Functionalized hydroxyapatite scaffolds coated with sodium alginate and chitosan for controlled drug delivery

Due to its bioactivity, hydroxyapatite (HAp) is one of the most perspective materials for controlled drug delivery. Biodegradable polymers like chitosan and sodium alginate are used as coating materials for ceramic scaffolds. In this work the application of HAp/sodium alginate or chitosan composite materials which provide controlled lidocaine release is discussed. The polymers and lidocaine hydrochloride were incorporated in porous HAp scaffolds. Release of lidocaine hydrochloride was determined using high-performance liquid chromatography (HPLC). Depending on the polymer type used for coating, the crystal structure of the incorporated drug was determined. Drug/bioceramic scaffold/polymer interactions are discussed. The use of polymer coatings sustained lidocaine release from one day up to four days, compared with lidocaine impregnated but uncoated scaffolds.