You are presented with a paragraph from a COVID-19 literature. Classify the topics of this piece of text by choosing from the following categories:

- Epidemic Forecasting: The content relates to predictions about the spread of COVID-19.
- Treatment: The paragraph discusses therapeutic methods or medication for COVID-19.
- Prevention: The content covers measures to prevent the spread of COVID-19.
- Mechanism: The paragraph explains the biological mechanisms of the virus.
- Case Report: The content is a report of a COVID-19 case.
- Transmission: The paragraph discusses how COVID-19 is transmitted.
- Diagnosis: The content is about diagnosing COVID-19 in individuals.

Your classification should be provided as an element within a JSON array. The array should be formatted with topics enclosed in double quotes and separated by commas, following the JSON format, for example: ["Topic1", "Topic2", ...]. Include all applicable topics within the array. Your output should be a valid JSON array, and no additional text should be included in your response.

Article:

Exponential molecular amplification such as the polymerase chain reaction is a powerful tool that allows ultrasensitive biodetection. Here, we report a new exponential amplification strategy based on photoredox autocatalysis, where eosin Y, a photocatalyst, amplifies itself by activating a nonfluorescent eosin Y derivative (EYH(3-)) under green light. The deactivated photocatalyst is stable and rapidly activated under low-intensity light, making the eosin Y amplification suitable for resource-limited settings. Through steady-state kinetic studies and reaction modeling, we found that EYH(3-) is either oxidized to eosin Y via one-electron oxidation by triplet eosin Y and subsequent 1e(-)/H(+) transfer, or activated by singlet oxygen with the risk of degradation. By reducing the rate of the EYH(3-) degradation, we successfully improved EYH(3-)-to-eosin Y recovery, achieving efficient autocatalytic eosin Y amplification. Additionally, to demonstrate its flexibility in output signals, we coupled the eosin Y amplification with photoinduced chromogenic polymerization, enabling sensitive visual detection of analytes. Finally, we applied the exponential amplification methods in developing bioassays for detection of biomarkers including SARS-CoV-2 nucleocapsid protein, an antigen used in the diagnosis of COVID-19.
["Diagnosis"]