XYLAN-BASED MICROPARTICLES PRODUCED BY WATER-IN-WATER EMULSION AS A CARRIER FOR WATER-SOLUBLE LOW-MOLECULAR-WEIGHT DRUGS
xylan, water-in-water emulsion, drug encapsulation, calcium ions
The aim of the study was to produce xylan-based microparticles (XBM) containing 5-ASA using the water-in-water emulsification method, which avoids the use of organic solvents. The morphological analysis revealed spherical particles for all formulations within the size range of 4.77-10.7 µm. The entrapment of 5-ASA into XBM was below 4.0%. However, the addition of Ca2+ ions (XBM-Ca) increased the entrapment efficiency more than 10 folds. The characterization by ATR-IR did not reveal the presence of P=O bounds. On the other hand, the XBM-Ca had a sharp peak assigned to aromatic C-H bonds. The kinetic release profile of 5-ASA from XBM-Ca showed to be slow with 30% of the drug content released in 12 hours. The kinetic model that best fitted the data has a t-lag on it. Such drug retention time might indicate that the XBM-Ca can retain the drug until be exposed to xylanases. Thus, the XBM-Ca revealed themselves as potential candidates for colon-specific drug delivery systems