Hidrogéis via base de Schiff a partir de ciclodextrina e polissacarídeos modificados: veículos para curcumina

Abstract

Curcumin (CUR) is a polyphenol with anti-inflammatory, antioxidant, and antimicrobial properties; however, its application is limited due to its low solubility and stability under physiological conditions. To overcome these limitations, CUR was initially encapsulated in 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), forming 1:1 inclusion complexes with a high complexation constant (4.65 × 10³ at 25 °C). The use of ultrasound for 10 min (HP-CD/Cur10) increased solubility (from 0.42 to 156 µg mL−1) and stability (half-life from 281 to 2139 min), while also providing antibacterial activity against S. aureus MRSA, greater bioaccessibility, and biocompatibility. In the second stage, HP-CD/Cur10 was incorporated into a hydrogel composed of succinylated chitosan and oxidized cashew gum (GEL-50B), resulting in the GEL-Cur4 formulation, which showed a high curcumin content (440 µg mL−1), mechanical and thermal stability, as well as injectability, self-healing, and adhesiveness. CUR release demonstrated pH responsiveness, increasing intestinal bioaccessibility from 0.20 to 13.5% and enhancing antibacterial activity against K. pneumoniae (85% vs. 59% in the control). In an in vivo wound model, GEL-Cur4 accelerated healing (71% vs. 41% in the control) and positively modulated markers of inflammation and oxidative stress. Therefore, the novel system developed represents a promising multifunctional matrix for wound healing and oral curcumin delivery.