ABSTRACT
OBJECTIVE@#Late 2019 witnessed the outbreak and widespread transmission of coronavirus disease 2019 (COVID-19), a new, highly contagious disease caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Consequently, considerable attention has been paid to the development of new diagnostic tools for the early detection of SARS-CoV-2.@*METHODS@#In this study, a new poly-N-isopropylacrylamide microgel-based electrochemical sensor was explored to detect the SARS-CoV-2 spike protein (S protein) in human saliva. The microgel was composed of a copolymer of N-isopropylacrylamide and acrylic acid, and gold nanoparticles were encapsulated within the microgel through facile and economical fabrication. The electrochemical performance of the sensor was evaluated through differential pulse voltammetry.@*RESULTS@#Under optimal experimental conditions, the linear range of the sensor was 10 -13-10 -9 mg/mL, whereas the detection limit was 9.55 fg/mL. Furthermore, the S protein was instilled in artificial saliva as the infected human saliva model, and the sensing platform showed satisfactory detection capability.@*CONCLUSION@#The sensing platform exhibited excellent specificity and sensitivity in detecting spike protein, indicating its potential application for the time-saving and inexpensive detection of SARS-CoV-2.
Subject(s)
Humans , Microgels , Spike Glycoprotein, Coronavirus , COVID-19/diagnosis , Gold , Metal Nanoparticles , SARS-CoV-2ABSTRACT
Objective @#To investigate the combined effects of triclosan（TCS）and PCB153 on the activity of superoxide dismutase（SOD）and the concentration of malondialdehyde（MDA）in zebrafish liver.@*Methods @#Adult zebrafish were exposed to a series of concentrations of TCS,and the mortality in each group was observed and recorded during the acute toxicity test process. The concentrations in subsequent combined exposure experiments were arranged on the basis of the 96 h-LC50. The factorial design was used to determine the concentrations of combined exposure groups between TCS（0,0.125,0.5 μmol/L）and PCB153（0,0.05,0.2 μmol/L）. After 5,10 and 14 days of exposure,the zebrafish livers were dissected and frozen in each group. The potential interactions of these two compounds were analyzed according to the results of the SOD and MDA.@*Results @#The 96 h-LC50 of TCS exposed to adult zebrafish was 2.64 μmol/L（95%CI：2.37-2.89 μmol/L）. After 5 days of exposure,combined exposure to 0.5 μmol/L TCS+0.2 μmol/L PCB153 caused lower liver SOD activities than single exposure groups and the control group（P<0.05）. After 10 days of exposure,combined exposure to 0.125 μmol/L TCS+0.05 μmol/L PCB153,0.5 μmol/L TCS+0.05 μmol/L PCB153 caused lower liver SOD activities than single exposure groups and the control group（P<0.05）. After 14 days of exposure,combined exposure to 0.5 μmol/L TCS+0.05 μmol/L PCB153,0.5 μmol/L TCS+0.2 μmol/L PCB153 caused higher liver SOD activities than single exposure groups and the control group（P<0.05）. There was an interactive effect between TCS and PCB153 on the liver SOD activity in zebrafish（P<0.05）. There was no significant effect of MDA content in each group.@*Conclusion @#Combined exposure to TCS and PCB153 could enhance （inhibit first） the liver SOD activities in zebrafish,and the interaction was synergistic.