Coacervates based on citric pectin and polyethyleneimine

L. F. Balcewicz^a, I. C. Bellettini^b, I. C Riegel-Vidotti^a

^aDepartment of Chemistry, UFPR, Brazil

^bDepartment of Chemistry, UFSC, Brazil

(leticiafonseca@ufpr.br, www.gpmin.ufpr.br)

Complex coacervation is a process in which oppositely charged polyelectrolytes interact primarily through electrostatic attraction, leading to phase separation and the formation of a polymer-rich phase called coacervate. This phenomenon is used to create materials with tailored physicochemical properties for a wide range of applications¹. In this study, a detailed physicochemical investigation was conducted on the interaction between a natural polyanion, citrus pectin (PC), and a synthetic polycation, polyethyleneimine (PEI), driven by the unique properties of each. PC, a polysaccharide derived from citrus peels², contains carboxyl groups that can interact electrostatically with the amino groups of PEI, a polymer commonly used in gene therapy research³. By varying complexation conditions, it was observed that factors such as ionic strength and pH significantly influence the process. Salt concentration was found to impact the availability of charged groups on both polyelectrolytes, thereby affecting their ability to form electrostatic bonds. Complexes were characterized in terms of morphology, chemical structure via infrared spectroscopy, zeta potential, and yield. PEI:PC ratio up to 1:9 resulted in stable colloidal dispersions, with a surface charge of -9.8 mV and a hydrodynamic diameter of approximately 520 nm. The insights gained from this study on the PC-PEI pair provide valuable information for achieving desired material properties by understanding the mechanisms of coacervation.

Acknowledgements: CAPES/PROEX, CNPq.

References

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