ABSTRACT
Hydrogen peroxide (H2O2) solution and its aerosols are common disinfectants, especially for urgent reuse of personal protective equipment during the COVID-19 pandemic. Highly sensitive and selective evaluation of the H2O2 concentration is key to customizing the sufficient disinfection process and avoiding disinfection overuse. Amperometric electrochemical detection is an effective means but poses challenges originated from the precarious state of H2O2. Here, an atomic Co-N-x-C site anchored neuronal-like carbon modified amperometric sensor (denoted as the CoSA-N/C@rGO sensor) is designed, which exhibits a broad detection range (from 250 nM to 50 mM), superior sensitivity (743.3 mu A mM(-1) cm(-2), the best among carbon-based amperometric sensors), strong selectivity (no response to interferents), powerful reliability (only 2.86% decay for one week) and fast response (just 5 s) for residual H2O2 detection. We validated the accuracy and practicability of the CoSA-N/C@rGO sensor in the actual H2O2 disinfection process of personal protective equipment. Further characterization verifies that the electrocatalytic activity and selective reduction of H2O2 is determined by the atomically dispersed Co-N-x-C sites and the high oxygen content of CoSA-N/C@rGO, where the response time and reliability of H2O2 detection is determined by the neuronal-like structure with high nitrogen content. Our findings pave the way for developing a sensor with superior sensitivity, selectivity and stability, rendering promising applications such as medical care and environmental treatment.
ABSTRACT
Background: To examine the outcomes heterogeneity of clinical trial protocols of coronavirus disease 2019 (COVID-19) to prioritize the establishment of a core outcome set. Methods: Databases of the International Committee of Medical Journal Editors - accepted clinical trial registry platforms were searched on February 14, 2020 and May 31, 2020. Randomized controlled trials and non-randomized controlled trials of COVID-19 were considered. Patient condition was classified as common, severe, or critical. Interventions included traditional Chinese medicine and Western medicine. We excluded trials that involved discharged patients, psychological intervention, and complications of COVID-19. The general information and outcomes, outcome measurement instruments, and measurement times were extracted. The results were analyzed by descriptive analysis. Results: In all, 19 registry platforms were searched. A total of 97 protocols were selected from among 160 protocols for the first search. For protocols of traditional Chinese medicine clinical trials, 76 outcomes from 16 outcome domains were reported, and almost half (34/76, 44.74%) of the outcomes were reported only once;the most frequently reported outcome was time taken for severe acute respiratory syndrome coronavirus 2 RNA to become negative. Twenty-seven (27/76, 35.53%) outcomes provided one or more outcome measurement instruments. Ten outcomes provided one or more measurement time frame. For protocols of Western medicine clinical trials, 126 outcomes from 17 outcome domains were reported;almost half (62/126, 49.21%) of the outcomes were reported only once;the most frequently reported outcome was proportion of patients with negative severe acute respiratory syndrome coronavirus 2. Twenty-seven outcomes provided one or more outcome measurement instruments. Forty (40/126, 31.75%) outcomes provided one or more measurement time frame. There were > 40 duplicated outcomes between the clinical trials protocols of traditional Chinese medicine and western medicine protocols. All of them were included in the Delphi survey when developing core outcome set for COVID-19. A total of 1,027 protocols were selected from 2,741 protocols for the second search. Forty-two new outcomes and 47 new outcome measurement instruments were reported. Conclusion: Outcome reporting in clinical trial protocols of COVID-19 is inconsistent. Thus, establishing a core outcome set is necessary for diagnosis and management.