Development and Upscaling of SiO2@TiO2 Core-Shell Nanoparticles for Methylene Blue Removal.

SiO2@TiO2 core-shell nanoparticles were successfully synthesized via a simple, reproducible, and low-cost method and tested for methylene blue adsorption and UV photodegradation, with a view to their application in wastewater treatment. The monodisperse SiO2 core was obtained by the classical Stöber method and then coated with a thin layer of TiO2, followed by calcination or hydrothermal treatments. The properties of SiO2@TiO2 core-shell NPs resulted from the synergy between the photocatalytic properties of TiO2 and the adsorptive properties of SiO2. The synthesized NPs were characterized using FT-IR spectroscopy, HR-TEM, FE-SEM, and EDS. Zeta potential, specific surface area, and porosity were also determined. The results show that the synthesized SiO2@TiO2 NPs that are hydrothermally treated have similar behaviors and properties regardless of the hydrothermal treatment type and synthesis scale and better performance compared to the SiO2@TiO2 calcined and TiO2 reference samples. The generation of reactive species was determined by EPR, and the photocatalytic activity was evaluated by the methylene blue (MB) removal in aqueous solution under UV light. Hydrothermally treated SiO2@TiO2 showed the highest adsorption capacity and photocatalytic removal of almost 100% of MB after 15 min in UV light, 55 and 89% higher compared to SiO2 and TiO2 reference samples, respectively, while the SiO2@TiO2 calcined sample showed 80%. It was also observed that the SiO2-containing samples showed a considerable adsorption capacity compared to the TiO2 reference sample, which improved the MB removal. These results demonstrate the efficient synergy effect between SiO2 and TiO2, which enhances both the adsorption and photocatalytic properties of the nanomaterial. A possible photocatalytic mechanism was also proposed. Also noteworthy is that the performance of the upscaled HT1 sample was similar to one of the lab-scale synthesized samples, demonstrating the potentiality of this synthesis methodology in producing candidate nanomaterials for the removal of contaminants from wastewater.

Proteins Derived from the Dairy Losses and By-Products as Raw Materials for Non-Food Applications.

The disposal of a high volume of waste-containing proteins is becoming increasingly challenging in a society that is aware of what is happening in the environment. The dairy industry generates several by-products that contain vast amounts of compounds, including proteins that are of industrial importance and for which new uses are being sought. This article provides a comprehensive review of the potential of the valorisation of proteins that can be recovered by chemical and/or physical processes from protein-containing milk by-products or milk surplus, particularly whey proteins or caseins. Whey proteins and casein characteristics, and applications in non-food industries, with special emphasis on the textile industry, packaging and biomedical, are reported in this review, in order to provide knowledge and raise awareness of the sustainability of these proteins to potentiate new opportunities in a circular economy context.

Clinical and Sociodemographic Aspects of Inflammatory Bowel Disease Patients.

BACKGROUND: In Brazil, there are few epidemiological studies available about the demographic and clinical aspects of inflammatory bowel disease (IBD). The aim of this study was to identify epidemiological and clinical characteristics of patients with IBD treated at the University Hospital (HU) of the Sergipe Federal University (UFS). METHODS: A cross-sectional descriptive study was conducted in HU/UFS from October 2011 to January 2014. The sample consisted of 87 patients with IBD, who registered in the coloproctology clinic. We applied a questionnaire with sociodemographic and clinical variables. RESULTS: Of the 87 patients, 40 (46%) had Crohn's disease (CD) and 47 (54%) had ulcerative colitis (UC). Women had a higher prevalence of IBD. Data obtained were significant (P < 0.05) in the variables: age, origin and level of education. CD patients were younger (< 25 years old), had higher prevalence of smoking habits and were associated with urban origin, conjunctivitis, palpable mass, appendectomy and intestinal complications. UC was more prevalent in older individuals (> 25 years old), with rural origin, bloody diarrhea and rectal bleeding. Location and initial behavior of CD were ileum-colic (L3), inflammatory behavior and penetrating form of the disease. There is higher prevalence of proctitis and mild and severe forms of the UC among women. Osteoarticular and systemic manifestations predominated in both diseases. CONCLUSIONS: IBD affected more women than men. The age, origin and level of education can interfere with early diagnosis. Demographic and clinical aspects were similar to the literature. Data differ in the time interval between the onset of symptoms and diagnosis, smoking habit, appendectomy and severity of UC for age and gender.