info:eu-repo/semantics/conferenceProceedings All rights reserved In this work, a new formulation that gradually released encapsulated Thuja plicata essential oil (TPEO) as an active component from a biopolymer matrix within a given period was obtained. Firstly, biopolymer matrix consisting of a chitosan-gelatin mixture was prepared. Afterwards, TPEO essential oil was encapsulated into the biopolymer matrix and an oil-in-water emulsion was formed. The main goal of this work was to obtain stable formulation by optimizing synthesis parameters (biopolymers ratio, amount of Tween 80 and homogenization time). FTIR spectra analysis confirmed that the addition of gelatine to the chitosan solution contributed to the forming of strong electrostatic interaction between these polymers, and also revealed hydrogen interactions between active components of TPEO (methyl thujate) and polymer chains. By optimizing biopolymers ratio and amount of Tween 80, nanoemulsion with average droplet size around 150 nm was obtained. The stability of the emulsions was confirmed by zeta potential measurements, with the value of about 30 mV, even after 14 days of ageing at room temperature. Ćirković, Jovana Radojković, Aleksandar Jovanović, Jelena Perać, Sanja Branković, Zorica Milenković, Ivan Milanović, Slobodan Dobrosavljević, Jovan Tadić, Vanja Žugić, Ana Branković, Goran https://unilib.phaidrabg.rs/o:7922 cobiss:170258441 ISBN: 978-86-80109-27-5 application/pdf 793162 bytes 2025 BOOK OF ABSTRACTS startpage: 56 endpage: 56 eng PREPARATION OF BIOPOLYMER BASED PESTICIDE AGAINST PHYTOPHTORA PATHOGENS