RESUMO
In recent years, several publications on microfluidic devices have focused on the process of electroporation, which results in the poration of the biological cell membrane. The devices involved are designed for cell analysis, transfection or pasteurization. The high electric field strengths needed are induced by placing the electrodes in close proximity or by creating a constriction between the electrodes, which focuses the electric field. Detection is usually achieved through fluorescent labeling or by measuring impedance. So far, most of these devices have only concerned themselves solely with the electroporation process, but integration with separation and detection processes is expected in the near future. In particular, single-cell content analysis is expected to add further value to the concept of the microfluidic chip. Furthermore, if advanced pulse schemes are employed, such microdevices can also enhance research into intracellular electroporation.
Assuntos
Células/metabolismo , Eletroporação/instrumentação , Eletroporação/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Animais , Eletrodos , Humanos , TransfecçãoRESUMO
Currently humic substances are removed from the raw water prior to chlorination by the conventional coagulation and filtration method using aluminium sulphate. Application of high-intensity (> 10 W/cm2) ultrasonic irradiation in conjunction with oxidative process using commercial oxidants H2O2 was investigated as an alternative. Sono-oxidation and sonodegradation of natural and synthetic humic substances have been followed over time by measuring total organic carbon (TOC) and absorbance by ultraviolet spectrometer (UV-VIS). It took approximately 60 min to reduce TOC by half and to have a complete degradation of humic acid.
Assuntos
Substâncias Húmicas/química , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Carbono/análise , Peróxido de Hidrogênio , Oxirredução , Espectrofotometria Ultravioleta , UltrassomRESUMO
Vegetative cells of Bacillus cereus were subjected to low doses of nisin (0.06 microg/ml) and mild pulsed-electric field treatment (16.7 kV/cm, 50 pulses each of 2-micros duration). Combining both treatments resulted in a reduction of 1.8 log units more than the sum of the reductions obtained with the single treatments, indicating synergy.
