Luana Roberta Michels

A surface modification of clozapine-loaded nanocapsules improves their efficacy: A study of formulation development and biological assessment.

This work aimed to develop nanocapsules (NC) coated with polysorbate 80 (P80), cationic chitosan (CS) or polyethylene glycol (PEG) using clozapine (CZP) as the drug model. The zeta potential, pH and encapsulation efficiency were directly affected by the CS coating. Using the bag dialysis method, the in vitro CZP release from CS-coated nanocapsules was similar to the PEG-coated at pH 7.4. Nanocapsules coated with PEG and CS exhibited an increased action duration compared to the P80-coated nanocapsules in pseudo-psychosis induced by d,l-amphetamine in rats. When comparing both groups, the group administered CS-coated nanocapsules showed better activity than the PEG-coated nanocapsules at 6, 10 and 12h after d,l-amphetamine administration. The pharmacokinetic assessment in rats demonstrated that the observed half-lives were free CZP<P80-coated<PEG-coated ̴ CS-coated nanocapsules. Both the P80- and PEG-coated nanocapsules showed a statistically significant increase in their volume of distribution compared to free CZP. On the other hand, the cationic nanocapsules showed a decrease in total clearance. Together, these results indicate that the PEG and CS coatings are a promising delivery system for CZP in the treatment of schizophrenia.

Quinine-Loaded Polymeric Nanoparticles: Validation of a simple HPLC-PDA Method to Determine Drug Entrapment and Evaluation of Its Photostability -

Article history: Received on: 01/11/2015 Revised on: 26/11/2015 Accepted on: 22/12/2015 Available online: 27/02/2016 Liquid chromatographic method was developed and validated for quantitative determination of quinine in polymeric nanoparticles. The method was performed using a Waters RP-18 column using a mobile phase consisting of acetonitrile:water:triethylamine (60:40:0.01 v/v/v, and pH aqueous phase adjusted to 3.0 with phosphoric acid). The flow rate was 1.0 mL min -1 and the detection was achieved with a UV-PDA set at 232 nm. The response was linear over a range of 12.0 to 24.0 μg.mL -1 (r = 0.9995). The relative standard deviation values for intra-day and inter-day precision studies were less than 2% and the accuracy was 98.8% to Nc1 and 97.3% to Nc2. The samples free of quinine and quinine-loaded polymeric nanoparticles were subjected to photodegradation conditions. A considerable reduction of degradation of quinine occurred in polymeric nanoparticles. Through these results, it was clear that the nanoencapsulation of quinine protects the drug from degradation by exposure to UV-A light. The analytical method was validated according to International Conference on Harmonization Guidelines and Center for Drug Evaluation and Research.

Educational Activities for Rural and Urban Students to Prevent Skin Cancer in Rio Grande do Sul, Brazil.

BACKGROUND Excessive exposure to the sun during childhood is strongly associated with the development of skin cancer in the future. The only way to prevent the development of skin cancer is to protect against ultraviolet radiation, which can be achieved through strategic awareness during childhood and adolescence. OBJECTIVE The aim of this work was to evaluate the impact of educational activities for rural and urban students to promote the use of sunscreens and prevent skin cancer. MATERIALS AND METHODS This study was carried out with students (9-12 years) of rural (n=70) and urban (n=70) schools in Rio Grande do Sul state, Brazil. The educational interventions were lectures and games. The impact of this strategy was evaluated through the application of a questionnaire before and after the interventions. RESULTS Before the intervention, it was found around 50% of rural and urban students were not aware of the damage caused by sun exposure, often exposing themselves to UV radiation without use sunscreen ( ~ 25 %) and at the most critical times of the day/year. After the lectures we observed an improvement in the behavior of the students with regard to sun exposure and knowledge about skin cancer. CONCLUSIONS The results of this study emphasize the importance of prevention strategies for skin cancer and promoting the use of sunscreens based educational strategies. The interventions were of great value in relation to disseminating knowledge on the subject.