RESUMO
Current efforts in stomach-related drug design focus on improving drug bioavailability within the gastric region. Bacterial nanocellulose (BNC) has been established as a suitable material for drug delivery systems; however, it lacks adhesion to the gastric environment. This limitation can be addressed by leveraging the mucoadhesive properties of low molecular weight chitosan (LMWC). Therefore, we aimed to develop mucoadhesive capsules constructed from BNC coated with crosslinked LMWC, intended for targeted drug delivery in the gastric region. The capsules were characterized using scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and mucoadhesion assessments. Under acidic conditions, crosslinked chitosan exhibited enhanced swelling relative to neutral conditions. The coating of chitosan onto the BNC fibrillar network of the capsules resulted in the superimposition of vibration bands and enhanced thermal stability. Furthermore, the capsules exhibited significant mucoadhesive properties in the gastric environment, with an attachment force measuring 89.151 ± 6.226 mN. To validate the efficacy of the system, we utilized antioxidant turmeric extract (TE) as a bioactive compound with chemopreventive potential against stomach cancer. TE was adsorbed onto BNC in a reversible multilayer system, enabling controlled adsorption and desorption. These findings highlight the significance of developing mucoadhesive capsules as a tailored drug delivery system for gastric conditions, particularly in the context of treating stomach diseases as cancer.
RESUMO
This paper presents the results obtained from the chemical activation of bacterial nanocellulose (BCN) using fique juice as a culture medium. BNC activation (BNCA) was carried out with H3PO4 and KOH at activation temperatures between 500 °C to 800 °C. The materials obtained were characterized morphologically, physicochemically, superficially, and electrochemically, using scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), the physisorption of gases N2 and CO2 at 77 K and 273 K, respectively, cyclic voltammetry, chronopotentiometry, and electrochemical impedance spectroscopy (EIS). The samples activated with H3PO4 presented specific surface areas (SBET) around 780 m2 g-1, while those activated with KOH values presented specific surface areas between 680 and 893 m2 g-1. The XPS analysis showed that the PXPS percentage on the surface after H3PO4 activation was 11 wt%. The energy storage capacitance values ranged between 97.5 F g-1 and 220 F g-1 by EIS in 1 M H2SO4. The samples with the best electrochemical performance were activated with KOH at 700 °C and 800 °C, mainly due to the high SBET available and the accessibility of the microporosity. The capacitance of BNCAs was mainly improved by electrostatic effects due to the SBET rather than that of pseudocapacitive ones due to the presence of phosphorus heteroatoms.