suspected CTS were studied. Based on gold standard electromyography/nerve conduction velocity studies, wrists with CTS were divided into three groups on the basis of severity of CTS, ie, mild, moderate, and severe. In addition, both sides of the wrist were examined using sonography. Transverse images of the median nerve were obtained and median nerve cross-section areas were measured at three levels, ie, immediately proximal to the carpal tunnel inlet, at the carpal tunnel inlet, and at the carpal tunnel outlet. Furthermore, flexor retinaculum thickness was evaluated.
Results
The mean age of the studied patients was 48.52 ± 12.17 years. Median values of the median nerve cross-section at the carpal tunnel inlet, carpal tunnel outlet, and proximal carpal tunnel significantly differed between the wrists with and without CTS (P < 0.05). Comparisons between the CTS groups (mild, moderate, and severe) and non-CTS wrists demonstrated that the median cross-sections of median nerve at the carpal tunnel inlet, carpal tunnel outlet, and inlet proximal carpal tunnel were significantly greater in the severe CTS group than in the other three groups (P < 0.05). The results showed that the median nerve cross-section at the three levels of carpal tunnel could only fairly differentiate severe CTS from other cases.
Conclusion
The present study demonstrated that median nerve ultrasonography cannot replace the gold standard test (nerve conduction velocity) for the diagnosis of CTS because of low overall sensitivity and specificity, although it might provide useful information in some patients.
doi:10.2147/IJGM.S17785
PMCID: PMC3273372  PMID: 22319247
median nerve; ultrasonography; carpal tunnel syndrome; diagnosis

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