PEG-grafted Hyperbranched Polyethyleneimine-Oxidized Single Walled Carbon Nanotube Complex (PEG-PEI-SWNT) for Sustained Delivery of Doxorubicin

To take advantages of single-walled carbon nanotubes (SWNTs) for cellular delivery of chemotherapeutic agents (e.g. doxorubicin) in order to decrease doxorubicin toxicity and increase its efficacy, we aimed to develop a novel approach to aqueous disperse and stabilize SWNTs through consequent steps of oxidation (oxSWNT) and PEG-PEI complexation (PEG-PEI-SWNT). Doxorubicin was loaded onto the modified SWNTs in alkalione pH with more considerable capacity ( 900 %) than those previously reported, due to complex formation with PEI proved by UV-visible spectroscopy. The loaded carrier was stable in physiologic simulated medium. Drug release was prolonged and dilution independent, but exhibited pH-dependent burst release that makes SWNTs as suitable in vivo drug carriers in acidic tumor milieu. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3492

Effect of pH on Solubilisation of Practically Insoluble Sorafenib by Classic and Stealth Polyamidoamine (PAMAM) Dendrimers and -cyclodextrin

This study is the first report of the solubilization of sorafenib (SFB), a water insoluble drug, by polyamidoamine (PAMAM) dendrimers and -cyclodextrin ( -CD). For this study whole generations (G4 and G5) of PAMAM dendrimers have been used. The aqueous solubility of sorafenib was measured in the presence of dendrimers and -cyclodextin at 30 ◦ C at pH 4, 7.4, and 10 using the Higuchi rotating bottle method. The amount of solubilized SFB was measured by HPLC-UV method. FTIR and UV-Vis spectroscopy were used to confirm complexation. From the phase solubility studies, it was found that PAMAM dendrimers increased SFB solubility most in pH 4. The maximum solubilizing effect was for G4 PAMAM dendrimers at pH 4 up to 36 folds. -CD did not or slightly increased the solubility of SFB. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3494

PEG conjugated citrate-capped magnetite nanoparticles for biomedical applications

We aim to develop polyethylene glycol decorated, citric acid capped magnetite nanoparticles (MNPs) with proper physicochemical characteristics including particle size distribution, morphology, magnetic property and stability in a biologic medium. MNP of about 10 nm were synthesized by a biocompatible chemical co-precipitation of Fe2+ and Fe3+ in an ammonia solution. A synthetic methodology has been developed to get a well dispersed and homogeneous aqueous suspension of MNPs. The naked MNPs are often insufficient for their stability, hydrophilicity and further functionalization. In order to overcome these limitations, citric acid was used to stabilize the magnetite particle suspension, which was anchored on the surface of freshly prepared MNPs by a direct addition method. Polyethylene glycol was covalently attached to the carboxylic moieties of citric acid anchored MNPs by carbodiimide chemistry. The microstructure and morphology of the nanoparticles were characterized by X-ray diffraction and transmission electron microscopy, and Fourier transform infrared spectroscopy. Also, the magnetic properties were investigated by vibrating sample magnetometry. It was found that the nanoparticles demonstrated superparamagnetic behavior