Machine learning-assisted ammonium detection using zinc oxide/multi-walled carbon nanotube composite based impedance sensors.
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ABSTRACT:
SUBMITTER: Aliyana AK
PROVIDER: S-EPMC8692315 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:As the second wave of COVID-19 hits South Asia, an increasing deadly complication 'fungal infections (such as Mycosis, Candida and Aspergillus) outbreak' has been raised concern about the insufficient technologies and medicals for its diagnosis and therapy. Biosilica based nano-therapy can be used for therapeutic efficacy, yet their direct role as antibiotic agent with biocompatibility and stability remains unclear. Here, we report that a diatomaceous earth (DE) framework semiconductor composite conjugated DE and in-house synthesized zinc oxide (DE-ZnO), as an antibiotic agent for the enhancement of antibiotic efficacy and persistence. We found that the DE-ZnO composite had enhanced antibiotic activity against fungi (A. fumigatus) and Gram-negative bacteria (E. coli, S. enterica). The DE-ZnO composite provides enhancing large surface areas for enhancement of target pathogen binding affinity, as well as produces active ions including reactive oxygen species and metal ion for breaking the cellular network of fungi and Gram-negative bacteria. Additionally, the toxicity of DE-ZnO with 3 time less amount of dosage is 6 times lower than the commercial SiO2-ZnO. Finally, a synergistic effect of DE-ZnO and existing antifungal agents (Itraconazole and Amphotericin B) showed a better antifungal activity, which could be reduced the side effects due to the antifungal agents overdose, than a single antibiotic agent use. We envision that this DE-ZnO composite can be used to enhance antibiotic activity and its persistence, with less-toxicity, biocompatibility and high stability against fungi and Gram-negative bacteria which could be a valuable candidate in medical science and industrial engineering.
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Project description:Perovskite solar cells (PSCs) are regarded as the next-generation thin-film energy harvester, owing to their high performance. However, there is a lack of studies on their encapsulation technology, which is critical for resolving their shortcomings, such as their degradation by oxygen and moisture. It is determined that the moisture intrusion and the heat trapped within the encapsulating cover glass of PSCs influenced the operating stability of the devices. Therefore, we improved the moisture and oxygen barrier ability and heat releasing capability in the passivation of PSCs by adding multi-walled carbon nanotubes to the epoxy resin used for encapsulation. The 0.5 wt% of carbon nanotube-added resin-based encapsulated PSCs exhibited a more stable operation with a ca. 30% efficiency decrease compared to the ca. 63% decrease in the reference devices over one week under continuous operation. Specifically, the short-circuit current density and the fill factor, which are affected by moisture and oxygen-driven degradation, as well as the open-circuit voltage, which is affected by thermal damage, were higher for the multi-walled carbon nanotube-added encapsulated devices than the control devices, after the stability test.
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