Atmospheric-pressure plasma jets have been developed extensively for applications such as plasma medicine and plasma agriculture due to the generation of abundant reactive species being critical for manipulating reaction pathways in different fields. Therefore, it is essential to characterize the concentrations of reactive species introduced by plasma jets in the liquid phase for various applications. In this project, the concentrations of OH/NO2-/NO3- will be explored by using the microplate reader (spectrophotometer) under different operating conditions to reveal the correlations among reactive species generated in the liquid phase and the discharge parameters. Anyone interested in plasma technologies and characterization is welcome to join the project.