The main objective of this study was to synthesize hydroxyapatite-ciprofloxacin composites using a chemical precipitation method and to evaluate the properties and in vitro release profile of the drug from the hydroxyapatite-ciprofloxacin composites. Composite characterization was achieved by FT-IR, XRD and DLS. Ciprofloxacin determination was accomplished by HPLC, resulting in good incorporation efficiency of the drug (18.13 %). The in vitro release study (Higuchi model C = K t1/2 and Ritger-Peppas model, C = K t0.6) showed a diffusion-controlled mechanism. The antibacterial activity showed that the bacterial growth inhibition zones were approximately equal for the synthesis composites and for the mechanical mixture on the Staphylococcus aureus germ. The use of hydroxyapatite, which is a biocompatible, bioactive and osteoconductive material, with ciprofloxacin, which has good antibacterial activity in this composite, makes it suitable for the development of bone grafts. Furthermore, the synthesis process allows a slow local release of the drug.

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A design of experiment (DoE) approach is presented for the optimization of Alendronate-hydroxyapatite nanoparticles� synthesis. The synthesis was performed using the chemical precipitation technique from calcium nitrate, diammonium hydrogen phosphate and alendronate. Synthesis temperature, reactant addition rate and ripening time were chosen as the most relevant experimental factors for our synthesis. Design of Experiments was used in order to measure these conclusive process parameters and their effect on controlling some final nanoparticles parameters, such us: alendronate incorporation efficiency (IncorporationEfficiency, %), hydroxyapatite crystallite size (Size_XRD, nm), hydroxyapatite particle size distribution (Size_DLS, �). Our study found that better HA-AL incorporation efficiency and small nonoparticles can be obtained using the following chemical process parameters: reaction temperature 30oC or smaller, ripening time 108h and addition rate 0.1mol/min. The analysis of more than one nanoparticles characteristics was possible using DoE software, MODDE 9.1. Thus, hydroxyapatite-alendronate incorporation efficiency should be expected to increase with decreasing temperature below 300C, increasing the maturate time at least 108h, at an addition rate of 0.1mol/min, in an N2 atmosphere. The same conditions will ensure nanoparticles small size that would be more desirable for the application of implants.

The objective of this study is to formulate and characterize ciprofloxacin-PLGA nanoparticles in laboratory. Ciprofloxacin-PLGA nanoparticles were obtained with Ciprofloxacin and PLGA as raw materials at the room temperature. The optimum set of process parameters were determined using Design of Experiments (DoE) with the factors: PLGA concentration, Ciprofloxacin concentration, Agitation Rate and the responses: Particles Size, Ciprofloxacin Encapsulation. The optimized formulation had 36.83% Ciprofloxacin Encapsulation and 87.58nm Particles Size in the conditions of 10% PLGA Concentration, 24.8 mg Ciprofloxacin Concentration and 1500 Rpm.

Implant infections are the result of bacterial adhesion to the implant surface and subsequent biofilm formation at the implant site. A sustained and high antibiotic concentration over minimal inhibitory concentration (MIC) of pathogenic bacteria at the implant site is expected to inhibit bacterial adhesion, colonization, and biofilm formation. In the present study we performed implants based on hydroxyapatite (HAp), HAp reinforced with titanium particles (HAp/Ti) and Hap/Ti with added calcium fructoborate (CaFb) by chemisorption deposition method (HAp/Ti/CaFb). The implants were immersed in ciprofloxacin (CP) solution for 24 hours, then was determined the release profile of antibiotic for 14 days and the antibacterial effect of the three types of composite. The period of antibiotic release may be considered as sufficient to support osteointegration under antibacterial protection.