Preparation and characterization of polymeric nanoparticles surface modified with chitosan for target treatment of colorectal cancer.

5-Fluorouracil (5-FU) loaded chitosan (C) coated polylactic-co-glycolic acid (PLGA) nanoparticles [NPs] (C-5-FU PLGA NPs) and polycaprolactone [PCL] (C-5-FU PCL NPs) were employed as the carriers for cancer treatment. The prepared NPs showed the spherical shape of NPs with the particle size in the range of 188.1-302.

Enhanced Ehrlich tumor inhibition using DOX-NP and gold nanoparticles loaded liposomes.

Treatment with doxorubicin (DOX) is a common treatment for different types of cancer. DOX-NP is one of a well established marketed liposomal formulation for DOX. It has advantages over free DOX in reducing the cardiac toxicity and increasing the efficacy.

Ehrlich tumor inhibition using doxorubicin containing liposomes.

Ehrlich tumors were grown in female balb mice by subcutaneous injection of Ehrlich ascites carcinoma cells. Mice bearing Ehrlich tumor were injected with saline, DOX in solution or DOX encapsulated within liposomes prepared from DMPC/CHOL/DPPG/PEG-PE (100:100:60:4) in molar ratio. Cytotoxicity assay showed that the IC50 of liposomes containing DOX was greater than that DOX only.

Interaction of doxorubicin and dipalmitoylphosphatidylcholine liposomes.

The interaction between doxorubicin (DOX), an anthracycline antibiotic frequently used in chemotherapy, and zwitterionic dipalmitoylphosphatidylcholine (DPPC) was investigated using Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and rheological measurements. FTIR results showed that DOX shifted the wavenumber of the PO(2)(-) band for pure DPPC to a higher wavenumber. This may have been because of the strong interactions between the NH(3)(+) group in DOX and the phosphate (PO(2)(-)) group in the polar head of DPPC.

Rheological and dielectric properties of different gold nanoparticle sizes.

Background: Gold nanoparticles (GNPs) have found themselves useful for diagnostic, drug delivery and biomedicine applications, but one of the important concerns is about their safety in clinical applications. Nanoparticle size has been shown to be an extremely important parameter affecting the nanoparticle uptake and cellular internalization. The rheological properties assume to be very important as it affects the pressure drop and hence the pumping power when nano-fluids are circulated in a closed loop.

Liver uptake of gold nanoparticles after intraperitoneal administration in vivo: a fluorescence study.

Background: One particularly exciting field of research involves the use of gold nanoparticles (GNPs) in the detection and treatment of cancer cells in the liver. The detection and treatment of cancer is an area in which the light absorption and emission characteristics of GNPs have become useful. Currently, there are no data available regarding the fluorescence spectra or in vivo accumulation of nanoparticles (NPs) in rat liver after repeated administration.

Biophysical characterization of gold nanoparticles-loaded liposomes.

Gold nanoparticles were prepared and loaded into the bilayer of dipalmitoylphosphatidylcholine (DPPC) liposomes, named as gold-loaded liposomes. Biophysical characterization of gold-loaded liposomes was studied by transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy as well as turbidity and rheological measurements. FTIR measurements showed that gold nanoparticles made significant changes in the frequency of the CH(2) stretching bands, revealing that gold nanoparticles increased the number of gauche conformers and create a conformational change within the acyl chains of phospholipids.

The influence of low power microwave on the properties of DPPC vesicles.

The effect of microwave exposure on liposome at non-thermal level are studied. Dipalmitoyl phosphatidylcholine (DPPC) liposomes were exposed to 950 MHz at power densities of 2.5 mW/cm(2), which is equivalent to specific absorption rate (SAR) of 0.

Biophysical studies on chitosan-coated liposomes.

Liposomes have been used as delivery vehicles for stabilizing drugs, overcoming barriers to cellular and tissue uptake, and for directing their contents toward specific sites in vivo. Chitosan is a biological macromolecule derived from crustacean shells and has several emerging applications in drug development, obesity control, and tissue engineering. In the present work, the interaction between chitosan and dipalmitoyl phosphatidylcholine (DPPC) liposomes was studied by transmission electron microscopy (TEM), zeta potential, solubilization using the nonionic detergent octylglucoside (OG), as well as Fourier transform infrared (FTIR) spectroscopy and viscosity measurements.

Efficiency of cytoplasmic delivery by non-cationic liposomes to cells in vitro: a confocal laser scanning microscopy study.

It is necessary to understand liposomal uptake mechanisms and intracellular distribution in order to design more efficient gene (drug) carrier systems. Until now, a few studies have been carried out using confocal laser scanning microscopy (CLSM) to investigate the cellular uptake and transfection mediated with liposomes. So, by CLSM, we demonstrated that artificial virus-like envelope (AVE) vesicles labeled with rhodamine-PE (Rh-PE), carbocyanine (DiI) and carboxyfluorescein (CF) were investigated into the cytoplasm of two human cell lines, Mewo (human melanoma cell line) and HepG2 (human hepatoma cell line) cells grown in DMEM medium supplemented with different percentages (0%, 30%, and 100%) fetal calf serum (FCS).

Biophysical studies on collagen-lipid interaction.

The potential use of liposomes as a delivery system is still limited by the poor understanding of the interaction mechanisms of liposomes underlying with biological media. Interaction between liposomes and protein is important for the structure and function of cells. In the present work, the interaction between collagen and dipalmitoyl phosphatidylcholine (DPPC) liposomes was studied by solubilization using a nonionic detergent, octylglucoside (OG), as well as a monolayer technique.

Efficient gene delivery with serum into human cancer cells using targeted anionic liposomes.

Success of human gene therapy depends upon the development of delivery vehicles or vectors, which can selectively deliver therapeutic genes to target cells with efficiency and safety. Previous studies have shown an efficient, systemic trans-gene expression in many cell lines (in vitro) by using an anionic liposomal vector, based on the composition of retroviral envelopes (artificial viral envelopes, AVEs). The AVE-liposomes and their complexes with plasmid (DNA) were characterized according to zeta potential measurements and transmission electron microscopy (TEM).