The 4th Aquaphotomics International Conference was held on March 20-22, 2021 at Kobe University in Japan. More than 100 delegates from all over the world attended the conference, There are more than 20 representatives from China. Due to the epidemic, the conference was held conbining online with offline, the international representatives attended the meeting through online conference.

With the theme of “Exploring Water Molecular Systems in Nature”. There are 63 papers in the conference report, including 43 conference reports and 20 posters. The reports are divided into 13 conference units, the topic is the application of aquaphotomics (2 units), biological molecules hydration and a study of interfacial water (4 units), role of water in the life (2 units), basic research and new horizons (3 units), chemometrics (1 unit) and quantum brain dynamics (1 unit) ,respectively. The main content of this conference is the research and application of aquaphotomics and other related fields. The opening ceremony of the conference was presided over by Roumiana Tsenkova, who is the Professor at Kobe University in Japan. Federico Marini, associate professor at Sapienza University of Rome; Jelena Muncan, assistant professor at Kobe University in Japan; Xueguang Shao, professor in Nankai University; Masato Yusui, professor at Keio University School; Hengchang Zang, professor in Shandong University; Jean Michelle Roger, professor from National Research Institute for Agriculture, Food and Environment; Christian Huck, professor from the University in Innsbruck, Austria; Masato Takeuchi, associate Professor in Osaka Prefecture University, Japan; Christina Tonauer, Professor from University of Innsbruck, Austria, et al gave conference reports respectively.

Xihui Bian and Qian Liu of our research group attended the meeting and presented a poster titled “Spectrophotometric simultaneous determination of trace Cu2+ and Co2+ in aqueous solution by membrane preconcentration coupled with chemometrics”.