Release of amoxicillin from polyionic complexes of chitosan and poly(acrylic acid). study of polymer/polymer and polymer/drug interactions within the network structure

Films based on chitosan polyelectrolyte complexes for skin drug delivery: Development and characterization

“…If there is a high degree of swelling, the complex can be dissolved. If we are maximizing the grade of network complexation through the maximization of the number of the electrostatic interactions between the two oppositely charged polymers, we are increasing the stability of the network, that will lead to a reduction of the swelling/eroding behaviour of the PEC and, as a consequence, the tighter network will exhibit properties that allow the controlled release of drugs without the need of crosslinkers [9,24].…”

“…In this work, PEC are based on chitosan and crosslinked poly(acrylic acid) (PAA) polymers. Hydrogels prepared with a wide range of ratios between chitosan and crosslinked PAA have been successfully prepared for different applications such as the amoxicillin site-specific delivery in stomach [9,14] or the buccal delivery of acyclovir [8] and provided a suitable drug controlled release profile. Crosslinked PAA polymers are water insoluble, have the ability to swell in water and its low glass transition temperature reflects a non-rigid structure [15].…”

“…Crosslinked PAA polymers are water insoluble, have the ability to swell in water and its low glass transition temperature reflects a non-rigid structure [15]. Chitosan, in combination with other polymers and molecules, has been used in several studies of PEC for the controlled delivery of drugs through different routes of administration, e.g., oral [9,16], buccal [8], subcutaneous [17], colonic [18,19], transmucosal [20] and ophthalmic [21].…”

“…The pH and the amount of each polymer was chosen so as to obtain a ratio of one between the positively charged groups of chitosan and the negatively charged groups of the PAA and thus maximize the number of potential sites for electrostatic interaction. This pH value was used to prepare all PEC films, based on the assumption that hydrogels with a maximum number of electrostatic interactions would give a tighter structure, improving the stability of the network which would be reflected in a decreased swelling and drug release [9]. Increased crosslinking density and lower degree of swelling also tend to decrease the degree of burst release, minimizing the risk of dose dumping that can be potentially harmful to patients [22,23].…”

Chitosan/Polyethylene Glycol Beads Crosslinked with Tripolyphosphate and Glutaraldehyde for Gastrointestinal Drug Delivery

“…Examples of PECs for controlling drug release include alginate/CS (3,4), CS/carrageenan (5), CS-cellulose multicore microparticles (6), CS-coated pectin (7), CS/poly(acrylic acid) complexes (8), poly(vinyl alcohol)/sodium alginate blend beads (9), and poly(methacrylic acid-g-ethylene glycol) particles (10).…”