ZINC layered hydroxide salt intercalated with vitamin B3: novel slow-release food additive

Considering that many vitamins can be easily degraded, developing ways to avoid the degradation process and the availability of these vitamins is essential. Thus, this study aims to use layered zinc hydroxysalt (LHS) as a slow-release option that provides thermal stability for administering vitamins. Two compounds were synthesized, LHS/B3-1, which presented basal spacing of 9.63 Å, corresponding to a vitamin monolayer, and LHS/B3-2, which is a mixture of two phases, one with a basal distance of 9.92 Å and a secondary one with a basal distance of 15.43 Å, corresponding to a vitamin monolayer and bilayer, respectively. After intercalation, an increase of 175 °C in the thermal stability of vitamin B3 was observed, occasioned by the interaction with the layers of the matrix. Vitamin B3 was slowly released from LHS/B3-1 and LHS/B3-2, and 68.8% and 56.9% were released in 44 h, respectively. The release of the vitamin from LHS/B3-1 and LHS/B3-2 was divided into three stages. The results suggest that surface diffusion is initially involved in the release of B3 from intercalation products, where the anion dissociates from the surface of LHSs, followed by B3 release controlled by a diffusion process via intra-particle or surface diffusion.

Graphical Abstract