Loading of beclomethasone in liposomes and hyalurosomes improved with mucin as effective approach to counteract the oxidative stress generated by cigarette smoke extract

In this work beclomethasone dipropionate was loaded into liposomes and hyalurosomes modified with mucin to improve the ability of the payload to counteract the oxidative stress and involved damages caused by cigarette smoke in the airway. The vesicles were prepared by dispersing all components in the appropriate vehicle and sonicating them, thus avoiding the use of organic solvents. Unilamellar and bilamellar vesicles small in size (~117 nm), homogeneously dispersed (polydispersity index lower than 0.22) and negatively charged (~−11 mV), were obtained. Moreover, these vesicle dispersions were stable for five months at room temperature (~25◦C). In vitro studies performed using the Next Generation Impactor confirmed the suitability of the formulations to be nebulized as they were capable of reaching the last stages of the impactor that mimic the deeper airways, thus improving the deposition of beclomethasone in the target site. Further, biocompatibility studies performed by using 16HBE bronchial epithelial cells confirmed the high biocompatibility and safety of all the vesicles. Among the tested formulations, only mucin-hyalurosomes were capable of effectively counteracting the production of reactive oxygen species (ROS) induced by cigarette smoke extract, suggesting that this formulation may represent a promising tool to reduce the damaging effects of cigarette smoke in the lung tissues, thus reducing the pathogenesis of cigarette smoke-associated diseases such as chronic obstructive pulmonary disease, emphysema, and cancer

Formulation and evaluation of cefuroxim loaded submicron particles for ophthalmic delivery

cited By 8International audienceChitosan gelatin particles could be the ideal candidate for intraocular drug delivery due to their desirable properties. Double crosslinking in double emulsion has been used as an original and reliable method for particles preparation and their morphology has been optimized considering the main synthesis parameters such as polymers ratio, crosslinker amount, stirring speed, tensioactive amount and ionic crosslinking time, respectively. The particles have been analyzed for their physical-chemical properties (swelling degree, drug loading and release capacity, surface characteristics, etc.), the enzymatic degradation properties along with in vivo ocular investigations (ocular biodistribution, in vivo drug release). In the present study cefuroxim was used as a model drug, which is generally used in the prophylaxis of postoperative endophthalmitis following cataract surgery after intraocular administration. The present study proved that the dimensions and the physical-chemical properties of the particles can be modulated (by varying the preparation parameters) to facilitate the administration, the biodistribution and the drug release in the specific segment of the eye. This experimental study demonstrated also the ability of fluorescent nanoparticles to penetrate ocular tissues close to the administration site (intravitreal injection) and especially their tendency to migrate deep in the retina at time intervals of 72 h. © 2015 Published by Elsevier B.V

Drug Release Kinetics from Polymer Matrix through Fractal Approximation of Motion

The present paper analyzes the process of drug release from polymer matrix. This process has been considered as fractal polymer process. Since complexity of physical processes is replaced by fractality, the paper studies the process through fractal approach. In drug dynamics, fractal “diffusion” equation can be obtained through fractal approximation of motion. All experimental release curves have been best demonstrated by Weibull relation (which was, in its turn, also demonstrated). Weibull parameters are related to the fractal dimension of drug release kinetics from a polymer matrix. Such a dimension can characterize and measure the complexity of the system. In the above-mentioned context, some experimental results of our researchers are presented and analyzed by comparing them with Peppas relation, a basic law in the description of drug release kinetics. Consequently, experimental data for Weibull relation are better correlated with certain resulting factors. At the same time, some conclusions regarding the phenomena involved in the process are considered as being based on the approach

TARGETING HIGH DOSE NIFEDIPINE-INDUCED HIPERTROPHY IN TISSUES WITH HYDROCORTISONE-LOADED NANOCARRIERS

We aim to study organ penetrability and anti-inflammatory effect of Hydrocortisone-loaded nanoparticles (HC-nano) after inducing hypertrophy with previous very-high dose medium-term Nifedipine administration. Materials and methods: Experiment was conducted in two phases on 60 adult, healthy Wistar rats, randomly divided initially in two groups (Phase 1), respecting 1:1 ratio between males and non-pregnant females, within each group. Group A1 (control) included 20 rats (10M/10F) and received no medication. Group B1 included 40 rats (20M/20F) and received oral Nifedipine 100 mg/kg body weight daily (approximately 100x therapeutic human dose), for 4 weeks. When Phase 1 ended, 8 rats did not survive in Group B1, and 40% (approximated to nearest integer) of rats of each sex, within each group were sacrificed, organs were harvested and analyzed microscopically. The rest of living rats entered Phase 2: Group A2 (control) remained with 12 rats (6M/6F) continuing with no medication; Group B2 counted 18 rats (10M/8F) that were given oral HC-nano 2 mg/kg body weight daily (therapeutic dose), for another 4 weeks. After Phase 2 completion, all animals were sacrificed, and tissues were microscopically analyzed. Results: Nifedipine induced statistically significant hypertrophy in the studied organs, with impressive results in gingiva (capillaries, p0.05). Recorded hypergrowth did not differ significantly between sexes in Group B1, regardless of the organ (p>0.05), but 3 times more females died within Phase 1, due to very-high dose Nifedipine toxicity. After Phase 2, hypertrophy reduction was statistically significant in Group B2 (Hydrocortisone) compared with Group B1 (Nifedipine), in gums, heart (muscle fiber diameter) and kidneys (p0.05). Conclusions: Very-high dose medium-term Nifedipine induces similar hypertrophic effects like chronic administration. Hydrocortisone-loaded nanoparticles have potent effects on several tissues in rats