Assessment of the effective parameters for the enhancement of light-harvesting power in the photoelectrochemical microbial fuel cell.

Photo-assisted microbial fuel cells (PMFCs) are novel bioelectrochemical systems that employ light to harvest bioelectricity and efficient contaminant reduction. In this study, the impact of different operational conditions on the electricity generation outputs in a photoelectrochemical double chamber configuration Microbial fuel cell using a highly useful photocathode are evaluated and their trends are compared with the photoreduction efficiency trends. As a photocathode, a binder-free photo electrode decorated with dispersed polyaniline nanofiber (PANI)-cadmium sulphide Quantum Dots (QDs) is prepared here to catalyse the chromium (VI) reduction reaction in a cathode chamber with an improvement in power generation performance. Bioelectricity generation is examined in various process conditions like photocathode materials, pH, initial concentration of catholyte, illumination intensity and time of illumination. Results show that, despite the harmful effect of the initial contaminant concentration on the reduction efficiency of the contaminant, this parameter exhibits a superior ability for improving the power generation efficiency in a Photo-MFC. Furthermore, the calculated power density under higher light irradiation intensity has experienced a significant increase, which is due to an increment in the number of photons produced and an increase in their chance of reaching the electrodes surface. On the other hand, additional results indicate that the power generation decreases with the rise of pH and has witnessed the same trend as the photoreduction efficiency.

Synthesis and modification of crystalline SBA-15 nanowhiskers as a pH-sensitive metronidazole nanocarrier system.

Clinical resistance to drugs and diminution in their side effects have become great issues for pharmacologists. In veterinary medicine, parasites like Trichomonas gallinae are of veterinary, hygienic and economic importance and can be treated by metronidazole. Unfortunately, scientific evidence has been reported about its resistance and serious side effects in trichomoniasis. In this research, it was attempted to introduce a new procedure to lower side effects of the drug molecules and also, enhance the treatment of disease. Whisker-formed SBA-15 nanoparticles were utilized for the first time in this issue. They had mesoporous structures which metronidazole molecules could be trapped in them. Additionally, these crystalline nanowhiskers were modified with tannic acid to make the release process better. The branches of tannic acid covered the opening of pores in crystalline SBA-15 nanowhiskers and restricted the drug from fast release. It caused a controlled metronidazole release in the smart drug delivery. These nanocarriers were completely tested by several experiments. Whisker-like SBA-15 nanocrystals had a mesopore volume of 0.5931 cm3/g, pore diameter of 6.06 nm and surface area of 491.38 m2/g. Based on TGA analysis, 10% of tannic acid was coated on the crystalline nanowhiskers during the modification. The metronidazole content and entrapment efficiency of final nanocarriers was 28.56% and 71.40%, respectively. The decomposition of tannic acid in lower pHs made whisker-like SBA-15@tannic acid nanocrystals be pH-responsive which can be used for other applications in the pharmacology. In-vitro study revealed that the minimal lethal concentration of nanocarriers was 0.5 mg/mL for 180 min.