Gastro‐resistant controlled release of OTC encapsulated in alginate/chitosan matrix coated with acryl‐EZE® MP in fluidized bed

Abstract

A gastro‐resistant system of acryl‐EZE® MP coated alginate/chitosan microparticles was developed to improve the controlled release of oxytetracycline (OTC). Microparticles were obtained by complex coacervation and, thereafter, were coated using fluidized polymer dispersion with acryl‐EZE® MP solution. OTC distribution inside the microparticles was determined by multiphoton confocal microscopy, demonstrating the efficiency of encapsulation process. In vitro OTC release kinetic was performed in order to obtain the release profile in gastric and intestinal simulated fluids. A fast initial release, or burst effect, was observed with uncoated microparticles loaded with OTC in gastric conditions. When a 50% mass increase in acryl‐EZE® MP coating was achieved, OTC release in acidic medium was greatly reduced, resulting in the expected gastro‐resistant effect. Different mathematical models were applied to describe the drug diffusion across the polymer matrix. The Logistic model was the best tool to interpret the experimental data in most of the systems studied. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40444.

Alginate Particles for Encapsulation of Phenolic Extract from Spirulina sp. LEB-18: Physicochemical Characterization and Assessment of In Vitro Gastrointestinal Behavior

“…The release profile of the PC was determined according to the procedure described by Barbizan [ 42 ]; Kleinubing [ 43 ], with some modifications. The release of PC of microalgae was evaluated by immersing the alginate particles in HCl at pH 1.5, and in PBS at pH 7.2, to simulate the pH of gastric and intestinal environments, respectively.…”

Silver nanoparticles incorporated into nanostructured biopolymer membranes produced by electrospinning: a study of antimicrobial activity

“…In recent years, our research group has been dedicated to the study of nanostructured biopolymer Silver nanoparticles incorporated into nanostructured biopolymer membranes produced by electrospinning 913 membranes for application in the medical and dental fields (Nista et al, 2012;Nista et al, 2013;Nista, Bettini, Mei, 2015;Bizarria, Davila, Mei, 2014;Kleinubing et al, 2014).…”

“…Recent studies have shown that an especially lucrative opportunity lies in applying these polymeric nanostructures in the medical field (Abdelgawada, Hudsona, Rojas, 2014;Chaloupka, Malam, Seifalian, 2010;Dallas, Sharma, Zboril, 2011). The literature contains a great deal of studies demonstrating the successful application of these nanostructures in the healthcare, pharmaceutical and cosmetic industries for repairing and regenerating the skin and organs; as drug delivery vectors and therapies; biocompatible and biodegradable implants; in medical diagnosis and instrumentation; as tissue protective agents that guard against infection; and in cosmetics, molecular medicines, supplements and body care applications in the field of dentistry (Nista, Bettini;Mei, 2015;Bizarria, Davila, Mei, 2014;Kleinubing et al, 2014).The AgNPs possess superior antimicrobial properties compared to other salts, due to their extremely large surface area, which provides better contact with microorganisms (Rai, Yadav, Gade 2009). Although the mechanism of action of silver nanoparticles on microorganisms is not fully understood, there are hypotheses that these nanoparticles can cause cell lysis or inhibit cell transduction (Prabhu, Poulose, 2012).…”

“…The authors showed that the polymeric solution (PVA/GK/Ag) and the final AgNP-containing membrane (Ag-MEM) exhibited clear antibacterial activity toward Gram-negative E. coli and P. aeruginosa and Gram-positive S. aureus. These newly synthesized nanomaterials show great potential for the development of environmentally friendly antibacterial devices for medical, food packaging, and water purification purposes (Padil et al, 2015).In recent years, our research group has been dedicated to the study of nanostructured biopolymer Silver nanoparticles incorporated into nanostructured biopolymer membranes produced by electrospinning 913 membranes for application in the medical and dental fields (Nista et al, 2012;Nista et al, 2013;Nista, Bettini, Mei, 2015;Bizarria, Davila, Mei, 2014;Kleinubing et al, 2014).This work focuses on the synthesis, characterization, and comparative antimicrobial activities of AgNPs incorporated into nanostructured biopolymer membranes made from either a blend of CTS/PEO or CA when tested against both Gram-positive and Gram-negative bacteria. …”