Highly-sensitive and rapid detection of COVID-19 in wastewater: a comprehensive review based on graphene field effect transistor biosensor

The novel Corona Virus Disease 2019 (COVID-19) has been spread from the Wuhan city of China has now affected many countries;it is still circulating worldwide. Consecutive studies of finding the RNA of this virus in sewage systems increase renewed interest about COVID-19 faucal transmission and its pathogenic issue on sanitation and wastewater systems. Municipal wastewater is typically remarked as one of the major end routes of different types of emerging contaminants such as pharmaceuticals, endocrine disruptors, antibiotics, micro plastics, pesticide and heavy metal residues associated with antimicrobial resistance. Currently all available, antibodies based and molecular base testing have some limitations for this purpose: whole coronavirus particles instead of pure antigen proteins need to be tested in a short time and take control of the pandemic of COVID-19. The current study helped in understanding, concept and demonstrated the potential of graphene Field Effect Transistor (FET) technology for sensitive and rapid detection of corona viruses. Therefore, extra trustworthy, quick response, economical and broadly accessible analytical devices or diagnostic approaches are crucially required. We have critically reviewed and argued the biomarkers and indicators used for COVID-19 diagnostics or SARS-CoV-2 detection. In this regard, ultrasensitive graphene FET biosensors are powerful tools in early diagnosis of COVID-19 infection via targeting virus S1 protein to assess the clinical progress and offer awareness on severity and critical trends of infection.

Contextual teaching learning during covid-19 pandemic with electronic student worksheet design

The Covid-19 pandemic has an impact on the learning in schools. The ability to think critically can be taught to students through teaching materials that are appropriate to students' needs. This study aims to analyze and design electronic student worksheets based on Contextual Teaching Learning (CTL) learning models to stimulate students' critical thinking skills, during the Covid-19 pandemic. This study uses an R&D research and development approach to produce student worksheet designs. The subjects of this study were teachers and grade X students, Muhammadiyah 1 Yogyakarta Vocational High School. This research is a qualitative descriptive study. The research data were collected using research instruments in the form of interview guidelines, questions, and observation guidelines. The research data were analyzed by using the model of Miles and Huberman. The results showed that competency standards, core competencies, basic competencies, and indicators of competency achievement in accordance with the 2013 curriculum. Students' critical thinking skills still need to be improved. CTL is one of the learning models that can be applied to improve critical thinking skills. The teacher requires an electronic student worksheet that is appropriate to the CTL model. In addition, this study produced an Electronic Student Worksheet design that was appropriate to the needs analysis. The electronic student worksheet was designed according to the CTL model and for critical thinking skills. This research could be developed at the development, implementation, and evaluation stages.