Breakthrough Discovery: Natural Zeolite Demonstrates Exceptional Antiviral Activity —Paving the Way for Low-Cost, Metal-Free Antiviral Materials

Graduate School of Engineering, The University of Tokyo

Nippon Paint Holdings Co., Ltd.

Key Points

• Through a systematic comparison of natural and synthetic zeolites, the research team led by Professors of Graduate School of Engineering, The University of Tokyo, and engineers of Nippon Paint Co., Ltd. discovered that natural mordenite-type zeolite (MOR) exhibits exceptionally high antiviral activity.
• The study identified the zeolite framework structure and surface acid strength as the key factors governing antiviral performance.
• The findings provide a foundation for developing low-cost, metal-free, environmentally friendly antiviral materials and establish new design guidelines based on zeolite surface acidity, with promising applications in public health and environmental protection.

Overview: Zeolite Framework Structure Plays a Critical Role in Antiviral Activity

Research Findings

A research team led by Professor Toru Wakihara of the Graduate School of Engineering, The University of Tokyo, in collaboration with Nippon Paint Co., Ltd., has demonstrated that the framework structure (topology) of proton-type zeolite (Note 1) is a key determinant of their antiviral performance.

To help prevent the spread of viral infectious diseases, there is an increasing need for solid materials that provide sustained antiviral activity over extended periods. Many existing zeolite-based antiviral materials rely on silver or copper ions; however, their practical application is limited by high cost, metal leaching, and discoloration.

In 2023, the research team became the first in the world to demonstrate that proton-type zeolites (H-type zeolites), which contain no metal ions, exhibit antiviral activity (see Related Press Release (1)). However, the specific zeolite framework structures responsible for high antiviral performance remained unknown.

In this study, the research team systematically compared multiple zeolite framework structures (Figure 1) and found that both natural mordenite (MOR-type) and its proton form (H-MOR) exhibit exceptionally high antiviral activity. Further structural characterization and surface acidity measurements revealed a strong correlation between antiviral performance and the acid strength of the zeolite’s external surface. These findings provide a foundation for the development of low-cost, environmentally friendly antiviral materials that do not rely on silver or other metals, while establishing new design guidelines for zeolite-based antiviral materials.

Figure 1: Antiviral Activity of Natural mordenite (MOR-Type) and Synthetic Faujasite (FAU-Type) Zeolites

〇Related Press Releases:

(1) Discovery of Novel Antiviral Activity of Proton-Form Zeolite―A Promising New Low-Cost, Discoloration-Resistant Antiviral Material with Broad Application Potential―(March 15, 2023)(Available only in Japanese)

https://www.t.u-tokyo.ac.jp/press/pr2023-03-15-002

(2) Joint Development of a High-Throughput Screening Platform for Novel Antiviral Materials (April 28, 2022) (Available only in Japanese)

https://www.t.u-tokyo.ac.jp/press/pr2022-04-28-002

(3) Joint Development of a Novel Antiviral Nanophotocatalyst That Inactivates SARS-CoV-2 and the Alpha Variant (July 15, 2021) (Available only in Japanese)

https://www.nipponpaint-holdings.com/news_release/2021071502/

(4) The University of Tokyo and Nippon Paint Holdings Establish Japan’s First Corporate-Sponsored Program Around the Concept of Paint and Coatings (November 24, 2020)

https://www.nipponpaint-holdings.com/en/news_release/2020112401/

Researchers and Affiliations

Graduate School of Engineering, The University of Tokyo

Toru Wakihara, Professor

Kohei Tsumoto, Professor

Makoto Nakakido, Lecturer

Masanori Takemoto, Assistant Professor

Yukie Okada (Master’s Program Student at the Time of the Research)

Nippon Paint Co., Ltd. Technology Division

Koichi Sato, Executive, Division Detector, Technology Division

Nobuhiro Miyamae, Group Manager, Protective Coatings Development

Yuki Egami, Architectural Coatings Department

Paper Information

Journal Name: ACS Nano

Title: Topology-Dependent Antiviral Activity of H‑Form Zeolites: Discovery of a Highly Active Natural Mordenite

Authors: Yukie Okada, Masanori Takemoto, Yuki Sada, Shoko Miyagi, Chokkalingam Anand, Makoto Nakakido, Noriko Nakamura, Seiichi Ohta, Naonobu Katada, Yutaka Yanaba, Nobuhiro Miyamae, Yuki Egami, Koichi Sato, Kenta Iyoki, Tatsuya Okubo, Kouhei Tsumoto, Toru Wakihara

DOI ：10.1021/acsnano.6c08119

URL：https://doi.org/10.1021/acsnano.6c08119

Research Funding

This research was supported by the Moonshot Research and Development Program of the New Energy and Industrial Technology Development Organization (NEDO); JSPS KAKENHI (Grants-in-Aid for Scientific Research), including Transformative Research Areas (A) (Grant Nos. JP20A206 and JP20H05880) and Scientific Research (S) (Grant No. JP23H05454); the Advanced Research Infrastructure for Materials (ARIM) program of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) (Grant No. JPMXP122324UT0343); and the Materials Processing Science Project "Materialize" (Grant No. JPMXP0219192801). These research findings were generated through a joint research project conducted under the Industry-Academia Co-creation Agreement, which was signed between the University of Tokyo and Nippon Paint Holdings Co., Ltd. on May 18, 2020.

Glossary

(Note 1) Proton-type Zeolite: A zeolite in which hydrogen ions (protons) are incorporated into the crystal structure.