Journal of Alloys and Compounds 536S (2012) S432–S436 Contents lists available at SciVerse ScienceDirect Journal of Alloys and Compounds j our na l ho me p ag e: www.elsevier.com/locate/jallcom Preparation of hydroxyapatite nanoparticles facilitated by the presence of -cyclodextrin Carlos A. Martínez-Pérez a,* , Jorge García-Montelongo a , Perla E. Garcia Casillas a , José R. Farias-Mancilla a , Humberto Monreal Romero b a Institute of Engineering and Technology, Autonomous University of Juarez, UACJ, Ave. del Charro #610 norte, C.P. 32320, Cd. Juárez, Chihuahua, Mexico b School of Odontology, Autonomous University of Chihuahua, UACH, Ave. Universidad s/n Campus Universitario I, C.P. 31170, Chihuahua, Mexico a r t i c l e i n f o Article history: Received 27 June 2011 Received in revised form 23 December 2011 Accepted 26 December 2011 Available online 31 December 2011 Keywords: Nanoparticles Hydroxyapatite Biomaterials a b s t r a c t Hydroxyapatite nanoparticles with uniform morphology have been successfully synthesized by a chemi- cal coprecipitation method and facilitated by the presence of the -cyclodextrin. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM); and Fourier Transformed Infrared Spectroscopy (FT-IR) were used in order to characterize the hydroxyap- atite samples. The experimental results indicate that the obtained HA is in the range of 20–50 nm. Also it was found that the content of -CD has an impact on the purity of the HA as well in the particle size of the hydroxyapatite nanoparticles. © 2012 Elsevier B.V. All rights reserved. 1. Introduction It is well known that hydroxyapatite (HA) is the principal inor- ganic constituent of bones and teeth. The importance of HA has led to extensive research in numerous areas ranging from the physic- ochemical mechanisms of the formation to its applicability as a biomedical or industrial material [1]. In particular, the biocom- patibility and osteoconductive properties have made HA a useful materials for implants [2]. HA have been used as filler for bone defect [3]; as coating on different materials as hip prosthesis [4]; or as composite [5]. The importance of HA have led to develop differ- ent methods of production that have been produced HA particles of different shapes as needles, spherical nanoparticles, rods, etc. [6–10]. The research on HA has led to new and interesting applica- tions like its use in the form of nanoparticles to treat cancer cells [11–14]. On the other hand, cyclodextrin (CD) is water-soluble oligosac- charides composed of at least six (1–4) linked -d-glucosyl residues which have the shape of a hollow, truncated cone, capable of forming inclusion complexes with a variety of guest molecules in the solid state, as well as in solution, with sizes compatible with the dimensions of the cavity [15]. Despite there * Corresponding author. Tel.: +52 656 688 4887. E-mail address: camartin@uacj.mx (C.A. Martínez-Pérez). are several reports that use hydroxyapatite or calcium phosphate with -CD to form a composites or inclusion complex, there a few publications that use the CD in order to control particle size and morphology; only a report that use the -CD for the preparation of HA particles was found but it was reported the production of particles with micrometer size with its methodology [16], In this context, this work report the influence of the CD in the production of hydroxyapatite nanoparticles by the chemical co-precipitation method. 2. Materials and methods -Cyclodextrin (99.9%) was purchased from ACROS ORGANICS Co., phosphoric acid 85% (H3PO4) and calcium chloride (CaCl2) were obtained from J.T. Baker, sodium hydroxide (NaOH) from Fisher Scientific; all chemical were of analytical degree and used as were received without further purification. A calcium chloride solution was prepared by dissolving 2.775 g of CaCl2 in 30 ml of distilled water. Solutions of H3PO4 were prepared by the addition of 1.729 g of phosphoric acid in 50 ml of distilled water and the pH was adjusted to 13, with a 1 M NaOH solution. To the phosphoric acid solution, -CD was added at concentration ranging from 0 to 5 wt.% measured with respect to the calcium chloride. CaCl2 solution was added dropwise into the phosphate/CD solution under vigorously stirring. The solution was dried at 90 ◦ C for 24 h. The obtained HA powder was washed with distilled water and again dried at 100 ◦ C for another 24 h. Finally, the samples were annealing at 550 ◦ C for 6 h. Powder X-ray diffraction patterns were recorded on a X’Pert Pro PANalytical diffractometer using radiation Cu K at 30 kV and 20 mA and the determi- nation of phases and analysis of XRD patterns was made with the software X’Pert High Plus. The morphology of the samples was performed on a Field Emission Scanning Electron Microscopy JEOL JSM7000F and Field Emission Trans- mission Electron Microscopy Field Emission JEM-2200FS. FTIR spectra were 0925-8388/$ – see front matter © 2012 Elsevier B.V. All rights reserved. doi:10.1016/j.jallcom.2011.12.135