Novel water-soluble polymers containing diosgenin moieties have been synthesized in order to study the proper conditions for the design of phytoactive formulations carrying brassinosteroid analogs. Samples are obtained by radical copolymerization between acrylamide (AM) and diosgenin monomaleate (DMM) at different initial feed compositions. The resulting copolymers present variable steroidal molar fractions ranging from 0.01 to 0.12, as calculated by means of 1H NMR spectroscopy. Mao–Huglin

more »

... od is employed for the estimation of monomer reactivity ratios, which renders 16.884 and 0.0024 for AM and DMM, respectively. Surface tension measurements evidence that copolymers with steroidal content below 0.1 exhibit aqueous stability with micelle formation. Controlled release of diosgenin moieties is achieved through alkaline hydrolysis of the monomaleate ester and followed by conductometry. The process displays second order kinetics with a suitable rate constant value for agricultural applications (0.061 L mol−1 s−1). The proposed formulation can also be extended for other applications of steroidal compounds.