Gemcitabine-loaded chitosan microspheres. Characterization and biological in vitro evaluation

Abstract

This study investigates the potential of chitosan microspheres as delivery systems for the anticancer drug gemcitabine. The microspheres were obtained by spray-drying chitosan-gemcitabine solutions containing different amounts of the polyanion dextran sulphate. Morphological characterization by SEM and FIB analyses showed the presence of porous spherical particles having sizes ranging from about 1 to 5 μm. Dextran sulphate improves the technological parameters of the systems by producing very high encapsulation efficiency (about 96%, w/w) and by influencing the in vitro release of gemcitabine. The immediate drug release observed in the system prepared without dextrane sulphate (complete drug release within 30 min) was somewhat reduced by the polyanion (immediate release of 70% (w/w) of the encapsulated drug within 30 min, and subsequent continued release of the remaining 30% of the drug for over 4 days). The anti-tumoral efficacy of the various formulations was tested in vitro on human lung cancer cells (A549) comparing the effects with those of the free drug or drug/dextran sulfate complex. The carriers improved the cytotoxic activity of the drug, particularly the formulation containing the lowest amount of dextran sulphate after 72 h incubation.

Physicochemical features and transfection properties of chitosan/poloxamer 188/poly(D,L-lactide-co-glycolide) nanoplexes

“…Unfortunately, PLGA has a negative charge, which limits its interaction with DNA/RNA, so cationic compounds have been combined with this polymer in order to condense genetic material efficiently. 17,18 For example, chitosan, a polysaccharide used widely in the pharmaceutical field because of its biocompatibility, biodegradability, safety, and mucoadhesive properties, 19,20 has been used in combination with PLGA in order to increase transfection efficiency. 21,22 In 2007, Nafee et al investigated the variation in physicochemical parameters of PLGA/high molecular weight chitosan nanoparticles (produced by the emulsion-diffusionevaporation technique) as a function of the proportions of compounds contained therein.…”

Overcoming tumor cell chemoresistance using nanoparticles: lysosomes are beneficial for (stearoyl) gemcitabine-incorporated solid lipid nanoparticles

“…Nanomedicines have unique advantages in overcoming tumor cell resistance to gemcitabine, and various types of gemcitabine nanomedicine formulations, such as micelles, 156 liposomes, 157 supramolecular vesicular aggregates, and nanovesicles, [158][159][160] have been shown to circumvent gemcitabine resistance. The general mechanisms by which gemcitabine nanomedicines overcome gemcitabine chemoresistance are discussed below.…”

Rutin-loaded chitosan microspheres: Characterization and evaluation of the anti-inflammatory activity

“…Morphological characterization and the surface charges of the microsystems were evaluated through scanning electron microscopy (SEM) and photocorrelation spectroscopy, respectively (Ventura et al, 2011).…”