Desenvolvimento e Validação de Método para Separação de Isoflavonas em Extrato Seco de Soja

As isoflavonas são compostos fenólicos naturalmente encontrados em algumas plantas e são conhecidas como fitoestrogênios, compostos encontrados em alimentos derivados de plantas, primeiramente em produtos à base de soja. Neste trabalho foi desenvolvido um método de análise por Cromatografia Líquida de Alta Eficiência para separação e quantificação de isoflavonas presentes em extrato seco de soja. Para a validação do método, foram avaliados os parâmetros seletividade, precisão, exatidão, linearidade e faixa de trabalho, limite de detecção (LD), limite de quantificação (LQ), robustez e estabelecidos critérios de aceitabilidade para cada parâmetro. O método desenvolvido mostrou ser apropriado para determinação e quantificação de isoflavonas agliconas e glicosídicas presentes em extrato seco de soja

Volatile organic contaminants from plastic packaging: development and validation of analytical methods

Plastic packaging materials intended for use in food packaging is an area of great interest from the scientific and economic point of view due to the irreversible internationalization and globalization process of food products. Nevertheless, a debate related to food safety aspects has emerged within the scientific community. Therefore, the development of analytical methods that allow identifying and quantifying chemical substances of toxicological potential in the packaging is considered essential. This article focuses on the main analytical methods, including validation parameters, as well as extraction and quantification techniques for determination of volatile organic compounds from food packaging materials

Volatile organic contaminants from plastic packaging: development and validation of analytical methods

Plastic packaging materials intended for use in food packaging is an area of great interest from the scientific and economic point of view due to the irreversible internationalization and globalization process of food products. Nevertheless, a debate related to food safety aspects has emerged within the scientific community. Therefore, the development of analytical methods that allow identifying and quantifying chemical substances of toxicological potential in the packaging is considered essential. This article focuses on the main analytical methods, including validation parameters, as well as extraction and quantification techniques for determination of volatile organic compounds from food packaging materials3161522153

Volatile organic contaminants from plastic packaging: development and validation of analytical methods

Plastic packaging materials intended for use in food packaging is an area of great interest from the scientific and economic point of view due to the irreversible internationalization and globalization process of food products. Nevertheless, a debate related to food safety aspects has emerged within the scientific community. Therefore, the development of analytical methods that allow identifying and quantifying chemical substances of toxicological potential in the packaging is considered essential. This article focuses on the main analytical methods, including validation parameters, as well as extraction and quantification techniques for determination of volatile organic compounds from food packaging materials.3161522153

Methylparaben concentration in commercial Brazilian local anesthetics solutions

OBJECTIVE: To detect the presence and concentration of methylparaben in cartridges of commercial Brazilian local anesthetics. MATERIAL AND METHODS: Twelve commercial brands (4 in glass and 8 in plastic cartridges) of local anesthetic solutions for use in dentistry were purchased from the Brazilian market and analyzed. Different lots of the commercial brands were obtained in different Brazilian cities (Piracicaba, Campinas and São Paulo). Separation was performed using high performance liquid chromatography (HPLC) with UV-Vis detector. The mobile phase used was acetonitrile:water (75:25 - v/v), pH 4.5, adjusted with acetic acid at a flow rate of 1.0 ml.min-1. RESULTS: When detected in the solutions, the methylparaben concentration ranged from 0.01% (m/v) to 0.16% (m/v). One glass and all plastic cartridges presented methylparaben. CONCLUSION: 1. Methylparaben concentration varied among solutions from different manufacturers, and it was not indicated in the drug package inserts; 2. Since the presence of methylparaben in dental anesthetics is not regulated by the Brazilian National Health Surveillance Agency (ANVISA) and this substance could cause allergic reactions, it is important to alert dentists about its possible presence

Translocation of pesticides in coconut palm by endotherapy with the addition of different adjuvants

Commercial pesticides were selected, mixed and applied in coconut stems (Cocos nucifera Linn.) by endotherapy with various adjuvants. Tissue samples from the coconut stem were collected at different heights and days, and subjected to extraction and analysis by modified QuEChERS (“Quick, Easy, Cheap, Effective, Rugged and Safe") and UHPLC-MS/MS (ultra-high-performance liquid chromatography–tandem mass spectrometry). The translocations of 3-hydroxy-carbofuran, carbendazim, carbofuran, difenoconazole, imidacloprid, thiabendazole, thiamethoxam, thiophanate-methyl and spirodiclofen, using salts, citric acid and organosilicones as adjuvants, were evaluated and compared 2 and 30 days after the applications. The results showed that each pesticide had a different translocation profile, modified by the presence of the adjuvants. The most significant modifications were obtained using organosilicones, which enhanced the translocation process by 40% for most pesticides, followed by acidification (30%) and the addition of salts (22%).

Release of leachable products from resinous compounds in the saliva of children with anterior open bite treated with spur

To evaluate the release of bisphenol-A glycidyl methacrylate (BisGMA), triethylene glycol dimethacrylate (TEGDMA), bisphenol A (BPA), and phthalates of the composite resin used in the bonding of spurs applied in the treatment of children with anterior open bite and its effects on human keratinocytes. Methodology: Saliva samples of 22 children were collected before spur attachment (baseline) and 30 minutes (min) and 24 hours (h) after spur bonding. Analysis was performed using high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (HPLC–MS/MS) and gas chromatography coupled to mass spectrometry (GC–MS). Standardized resin increments were added to three different dilutions of the cell culture medium. Keratinocytes (HaCaT) were cultivated in the conditioned media and evaluated for cell viability (MTT) and cell scratch assay. Results: The levels of BisGMA (1.74±0.27 μg/mL), TEGDMA (2.29±0.36 μg/mL), and BPA (3.264±0.88 μg/L) in the saliva after 30 min, in comparison to baseline (0±0 μg/mL, 0±0 μg/mL, and 1.15±0.21 μg/L, respectively), presented higher numbers. After 24 h, the levels of the monomers were similar to the baseline. Phthalates showed no significant difference among groups. HaCat cells showed increased viability and reduced cell migration over time after exposure to methacrylate-based resin composites. Conclusion: Resin composites, used to attach spurs in children with anterior open bite during orthodontic treatment, release monomers after polymerization and can influence the behavior of human keratinocytes, even at very low concentrations. Orthodontists should be aware of the risks of the resinous compounds release and preventive procedures should be held to reduce patient exposure

Trends and perspective on future developments in liquid chromatography

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Sorção, imobilização e extração de polissiloxanos em silicas porosas para uso em cromatografia liquida de alta eficiencia

Orientadores : Carol Hollingworth Collins, Kenneth Elmer CollinsTese (doutorado) - Universidade Estadual de Campinas, Instituto de QuimicaDoutorad