Antimicrobiologic Property Hydrated Amorphous Calcium Phosphates Containing Silver

Abstract

The purpose of this study was to determine the microbiologic effect silver (Ag) when incorporated in amorphous calcium phosphate (ACP) prepared from solutions containing calcium, phosphate and pyrophosphate ions. The preparations were obtained from solutions with phosphate/pyrophosphate ratio, P/P2 = 7/3, and characterized as ACP using X-ray diffraction, infrared spectroscopy, nuclear magnetic resonance and differential thermal analysis. The microbes tested were cultures of E. Coli, St. aureus, Ps aerogunosa, C. diphteroides and C. albicans in media alone (control), with ACP without Ag and with ACP containing different Ag concentrations. Results demonstrated the following: (1) Ag in ACP inhibited the growth of microorganisms in all five cultures, with ACP containing 3-6% Ag giving the greatest antimicrobial effect; (2) sensitivity to the antimicrobial action of Ag differed among the bacteria.

Calcium Phosphate-Based Osteoinductive Materials

“…[61][62][63][64][65][66][67][68] CaPs are used as scaffolds in tissue engineering for bone or dentin regeneration [69][70][71][72][73] or delivery systems for drugs [73][74][75][76][77] or antibacterial agents. [78][79][80][81] CaPs are used in the form of injectable cements 17,[82][83][84] or as coatings on titanium and titanium alloy implants [85][86][87][88][89] to combine the bioactivity of the CaP and the strength of the metal. [87][88][89][90] CaP (HA, BCP) are used as abrasives (instead of alumina) to roughen metal implant surfaces.…”

Amorphous Calcium Orthophosphates: Nature, Chemistry and Biomedical Applications

“…In addition, other ionic substitutions are possible; however, such inorganic additives alter the ACP composition, which would enhance the negative effects in the biomedical application of ACP. Besides, with a few important exceptions, ion-substituted forms of ACP [34][35][36][37][38][39][40][41][42][43][44][45][46][47] are not discussed here.…”

“…As the majority of calcium orthophosphates are crystalline, this review is devoted to the detailed description of ACPs (emphasized by bold font in Table 1), which is of a great biomedical importance due to its chemical and structural similarities to the calcified tissues of mammals. Furthermore, with a few important exceptions, neither ion-substituted forms of ACP [34][35][36][37][38][39][40][41][42][43][44][45][46][47]347], nor ACP-containing biocomposites are considered and discussed. The readers interested in either these topics and/or other types of amorphous calcium phosphates (e.g., amorphous calcium polyphosphate [76][77][78][79][80] and amorphous calcium metaphosphate [81]) are referred to the original publications.…”

Antibacterial effect and cytotoxicity of Ag‐doped functionally graded hydroxyapatite coatings

“…The infection mechanism has been postulated as bacterial colonization on the prosthesis at the time of implantation by direct inoculation during manipulation of tissue and implantation or as a result of contaminated sterile implant 2. Recently, Ag/Ag + ,3–22 Cu 2+ /Zn 2+ ,18, 21 ampicillin,23 and doxycycline12 have been applied into HA‐coated implants to inhibit the adhesion and growth of bacteria. Among these antimicrobials, Ag/Ag + has broad inhibitory and bactericidal effects 7.…”

“…Although Ag is an antibacterial agent, it can be toxic to human cells if its concentration exceeds a threshold limit 8. Investigations have been conducted to study the threshold limit of Ag in HA, and various optimal concentrations of Ag in wt%,8, 9, 15 at. %,16 mol,17 and ppm18 in coatings have been reported.…”