RESUMO
This study is about the use of ß-glycerophosphate (ßGP) to modulate the production of chitosan microparticles through a technology of jet break-up. ßGP has been described as capable of producing chitosan gels without additional complexing agents via a thermal transition (inverse gelation). A preliminary assessment on the effect of temperature on the viscosity and gelation of chitosan/ßGP precursors demonstrated that the crosslinking process was too slow to afford microparticle production via jet break-up. Instead, ßGP was used as a solubilizer to provide stable chitosan solution at neutral pH, which allowed the preparation of microparticles through polyelectrolyte complexation (with triphosphate) under physiological conditions, as opposed to the more conventional method of chitosan solubilisation in acids. Here, the key parameters of the microencapsulation process have been optimized, aiming to produce spherical particle of well-defined size and circularity, as well as toroidal microparticles, with a physico-chemical evaluation of the products.