The Controller of Patents, Patent Office, Government of India, has awarded the patent
entitled “A Water-in-Water Pickering Emulsion Based Nano Complex Foliar Fertilizer and
Preparation Method Thereof” to TNAU for developing a liquid fertilizer suitable for drone
spraying. This patented technology is the result of research conducted at the Centre for
Agricultural Nanotechnology by Ph.D. scholar Dr. D. Pradeep, under the guidance of
Dr. K. S. Subramanian and Dr. S. Marimuthu.
Due to labour shortages, many farmers have shifted to using liquid nitrogen fertilizers
with drones, which has often led to spray drift, poor efficiency, and low nitrogen levels in
crops. To address these challenges, the researchers adopted the Pickering emulsion technique
to increase the nitrogen content of the liquid fertilizer. In this technique, the nutrient is
encapsulated with silica nanoparticles cross-linked using polyethylene glycol, increasing the
nitrogen content to around 32–36%. This new nano fertilizer has higher density and improved
stability, enabling more accurate nutrient delivery and minimizing drift during application.
The Patent Cell of the School of Postgraduate Studies supported the entire patent process,
including drafting, filing, and coordination with the patent attorney.

Tamil Nadu Agricultural University
Coimbatore is all Set to Announce the International Conference on “Emerging Post Harvest Technologies for Shelf Life Enhancement and Valorization of Horticultural Crops”
Overview Horticultural College and Research Institute, Coimbatore of Tamil Nadu Agricultural University, (TNAU) in association

