TY - JOUR
T1 - Hypermineralized whale rostrum as the exemplar for bone mineral
AU - Li, Zhen
AU - Pasteris, Jill D.
AU - Novack, Deborah
N1 - Funding Information:
The work is partially funded by NIH grant 1R21AR055184-01A2. The histological sectioning and staining were carried out by Crystal Idleburg in Washington University Musculoskeletal Research Center, Award Number P30AR057235 from the National Institute of Arthritis, Musculoskeletal, and Skin
PY - 2013
Y1 - 2013
N2 - Although bone is a nanocomposite of mineral and collagen, mineral has been the more elusive component of study. A standard for bone mineral is clearly needed. We hypothesized that the most natural, least-processed bone mineral could be retrieved from the most highly mineralized bone. We therefore studied the rostrum of the toothed whale Mesoplodon densirostris, which has the densest recognized bone. Essential to establishment of a standard for bone mineral is the documentation that the proposed tissue is bone-like in all properties except for its remarkably high concentration of mineral. Transmitted-light microscopy of unstained sections of rostral material shows normal bone morphology in osteon geometry, lacunae concentration, and vasculature development. Stained sections reveal extremely low density of thin collagen fibers in most of the bone, but enrichment of thicker collagen fibers around vascular holes and in a minority of osteons. Field-emission scanning electron microscopy shows the rostrum mostly consists of dense mineral prisms. Most rostral areas have the same chemical-structural features, i.e., Raman spectroscopically dominated by strong bands at ∼962 Δcm-1 and weak bands at ∼2940 Δcm-1. Spectral features indicate that the rostrum is composed mainly of the calcium phosphate mineral apatite and has only about 4 wt.% organic content. The degree of carbonate substitution (∼8.5 wt.% carbonate) in the apatite is in the upper range found in most types of bone. We conclude that, despite its enamel-like extraordinarily high degree of mineralization, the rostrum is in all other features bone-like. Its mineral component is the long-sought uncontaminated, unaltered exemplar of bone mineral.
AB - Although bone is a nanocomposite of mineral and collagen, mineral has been the more elusive component of study. A standard for bone mineral is clearly needed. We hypothesized that the most natural, least-processed bone mineral could be retrieved from the most highly mineralized bone. We therefore studied the rostrum of the toothed whale Mesoplodon densirostris, which has the densest recognized bone. Essential to establishment of a standard for bone mineral is the documentation that the proposed tissue is bone-like in all properties except for its remarkably high concentration of mineral. Transmitted-light microscopy of unstained sections of rostral material shows normal bone morphology in osteon geometry, lacunae concentration, and vasculature development. Stained sections reveal extremely low density of thin collagen fibers in most of the bone, but enrichment of thicker collagen fibers around vascular holes and in a minority of osteons. Field-emission scanning electron microscopy shows the rostrum mostly consists of dense mineral prisms. Most rostral areas have the same chemical-structural features, i.e., Raman spectroscopically dominated by strong bands at ∼962 Δcm-1 and weak bands at ∼2940 Δcm-1. Spectral features indicate that the rostrum is composed mainly of the calcium phosphate mineral apatite and has only about 4 wt.% organic content. The degree of carbonate substitution (∼8.5 wt.% carbonate) in the apatite is in the upper range found in most types of bone. We conclude that, despite its enamel-like extraordinarily high degree of mineralization, the rostrum is in all other features bone-like. Its mineral component is the long-sought uncontaminated, unaltered exemplar of bone mineral.
KW - Apatite
KW - Bone mineral
KW - Histology
KW - Raman spectroscopy
KW - Rostrum
KW - Scanning electron microscopy
UR - http://www.scopus.com/inward/record.url?scp=84877292459&partnerID=8YFLogxK
U2 - 10.3109/03008207.2013.769973
DO - 10.3109/03008207.2013.769973
M3 - Article
C2 - 23586370
AN - SCOPUS:84877292459
VL - 54
SP - 167
EP - 175
JO - Connective Tissue Research
JF - Connective Tissue Research
SN - 0300-8207
IS - 3
ER -