Preparation and Characterization of Chitosan-Alginate Microspheres Loaded with Quercetin

Abstract

The aim of this paper was to formulate microspheres based on biodegradable polymers (chitosan and sodium alginate), using the complex coacervation technique. Subsequently, the prepared microspheres were loaded with quercetin (QUE), a pharmacological active ingredient insoluble in water and unstable to light, temperature and air. After preparation, the loaded microspheres underwent several studies for physical chemical characterization (performed by scanning electron microscopy—SEM, laser 3D scanning, and thermal analysis—TA). Furthermore, they were analyzed in order to obtain information regarding swelling index, drug entrapment, and in vitro release capacity. The obtained experimental data demonstrated 86.07% entrapment of QUE into the microspheres, in the case of the one with the highest Ch concentration. Additionally, it was proved that such systems allow the controlled release of the active drug over 24 h at the intestinal level. SEM micrographs proved that the prepared microspheres have a wrinkled surface, with compact structures and a large number of folds. On the basis of the TA analysis, it was concluded that the obtained microspheres were thermally stable, facilitating their usage at normal physiological temperatures as drug delivery systems.

pH Sensitive Quercetin Nanoparticles Ameliorate DSS‐Induced Colitis in Mice by Colon‐Specific Delivery

“…Thus pH-sensitive CDDS consisting of natural polysaccharides or their derivatives are receiving growing attention. [3,30] Chitosan is widely applied in gastrointestinal targeted drug delivery formulations, [10,31] suffers from obvious limitations in terms of its water solubility. [32] In the present study, we prepared quercetin nanoparticles made from higher water-soluble NSC with SA.…”

“…[9] Therefore, the use of polymers to develop nanoparticles to improve the bioavailability of oral quercetin has received extensive attention. [10] Traditional oral administration has limitations such as intragastric degradation and poor stability due to the high acidity of gastric juice, which affects the therapeutic effect of the drug. [11] Colon-specific drug delivery system (CDDS) refers to a drug delivery system that prevents premature release of the drug in the stomach after oral administration, but achieves release after entering the colon.…”

“…[ 9 ] Therefore, the use of polymers to develop nanoparticles to improve the bioavailability of oral quercetin has received extensive attention. [ 10 ]…”

Recent Reports on Polysaccharide-Based Materials for Drug Delivery

“…Among the composite systems studied, those based on chitosan and alginate are also of great importance. Literature data from the last few months indicate their numerous applications including e.g., mucus-penetrating nanoparticles with entrapped berberrine [ 172 ], ALG-coated chitosan nanoparticles for protein drugs’ [ 173 ] or tamoxifen citrate [ 174 ] protection, ALG/CS nanocarriers for co-delivery of doxycycline, florfenicol and silver nanoparticles [ 175 ], a nanoparticles-in-microparticles system for curcumin delivery [ 176 ], a physically and chemically crosslinked hydrogel composed of CS oligosaccharide and ALG for hydrophobic ketoprofen delivery [ 177 ] or CS/ALG microspheres loaded with quercetin [ 178 ]. On the other hand, Gierszewska et al [ 179 ] investigated pH-sensitive hydrogel membranes based on CS/ALG polyelectrolyte complex crosslinked by tripolyphosphate.…”

Sodium Alginate—Natural Microencapsulation Material of Polymeric Microparticles

“…The emergence of new processible, biocompatible, biodegradable and nontoxic biomaterials for the body in the field of medicine have made it possible to develop much more efficient and much more advantageous pharmaceutical systems than classical pharmaceutical forms. Thus, the category of new high-performance materials includes anionic natural polymers, such as sodium alginate, that are considered advantageous microencapsulation materials and which according to studies can influence the kinetics of the release of the drug from the matrix, according to their degradation in the body [ 10 , 11 ]. When developing particulated pharmaceutical forms, some of the main objectives of the formulation are to maintain the rate of release of the medicinal substance at an effective therapeutic level, with controlled speed and release time, and to protect the medicinal substances from gastrointestinal, enzymatic degradation, etc., and from the action of external factors [ 12 ].…”