RESUMO Este trabalho teve como objetivo diminuir o tempo de formação de hidrogéis de fibroína utilizados na produção de scaffolds para aplicações na área médica e odontológica. Para a extração da fibroína foram utilizados os solventes: brometo de lítio e uma solução ternária (cloreto de cálcio + álcool etílico + água). Realizaram-se também modificações na membrana utilizada na diálise, de modo a diminuir o tempo para a formação de hidrogel e, consequentemente, obtenção dos scaffolds. A Tomografia por Transmissão de Raios-x confirmou a formação de scaffolds contendo 73,282% de porosidade total, sendo 73,272% de poros abertos interconectados, e densidade de conectividade entre os poros de 665,728 poros/mm3. A microscopia óptica mostrou que a estrutura dos scaffolds é constituída por fios com diâmetro de 24 µm. Por meio da espectroscopia infravermelho (FTIR) foi possível confirmar a presença das bandas de Amida I, II e III, caraterísticas da fibroína, ao final do processo de extração. A análise de DSC apresentou dois picos endotérmicos em 60 ºC e 297 ºC correspondentes à liberação de água e fusão da proteína, respectivamente. As modificações realizadas na membrana, proposta neste trabalho, diminuíram significativamente o tempo para a formação de hidrogel, precursor dos scaffolds, ocorrendo durante os três dias de diálise.

Energy dispersive X‐ray fluorescence (EDXRF) technique, as a qualitative and quantitative analysis, was used for inorganic chemical elements determination (K, S, Cl, Al, Si, Ca, Ti, Mn, Fe, Pb, Zn, Rb, and Bi) in eyeshadows for safe human use. International Nomenclature of Cosmetic Ingredients standardized nomenclature was used for labels investigation to obtain data on legal regularity. Data of 23 samples were clustered by similarity, measuring relative concentrations of detected chemical elements. Calculating the correlation among such values, a similarity matrix was used to generate a dendrogram. Pb was found in samples silver color S12E and copper color S22I above permissible limits (20 μg/g). Same composition was reported for the pink (S01A), black (S02A), and brown (S03A) samples, but the same chemical elements were not detected by EDXRF in them. The best correlation was found between samples S08D and S23 J (0.961). The least correlation was 0.0012 between S01A and S12E. The clustering analysis showed 7 groups of similar samples according to EDXRF data. Relations among 6 eyeshadows' colors and chemical compositions were discovered by using decision trees, where the most determinant elements were Mn, S, Cl, Ca, and Fe, in this order. Commercial regularization and International Nomenclature of Cosmetic Ingredients standardization of eyeshadows in Brazil are not fully complied by the manufacturers of the investigated brands.

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Silk produced by Bombyx-mori consists of two proteins sericin and fibroin. Silk Fibroin (SF) an attractive material for epithelial tissue regeneration. The aim of this study was to characterize membranes of PLDLAco-TMC:SF (2:1 w/w) once it could be used as a wound dressing to burn treatment and epithelial tissue regeneration. Membranes of Poly(L-co-D,L-lactic acid-co-TMC) with SF were prepared by casting method and it was analysed by: FTIR -there was no change in the PLDLA-co-TMC spectrum after SF has been added in polymers' solution, Swelling Test -the samples with SF had a different swelling behaviour of PLDLA-co-TMC. Membrane with SF showed swelling rate faster than PLDLA-co-TMC. Contact angle measurement -PLDLAco-TMC (1:1 w/w) showed a contact angle value higher than samples with SF. SEM -the addition of SF in PLDLA-co-TMC apparently leaves the polymer surface more roughened. Tensile test -there was a decrease in the Young's modulus and there was an increase in the elongation at break of PLDLA-co-TMC:SF membrane, DSC -SF did not change the glass temperature (Tg) of PLDLAco-TMC. The membrane of PLDLA-co-TMC:SF was characterized and it has potential to be used as a wound dressing to burn treatment and epithelial tissue regeneration.

Fibroin (FB) and bacterial nanocellulose (BC) are natural products, being used in biomedicine, electronics, food industries and other areas. Both show biocompatibility, able to be used for many different purposes. The blending of fibroin and bacterial nanocellulose was design to produce a biocompatible material to be applied with a medical device. For this reason, the objective of this work was to evaluate the structure properties of the blending of BC and FB. Thus, FB was extracted from Bombyx mori and BC was produced by fermentation process utilizing Gluconacetobacter xylinus. The membranes composed of BC-FB were produced by immersion contact for 24 hours, at 25°C, in 100rpm; without crosslinking agent. After the production the membrane samples were dried and characterized by Fourier transform infrared spectroscopy (FTIR spectroscopy), mechanical proprieties, swelling efficiency, scanning electron microscopy (SEM) and computerized microtomography (µCt). Results indicate that the hydrogen-bonded porous membranes obtained displayed anisiotropic, closed and interconnected porous morphology. The morphometric characteristics, which resemble a honeycomb and consist of a long structure with high connectivity and high total porosity, amplify the areas of BC-FB blend applications, with potential utilization with optoelectronic devices, in areas ranging from environmental to tissue engineering. Furthermore, the production by immersion contact will allow the upscale process and the development of green label material.