New biomedical materials based on metal-doped fluorapatite

Abstract

In this paper, metal substitutions in the fluorapatite crystal matrix will be presented in order to obtain a new type of biomedical material. Fluorapatite has been intensively tested in recent decades as a building material for luminescent materials for many applications, from fluorescent lamps, through LEDs, to nanomaterials for high-tech biomedical applications. Fluorapatite has been shown to be non-toxic, extremely chemically stable and corrosion-resistant, as well as biocompatible, bioactive and osteoconductive. Also, fluorapatite proved to be a great host material for doping luminescent centers in the form of trivalent ions of rare earth and transition metals. Thanks to the position of the fluorine atom in the structure of the crystal lattice of fluorapatite, in the center of the Ca2 triangle (6h position) in the mirror planes at z = 1/4 and z = 3/4, this structure is extremely stable and stable. Also, the fluorine atom is responsible for the fact that fluorapatite, unlike hydroxyapatite, shows antibacterial properties. By touching different metals into this low phonon energy matrix, luminescent materials can be constructed that will emit light in the ultraviolet, visible or infrared region of the electromagnetic spectrum. If all these properties of fluorapatite are taken into account, their combination can lead to new materials for a wide range of biomedical applications.

U ovom radu biće prikazane supstitucije metala u kristalnom matriksu fluorapatita s ciljem dobijanja nove vrste biomedicinskih materijala. Fluorapatit se poslednjih decenija intenzivno ispituje kao materijal za izgradnju luminiscentnih materijala za široki spektar primena, od fluorescentnih lampi, preko LED dioda, do nanomaterijala za biomedicinske aplikacije visoke tehnologije. Fluorapatit se pokazao kao netoksičan, izuzetno hemijski stabilan i otporan na koroziju, a uz to i biokompatibilan, bioaktivan i osteokonduktivan. Takođe, fluorapatit se pokazao i kao sjajan materijal domaćin za dopiranje luminiscentnih centara u vidu trovalentnih jona retkih zemalja i prelaznih metala. Zahvaljujući položaju atoma fluora u strukturi kristalne rešetke fluprapatita, u centru Ca2 trougla (6h položaj) u ogledalskim ravnima na z = 1/4 i z = 3/4, ovakva struktura je izuzetno stabilna i postojana. Takođe, atom fluora je odgovoran što fluorapatit, za razliku od hidroksiapatita, pokazuje i antibakterijska svojstva. Dopiranjem različitih metala u ovu matricu niske fononske energije, mogu se konstruisati luminiscentni materijali koji će emitovati svetlost u ultravioletnoj, vidljivoj ili infracrvenoj oblasti elektromagnetnog spektra. Ako se uzmu u obzir sve ove osobine fluorapatita, njihovom kombinacijom mogu se dobiti novi materijali za široki spektar biomedicinskih primena.