Nanoanalytical Electron Microscopy Reveals a Sequential Mineralization Process Involving Carbonate-Containing Amorphous Precursors

File Description SizeFormat 
NitiputriK-ACSNano-2016-accepted-version.docxAccepted version9.81 MBMicrosoft WordView/Open
Title: Nanoanalytical Electron Microscopy Reveals a Sequential Mineralization Process Involving Carbonate-Containing Amorphous Precursors
Authors: Nitiputri, K
Ramasse, QM
Autefage, H
McGilvery, CM
Boonrungsiman, S
Evans, ND
Stevens, MM
Porter, AE
Item Type: Journal Article
Abstract: A direct observation and an in-depth characterization of the steps by which bone mineral nucleates and grows in the extracellular matrix during the earliest stages of maturation, using relevant biomineralization models as they grow into mature bone mineral, is an important research goal. To better understand the process of bone mineralization in the extracellular matrix, we used nanoanalytical electron microscopy techniques to examine an in vitro model of bone formation. This study demonstrates the presence of three dominant CaP structures in the mineralizing osteoblast cultures: <80 nm dense granules with a low calcium to phosphate ratio (Ca/P) and crystalline domains; calcium phosphate needles emanating from a focus: “needle-like globules” (100–300 nm in diameter) and mature mineral, both with statistically higher Ca/P compared to that of the dense granules. Many of the submicron granules and globules were interspersed around fibrillar structures containing nitrogen, which are most likely the signature of the organic phase. With high spatial resolution electron energy loss spectroscopy (EELS) mapping, spatially resolved maps were acquired showing the distribution of carbonate within each mineral structure. The carbonate was located in the middle of the granules, which suggested the nucleation of the younger mineral starts with a carbonate-containing precursor and that this precursor may act as seed for growth into larger, submicron-sized, needle-like globules of hydroxyapatite with a different stoichiometry. Application of analytical electron microscopy has important implications in deciphering both how normal bone forms and in understanding pathological mineralization.
Issue Date: 6-Jul-2016
Date of Acceptance: 6-Jul-2016
ISSN: 1936-086X
Publisher: American Chemical Society
Start Page: 6826
End Page: 6835
Journal / Book Title: ACS Nano
Volume: 10
Issue: 7
Copyright Statement: This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Nano, © 2016 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see
Sponsor/Funder: Commission of the European Communities
Funder's Grant Number: ERC-2013-CoG-616417
Keywords: Nanoscience & Nanotechnology
MD Multidisciplinary
Publication Status: Published
Appears in Collections:Faculty of Engineering
Faculty of Natural Sciences

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Creative Commons