Special Issue "Biomimetic Growth of Calcium Phosphate Crystals"

A special issue of Crystals (ISSN 2073-4352). This special issue belongs to the section "Crystalline Materials".

Deadline for manuscript submissions: closed (1 December 2018)

Special Issue Editors

Guest Editor
Dr. Michele Iafisco

Laboratory of Bioceramics and Bio-hybrid Composites, CNR - Institute of Science and Technology for Ceramics. Via Granarolo, 64 I-48018 FAENZA (RA), Italy
Website | E-Mail
Interests: biomaterials, biomineralization, nanomedicine, calcium phosphates, bioceramics
Guest Editor
Dr. José Manuel Delgado-López

Instituto Andaluz de Ciencias de la Tierra (IACT, CSIC-UGR), Armilla, Granada, Spain
E-Mail
Interests: biomineralization; crystallography; SAXS-WAXS-AFM; bioinspired materials; drug delivery

Special Issue Information

Dear Colleagues,

Understanding how living organisms form their extremely specialized mineralized structures, and identifying the organic molecules controlling the final crystal size, shape and polymorphism, which in turn determine their unique mechanical properties, is highly relevant, not only on the fundamental knowledge side, but also as a source of inspiration for the design of advanced biomaterials. In fact, bio-inspiration is currently among the most exciting concepts ruling advancements in materials science, medicine and other smart technological applications. Synthetic calcium phosphates are among the most interesting and versatile biomimetic materials since they chemically resemble the inorganic phase in hard tissues (e.g., bone, dentine, fish scales, horns of different animals) and pathological calcifications (e.g., dental and urinary calculi, tendon mineralization, calcification of blood vessels). Most of their excellent features, including biocompatibility and bioactivity, can be significantly enhanced by improving their biomimetism, that is, by mimicking the size, morphology, (nano)structure and chemical composition of the biological counterparts. Therefore, the synthesis of calcium phosphates under physiological conditions (so-called “biomimetic”) or mediated by organic additives, resembling the small molecules or macromolecules of the organic matrix of bone and teeth, is a matter of intensive research and a hot topic.

In this Special Issue, we welcome orginal research and review articles covering the state of the art and the lastest results on the synthesis of biomimetic calcium phosphates aiming to either providing a better understading of the mechanisms underlying mineral formation in living organims or designing novel biomaterials with higher level of performance and new functionalities.

Dr. Michele Iafisco
Dr. José Manuel Delgado-López
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Crystals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Calcium phosphate
  • Biomineralization
  • Biomaterials
  • Nanomedicine

Published Papers (3 papers)

View options order results:
result details:
Displaying articles 1-3
Export citation of selected articles as:

Research

Open AccessArticle Habit Change of Monoclinic Hydroxyapatite Crystals Growing from Aqueous Solution in the Presence of Citrate Ions: The Role of 2D Epitaxy
Crystals 2018, 8(8), 308; https://doi.org/10.3390/cryst8080308
Received: 9 July 2018 / Revised: 25 July 2018 / Accepted: 25 July 2018 / Published: 27 July 2018
PDF Full-text (1762 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Calcium hydroxyapatite (HAp) has been crystallized from aqueous solutions in the presence of citrate ions, in two temperature intervals. At lower temperature, where citrate could form the stable 3D-ordered phase Ca-citrate-tetrahydrate (Ca-Cit-TH), only the monoclinic (P21/c) HAp polymorph occurs
[...] Read more.
Calcium hydroxyapatite (HAp) has been crystallized from aqueous solutions in the presence of citrate ions, in two temperature intervals. At lower temperature, where citrate could form the stable 3D-ordered phase Ca-citrate-tetrahydrate (Ca-Cit-TH), only the monoclinic (P21/c) HAp polymorph occurs and assumes the shape of fence-like aggregates, built by sharply [010] elongated lamellae dominated by the pinacoid {001}. This pronounced anisotropic growth habit is compared with the usually considered rod-like pseudo-hexagonal occurring in pure aqueous solution growth. The habit change is interpreted by assuming that 2D islands of Ca-citrate-tetrahydrate can be adsorbed as epi- monolayers of thickness d001 onto the different growth forms: {001}, {100}, {102¯}, {010}, and {101¯} of HAp. A comparison is made among the corresponding coincidence lattices, in order to explain on reticular basis the selective adsorption of citrate on the {001} HAp form. The role exerted by the 2D-epitaxially adsorbed Ca-Cit-TH as a “mortar” in the monoclinic HAp “brick” assembly is outlined as well. Full article
(This article belongs to the Special Issue Biomimetic Growth of Calcium Phosphate Crystals)
Figures

Figure 1

Open AccessArticle Amorphous Calcium Phosphate Formation and Aggregation Process Revealed by Light Scattering Techniques
Crystals 2018, 8(6), 254; https://doi.org/10.3390/cryst8060254
Received: 30 May 2018 / Revised: 8 June 2018 / Accepted: 15 June 2018 / Published: 17 June 2018
PDF Full-text (2485 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Amorphous calcium phosphate (ACP) attracts attention as a precursor of crystalline calcium phosphates (CaPs) formation in vitro and in vivo as well as due to its excellent biological properties. Its formation can be considered to be an aggregation process. Although aggregation of ACP
[...] Read more.
Amorphous calcium phosphate (ACP) attracts attention as a precursor of crystalline calcium phosphates (CaPs) formation in vitro and in vivo as well as due to its excellent biological properties. Its formation can be considered to be an aggregation process. Although aggregation of ACP is of interest for both gaining a fundamental understanding of biominerals formation and in the synthesis of novel materials, it has still not been investigated in detail. In this work, the ACP aggregation was followed by two widely applied techniques suitable for following nanoparticles aggregation in general: dynamic light scattering (DLS) and laser diffraction (LD). In addition, the ACP formation was followed by potentiometric measurements and formed precipitates were characterized by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), and atomic force microscopy (AFM). The results showed that aggregation of ACP particles is a process which from the earliest stages simultaneously takes place at wide length scales, from nanometers to micrometers, leading to a highly polydisperse precipitation system, with polydispersity and vol. % of larger aggregates increasing with concentration. Obtained results provide insight into developing a way of regulating ACP and consequently CaP formation by controlling aggregation on the scale of interest. Full article
(This article belongs to the Special Issue Biomimetic Growth of Calcium Phosphate Crystals)
Figures

Graphical abstract

Open AccessArticle Effect of Calcium and Phosphate on Compositional Conversion from Dicalcium Hydrogen Phosphate Dihydrate Blocks to Octacalcium Phosphate Blocks
Crystals 2018, 8(5), 222; https://doi.org/10.3390/cryst8050222
Received: 23 April 2018 / Revised: 8 May 2018 / Accepted: 16 May 2018 / Published: 17 May 2018
Cited by 3 | PDF Full-text (6879 KB) | HTML Full-text | XML Full-text
Abstract
Octacalcium phosphate (OCP) has attracted much attention as an artificial bone substitute because of its excellent osteoconductive and bone replacement properties. Although numerous studies have investigated OCP powder fabrication, there are only a few studies on OCP block fabrication. Therefore, in this study,
[...] Read more.
Octacalcium phosphate (OCP) has attracted much attention as an artificial bone substitute because of its excellent osteoconductive and bone replacement properties. Although numerous studies have investigated OCP powder fabrication, there are only a few studies on OCP block fabrication. Therefore, in this study, the feasibility of optimizing dicalcium hydrogen phosphate dihydrate (DCPD) blocks, as a precursor for OCP block fabrication, under a pH 6 adjusted acetate buffer solution at 70 °C for 2 days was investigated. When a DCPD block was immersed in acetate buffer, the block was partially converted to OCP, with a large amount of dicalcium hydrogen phosphate anhydrate (DCPA), and its macroscopic structure was maintained. When the DCPD block was immersed in a Ca-containing solution, it was converted to mainly hydroxyapatite (HAp) with DCPA. On the other hand, when the DCPD block was immersed in a PO4-containing solution, the block was converted to OCP, and its macroscopic structure was maintained. In other words, the PO4-induced calcium phosphate with a Ca/P molar ratio lower than 1.0 may represent an intermediate phase during the compositional transformation from a DCPD block to an OCP block through the dissolution–precipitation reaction. Full article
(This article belongs to the Special Issue Biomimetic Growth of Calcium Phosphate Crystals)
Figures

Figure 1

Back to Top