3-Polythiophene Acetic Acid Nanosphere Anchored Few-Layer Graphene Nanocomposites for Label-Free Electrochemical Immunosensing of Liver Cancer Biomarker.

This study devised a label-free electrochemical immunosensor for the quantitative detection of alpha-fetoprotein (AFP). 3-Polythiophene acetic acid (3-PTAA) nanoparticles were anchored onto a few-layer graphene (FLG) nanosheet, and the resulting nanocomposite was utilized as the immunosensor platform. The AFP antibody (anti-AFP) was immobilized on 3-PTAA@FLG via a covalent interaction between the amine group of anti-AFP and the carboxylic group of 3-PTAA via ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) coupling. FLG is largely responsible for providing electrochemical signals, whereas 3-PTAA nanoparticles are well-known for their ability to be compatible with biological molecules in neutral aqueous solutions. Moreover, the carboxyl group present in 3-PTAA effectively binds anti-AFP through EDC/NHS conjugation. Owing to good dispersibility and higher surface area of 3-PTAA, it is very convenient for casting the polymer directly on the electrode substrate followed by immobilization of anti-AFP. Thus, it is feasible to regulate the activity of AFP proteins and control the spatial distribution of the immobilized anti-AFP proteins. The electrochemical sensing performance was assessed via cyclic voltammetry and electrochemical impedance spectroscopy. For an increase in the bioconjugate concentration, the results demonstrated a surge in charge-transfer resistance and a consequent decline in the current response. This approach effectively detected AFP at an extended dynamic range of 0.0001-250 ng/mL with a detection limit of 0.047 pg/mL. Furthermore, the sensing capacity of the immunosensor for AFP detection has been demonstrated to be steady in real human serum cultures. Our approach exhibits good electrochemical performance in terms of reproducibility, selectivity, and stability, which would surely impart budding applications in the clinical diagnosis of several other tumor markers.

Knowledge, attitude, and practice on digital eye strain during coronavirus disease-2019 lockdown: A comparative study.

BACKGROUND: Computer vision syndrome is a group of eye and vision-related problems that result from prolonged computer use. The worldwide pandemic of coronavirus disease-2019 (COVID-19) lockdown has led to an increase in the digital screen exposure as jobs as well as academic learning have majorly shifted online. This has caused an increase in digital eye strain (DES) globally. The aims and objectives of this study were to compare the knowledge, attitude, and practices among medical and nonmedical professionals with regard to DES in a background of COVID-19 lockdown. MATERIALS AND METHODS: A cross-sectional, observational, online questionnaire-based research survey analysis was conducted among medical professionals with age- and sex-matched nonmedical professionals. Responses were collected over a week and analyzed. The level of significance was set at a P < 0.05. Statistical Package for the Social Sciences software version 23.0 was used for the result analysis. RESULTS: Our study included 353 (50.4%) medical and 347 (49.6%) nonmedical personnel. It was noted that 266 (75.4%) of medical professionals and 268 (77.2%) of nonmedical professionals experienced eye problems after prolonged digital screen exposure. A significant proportion of respondents experienced an increase in symptoms following COVID-19 lockdown with 140 (52.6%) being medical professionals and 163 (60.8%) nonmedical professionals (P = 0.015). CONCLUSIONS: DES is a preventable lifestyle-associated disorder. Awareness among the masses can reduce the adverse effects. Proper lighting, adequate viewing distance, voluntary blinking, and using lubricating eye drops are a few ways to reduce the chances of DES. Further studies are needed to formulate standardized guidelines for the management of DES.