Caracterização e estabilidade físico-química de sistemas poliméricos nanoparticulados para administração de fármacos

Polymeric nanoparticle systems such as nanocapsules and nanospheres present potential applications for the administration of therapeutic molecules. The physico-chemical characteristics of nanoparticle suspensions are important pre-requisites of the success of any dosage form development. The purpose of this review is to present the state of the art regarding the physico-chemical characterization of these drug carriers, in terms of the particle size distribution, the morphology, the polymer molecular weight, the surface charge, the drug content and the in vitro drug release profiles. Part of the review is devoted to the description of the techniques to improve the stability of colloidal systems.

Preparação e caracterização do complexo cobaloxima e sua utilização na construção de um eletrodo modificado: um experimento eletroquímico no curso de graduação

The present experiment describes the preparation, characterization of n-butyl(pyridil)cobaloxime complex and its electrochemical property. The infrared and uv-visible absorption spectra were used to characterize the complex obtained. The infrared spectrum of the compound showed characteristics bands that indicated the formation of the Co-C chemical bond formation. The electronic absorption spectrum in acetonitrile showed transition bands attributed to p-p*, metal-to-ligand charge transfer, d-d transitions and charge transfer Co-C. The electrochemical property was investigated by the pulse differential voltammetry technique. Two oxidation processes: Co(I)/Co(II) at -423 mV and Co(II)/Co(III) at 752 mV were observed.

Espectros eletrônicos de alguns complexos de geometria octaédrica de Ni2+: uma introdução prática à teoria do campo cristalino no curso de graduação

The experiment introduces the undergraduate students to the crystal field theory. The electronic spectra of the octahedral complexes of [Ni(L)n]2+ (L = H2O, dmso, NH3 and en) obtained in the experiment are used to calculate 10Dq and B parameters. The experiment shows how the parameters can be calculated and correlated with the nature of the ligands and the field intensities produced.

Gerenciamento dos resíduos da disciplina química inorgânica II do curso de química da Universidade Federal do Rio Grande do Sul

Beginning students in chemistry usually do not realize that wastes generated in their experimental classes constitute an environmental problem and that residues must be treated or disposed of in a suitable way. In this manuscript we describe the work that we have been doing in the inorganic chemistry course of the Federal University of Rio Grande do Sul with the objective of creating a critical consciousness in the students about the chemical wastes they generate. With this policy, students are required to take into account the nature of the residues they generate, how they can treat or segregate them, and how they can keep them in a suitable way for final destination, instead of simply throwing them away.

A criação do curso de engenharia química na escola nacional de química da universidade do Brasil

The goal of this work was to establish the origins of the chemical engineering course at the National School of Chemistry of the University of Brazil (at present, the School of Chemistry of the Federal University of Rio de Janeiro). There was a previous Industrial Chemistry course at the Higher School of Agriculture and Veterinary, established in 1920, following the French model. This course was the basis of the creation of the National School of Chemistry in 1933. During the 1940s, teachers and students claimed for a new course in true connection with the needs of the country and to reach full valorization of their job. The structure of the new Chemical Engineering course was approved in 1946 and the first class begun in 1952. This course was of great importance during the Brazilian industrial development during the 1950s and 1960s.

Tratamento estatístico dos parâmetros da qualidade das águas da bacia do alto curso do Rio das Velhas

Water quality was monitored at the upper course of the Rio das Velhas, a major tributary of the São Francisco basin located in the state of Minas Gerais, over an extension of 108 km from its source up to the limits with the Sabara district. Monitoring was done at 37 different sites over a period of 2 years (2003-2004) for 39 parameters. Multivariate statistical techniques were applied to interpret the large water-quality data set and to establish an optimal long-term monitoring network. Cluster analysis separated the sampling sites into groups of similarity, and also indicated the stations investigated for correlation and recommended to be removed from the monitoring network. Principal component analysis identified four components, which are responsible for the data structure explaining 80% of the total variance of the data. The principal parameters are characterized as due to mining activities and domestic sewage. Significant data reduction was achieved.

Perfil de leitores em um curso de licenciatura em química

The purpose of this study is to investigate the reading practice of undergraduate students of Chemistry, in a State University in Brazil. More specifically, we aim at showing students' habits and experiences concerning reading. Our research questions were: 1) What is the profile of readers in an undergraduate Chemistry course? 2) What can be perceived concerning students' reading experience? Results show that students' beliefs and practices are contradictory; although reading is considered by them as fundamental, they do not seem to have solid reading habits. This points to the necessity of rediscussing some aspects of Chemistry teacher formation.

Construindo o conhecimento através de projetos de trabalho: uma experiência no curso de química da universidade estadual de Santa Cruz

In this work, we describe a pedagogical experiment using work projects in chemistry undergraduate programs in general chemistry and inorganic chemistry courses making learning more dynamic and consolidating the link between students and the external community. We highlight as fundamental outcomes the improvement in the learning process and, above all, the active participation of the students in investigation and problem-solving activities.

A gestão de resíduos de laboratório na visão de alunos de um curso de graduação de quimica e áreas afins

This work presents the students´ profile before and after working in the course "Laboratory Chemical Waste Treatment" in the last ten years. The structure of the course is also described. Although students have shown an increasing previous experience on waste management, many fundamental aspects are missing, especially knowledge on the directives focusing environmental aspects. Visits to industrial plants are also essential to better understand the impact of wastes in environment. Most students nowadays consider waste management as an essential part of their professional formation. A good waste management program must consider several topics of extreme relevance.

Alameda Glette, 463, sede do Curso de Química da Universidade de São Paulo no período 1939-1965

As the foundation of the University of São Paulo completes 75 years, this article describes the history of a mansion at 463 Glette Boulevard, in São Paulo city, where several undergraduate courses of the University's Philosophy, Sciences and Letters Faculty operated until 1969. The first building of the school of Chemistry was erected there, 70 years ago. A brief retrospective of the Department of Chemistry at that place is given. The mansion was torn down by the middle of the 1970s, but it remained as a symbol of the school identity in the memory of all those who studied there.

O primeiro curso regular de química no Brasil

Chemistry gradually became a discipline in a number of institutions in Brazil after the arrival of the Portuguese court in 1808. The first of these was the Royal Military Academy in Rio de Janeiro, founded by the Prince Regent in 1810. Due to lack of local personnel for the post of Professor of Chemistry the British chemist Daniel Gardner was hired. He occupied that chair until his retirement in 1825. In this article we discuss the circumstances involving the creation of that chair, its occupant and the contents of his course.

Preparação e caracterização de suspensões coloidais de nanocarreadores lipídicos contendo resveratrol destinados à administração cutânea

Solid lipid nanoparticles (SLN), nanoemulsions (NE), and microemulsions (ME) were prepared by the hot solvent diffusion method, using tristearin or castor oil as oily phase, and soy lecithin and Solutol HS 15 as surfactants. Mean particle sizes ranged from 20 to 215 nm and negative zeta potentials were obtained for all nanocarriers. A HPLC method used to determine resveratrol was specific, linear, exact and precise. The entrapment efficiency was high for all formulations. However, resveratrol content was significantly varied among the lipid nanocarriers. Lipid nanocarrier containing hydrogels exhibiting pseudoplastic behavior were obtained after incorporation of hydroxyethylcellulose in the colloidal dispersions.

Concepções sobre currículo de formadores de professores: o curso de licenciatura em Química do Instituto de Química da Universidade Federal do Rio de Janeiro

In this paper, we discussed the conceptions of curriculum of teachers' trainers from de course of Chemistry from de Chemistry Institute and from the Education School of the Federal University of Rio de Janeiro. We understand that the curriculum results from a social construction, so, we intent to comprehend how happen the constitution of the course's curriculum, based on documents and interviews with the subjects of the research. The study showed that there were competitions for status, resources and territories between the Chemistry Institute and the Education School when the course was created, as well as there were internal competitions in the creation of the disciplines depending on the department of origin of the teachers.

Determinação da constante de dissociação (Ka) do captopril e da nimesulida: experimentos de química analítica para o curso de farmácia

This paper presents the determination of the dissociation constant (Ka) of captopril and nimesulide as contextualized experiments to teach chemical concepts to students of Pharmacy. Captopril is an antihypertensive drug, which presents high water-solubility and weak acid properties. The pKa of carboxylic acid group of captopril is 3.7. Nimesulide is a non-steroidal anti-inflammatory drug sparingly soluble in water. It is weakly acidic (pKa ≈ 6.5) because of its methanesulfonamide functional group. The pKa of captopril was determined by potentiometric titration with NaOH 2.0 x 10-2 moL L ¹. The pKa of nimesulide was determined by using spectrophotometry and photometric titration. The experimental values of pKa of both drugs are in very good agreement with those from literature

A propósito de cenários e atores: de que peça estamos falando? Uma luz diferente sobre o cenário da prática dos médicos em formação

O médico moderno precisa aguçar seus atributos humanos, adaptar-se a contextos variados e manter a educação permanente. A formação médica não costuma ocorrer no contexto da prática clínica real, mas no hospital, com ênfase na doença. As Diretrizes Curriculares Nacionais dos Cursos de Graduação em Medicina preconizam a articulação entre a universidade e o sistema de saúde e a habilitação à educação permanente. Logo, os cenários da prática devem ser os ambulatórios próprios dos serviços de saúde, com um aprendizado voltado para as necessidades de saúde da comunidade. Existe hoje um fortalecimento da Medicina Clínica Acadêmica, que combina cuidados de saúde com pesquisa, ensino e administração. O aluno deve assimilar a visão moderna da relação médico-paciente, respeitando as decisões compartilhadas, tarefa que exige trabalhar habilidades em comunicação. As instituições de ensino e de assistência à saúde são coadjuvantes neste processo, bem como os meios de comunicação. A inserção no cenário da prática médica tem que ser integrada a todas as disciplinas do curso, permeando o currículo e permitindo que o estudante volte sua atenção para as necessidades de saúde da comunidade. Estabelecer um currículo inovador exige que os educadores compreendam o esgotamento do modelo tradicional de ensino, fundamentado na doença e na transmissão de conhecimentos, que afasta o aluno da visão prática da Medicina. O enfoque pedagógico moderno enfatiza aspectos formativos. Seus principais domínios são: comportamento do paciente, atitude e papel do médico, interações médico-paciente e fatores socioculturais relativos aos cuidados com a saúde.