Development of new formulations for soil pest control

Abstract: In formulation science, there are few systematic investigations on encapsulation ofagro-biologicals with regard to materials, methods and technology for mass production. The aimof this work was to develop novel mechanically stable capsule systems with increased persistencein soil. To this end, we tested different methods with several biopolymers, combinations ofbiopolymers and lignin as capsule additive. Capsule systems were prepared by ionic gelation,thermal gelation, complex coacervation and additional bead coating. In selected capsules, ligninwas incorporated. Capsules based on single biopolymers were able to form stable sphericalcapsules, e.g. alginate, pectin derivates and gelatin. Capsules based on combinations of polymersalso showed stable capsule formation, e.g. alginate/gelatin, alginate/lignin and SEC/PDADMAC.Additionally, lignin was used successfully as additive in SEC hollow beads. First experimentsindicate significant differences in biological degradability and thus persistence in soil withdifferent capsule systems. These novel capsule systems with increased persistence are suitable fordelivery of BCAs into the soil.