The Mechanical Consequences of the Interplay of Mineral Distribution and Organic Matrix Orientation in the Claws of the Sea Slater Ligia pallasii

Exposed regions of the arthropod exoskeleton have specialized structure and mineral composition. Their study can provide insights into the evolutionary optimization of the cuticle as a material. We determined the structural and compositional features of claws in the crustacean Ligia pallasii using X-ray micro-computed tomography, scanning electron microscopy (SEM), and analytical scanning transmission electron microscopy (STEM). In addition, we used nanoindentation to determine how these features fine-tune the mechanical properties of the claw cuticle. We found that the inner layer of the claw cuticle—the endocuticle—contains amorphous calcium phosphate, while the outer layer—the exocuticle—is not mineralized and contains elevated amounts of bromine. While the chitin–protein fibers in crustacean exoskeletons generally shift their orientation, they are aligned axially in the claws of L. pallasii. As a consequence, the claw cuticle has larger elastic modulus and hardness in the axial direction. We show that amorphous calcium phosphate mineralization and the brominated cuticle are widespread in isopod crustaceans inhabiting terrestrial habitats. We discuss how the features of the claw cuticle may aid in minimizing the likelihood of fracture. Ultimately, our study points out the features that increase the durability of thin skeletal elements.

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Evaluation of the remineralization potential of amorphous calcium phosphate and fluoride containing pit and fissure sealants using scanning electron microscopy

Indian Journal of Dental Research ◽

10.4103/0970-9290.100419 ◽

2012 ◽

Vol 23 (2) ◽

pp. 157 ◽

Cited By ~ 5

Author(s):

Prashant Choudhary ◽

M Ganesh ◽

Shobha Tandon ◽

Anshul Mehra

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Calcium Phosphate ◽

Amorphous Calcium Phosphate ◽

Fissure Sealants ◽

Pit And Fissure Sealants ◽

Scanning Electron

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Ultrasonic application and spray drying during amorphous calcium phosphate synthesis

Letters in Applied NanoBioScience ◽

10.33263/lianbs84.711714 ◽

2019 ◽

Vol 8 (4) ◽

pp. 711-714

Keyword(s):

Electron Microscopy ◽

Particle Size ◽

Calcium Phosphate ◽

Spray Drying ◽

Amorphous Calcium Phosphate ◽

Calcium Phosphates ◽

Calcium Content ◽

Synthesis Process ◽

Particle Sizes ◽

Ultrasound Application

Hydroxyapatite, amorphous calcium phosphates, calcium triphosphate and calcium octaphosphate are the main components present in bones and teeth. Calcium phosphates are easily synthesized, playing an important role in regenerative medicine, being able to be used as bone implants. There are different ways of synthesizing phosphates, the most commonly used being wet chemical method. The objective of this work was to study the influence of the use of ultrasound and spray drying on the synthesis of amorphous calcium phosphate. Two synthetic variants were studied. One without ultrasound application and the other with ultrasound application. The samples obtained were characterized by X-ray diffraction, FTIR spectroscopy and scanning electron microscopy. The particle size by electron microscopy and the calcium content by atomic absorption was determined. The results showed that when spray drying is applied, particle sizes of less than 261 nm are obtained in the samples synthesized without ultrasound application, being less than 59 nm in the samples synthesized with ultrasound application. The statistical analysis by ANOVA showed significant differences between the particle sizes of the samples synthesized without ultrasound application and the samples synthesized by applying ultrasound. In both cases the particles were spherical. The results obtained show that the application of ultrasound during the synthesis process decreases the particle size, increasing the surface area, which favors the spray drying process.

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Interplay of organic matrix and amorphous calcium phosphate strengthens the isopod claw

European Microscopy Congress 2016: Proceedings ◽

10.1002/9783527808465.emc2016.6001 ◽

2016 ◽

pp. 199-200

Author(s):

Miloš Vittori ◽

Vesna Srot ◽

Birgit Bussmann ◽

Peter A. van Aken ◽

Jasna Štrus

Keyword(s):

Calcium Phosphate ◽

Amorphous Calcium Phosphate ◽

Organic Matrix

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A Comparative Study of Pathological Nanomineral Aggregates with Distinct Morphology in Human Aortic Atherosclerotic Plaques

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.18449 ◽

2021 ◽

Vol 21 (1) ◽

pp. 547-554

Author(s):

Yuan Li ◽

Changqiu Wang ◽

Anhuai Lu ◽

Kang Li ◽

Xiao Cheng ◽

...

Keyword(s):

Electron Microscopy ◽

Calcium Phosphate ◽

Amorphous Calcium Phosphate ◽

Microscopic Analysis ◽

Atherosclerotic Plaques ◽

Carbonate Hydroxyapatite ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Precursor Phase ◽

Exact Difference

Calcification exists in atherosclerotic plaques in the form of nanomineral aggregates and is closely related to the development of atherosclerosis. Spheroidal and massive calcification are two major types of calcification found in atherosclerotic tissue. However, the exact difference between these two types of calcification is still not clear. Samples composed entirely of spheroidal calcifications and massive calcifications were isolated from aortic atherosclerotic plaques and tested using both bulk and microscopic analysis techniques. Scanning electron microscopy and transmission electron microscopy showed that spheroidal calcifications had a core–shell structure. Massive calcifications were composed of randomly arranged nanocrystals. Synchrotron radiation X-ray diffraction, Raman spectroscopy and selected area electron diffraction showed amorphous calcium phosphate, whitlockite and carbonate hydroxyapatite all existing in spheroidal calcification, while massive calcification only consisted of carbonate hydroxyapatite. We conclude that amorphous calcium phosphate may act as a precursor phase of spheroidal calcifications that eventually transforms into a crystalline phase, while whitlockite in lesions could aggravate the progression of atherosclerosis.

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Remineralization of enamel subsurface lesions with casein phosphopeptide-amorphous calcium phosphate: A quantitative energy dispersive X-ray analysis using scanning electron microscopy: An in vitro study

Journal of Conservative Dentistry ◽

10.4103/0972-0707.92609 ◽

2012 ◽

Vol 15 (1) ◽

pp. 61 ◽

Cited By ~ 14

Author(s):

MithraN Hegde ◽

Anu Moany

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Calcium Phosphate ◽

Amorphous Calcium Phosphate ◽

In Vitro Study ◽

Energy Dispersive ◽

X Ray ◽

Casein Phosphopeptide ◽

Scanning Electron

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Phase Transformation Mechanism of Amorphous Calcium Phosphate to Hydroxyapatite Investigated by Liquid-Cell Transmission Electron Microscopy

Crystal Growth & Design ◽

10.1021/acs.cgd.1c00503 ◽

2021 ◽

Author(s):

Biao Jin ◽

Zhaoming Liu ◽

Changyu Shao ◽

Jiajun Chen ◽

Lili Liu ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Phase Transformation ◽

Calcium Phosphate ◽

Amorphous Calcium Phosphate ◽

Transformation Mechanism ◽

Transmission Electron ◽

Cell Transmission ◽

Liquid Cell

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Recent studies of the mineral phase in bone and its possible linkage to the organic matrix by protein-bound phosphate bonds

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1984.0041 ◽

1984 ◽

Vol 304 (1121) ◽

pp. 479-508 ◽

Cited By ~ 259

Keyword(s):

Calcium Phosphate ◽

Bone Mineral ◽

Amorphous Calcium Phosphate ◽

Solid Phase ◽

Function Analysis ◽

Bone Matrix ◽

Organic Matrix ◽

X Ray Diffraction ◽

X Ray ◽

Mineralized Tissues

The most widely accepted hypothesis to account for maturational changes in the X-ray diffraction characteristics of bone mineral has been the ‘amorphous calcium phosphate theory’, which postulates that an initial amorphous calcium phosphate solid phase is deposited that gradually converts to poorly crystalline hydroxyapatite. Our studies of bone mineral of different ages by X-ray radial distribution function analysis and 31 P n.m.r. have conclusively demonstrated that a solid phase of amorphous calcium phosphate does not exist in bone in any significant amount. 31 P n.m.r. studies have detected the presence of acid phosphate groups in a brushite-like configuration. Phosphoproteins containing O -phosphoserine and O -phosphothreonine have been isolated from bone matrix and characterized. Tissue and cell culture have established that they are synthesized in bone, most likely by the osteoblasts. Physicochemical and pathophysiological studies support the thesis that the mineral and organic phases of bone and other vertebrate mineralized tissues are linked by the phosphomonester bonds of O -phosphoserine and O -phosphothreonine, which are constituents of both the structural organic matrix and the inorganic calcium phosphate crystals.

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Ossification Vesicles with Calcium Phosphate in the Eyes of the InsectCopium teucrii(Hemiptera: Tingidae)

The Scientific World JOURNAL ◽

10.1100/tsw.2011.9 ◽

2011 ◽

Vol 11 ◽

pp. 186-198 ◽

Cited By ~ 9

Author(s):

Javier Garcia-Guinea ◽

Alberto Jorge ◽

Laura Tormo ◽

Marta Furio ◽

Elena Crespo-Feo ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Chemical Composition ◽

Calcium Phosphate ◽

Laser Scanning Microscopy ◽

Bone Collagen ◽

Pigment Cells ◽

Confocal Laser ◽

Phosphate Mineralization ◽

Scanning Electron

Arthropod eyes are built of repeating units named ommatidia. Each single ommatidium unit contains a cluster of photoreceptor cells surrounded by support cells and pigment cells. The insectCopiumeye ommatidia include additional calcium-phosphate deposits, not described in insects to date, which can be examined today using a combined set of modern microscopy and spectroscopy techniques.Teucrium gnaphalodesL'Her plants, growing in central Spain, develop galls induced byCopiuminsects. A survey ofC. teucriiadult specimens resulted in surprising environmental scanning electron microscopy (ESEM) images, showing that their bright red eyes contain a calcium-phosphate mineralization. A complete survey ofCopiumeye specimens was performed by ESEM using energy-dispersive spectroscopy, backscattered electron detector and cathodoluminescence (CL) probes, field emission scanning electron microscopy, micro-Raman spectroscopy, and confocal laser scanning microscopy in order to learn ommatidia features, such as chemical composition, molecular structure, cell membrane, and internal ommatidium eye fluids and calcium-phosphate distribution deposits. The CL panchromatic images distinguish between the calcium-phosphate ommatidium and calcium-phosphate setae, which are more apatite rich. They show Raman bands attributable to bone tissue apatite biomaterials, such as bone, collagen, lipids, and blood, i.e., peptides, amide-S, amide-II, amide-III, and cytochrome P-450scc. The chemical composition of both galls and leaves ofT. gnaphalodeswas determined by gas chromatography – mass spectrometry (GC-MS) of their extracts. The spectrometric and microscopic images reveal that the calcium-phosphate mineralization is formed and constrained toCopiumommatidia, which are both matrix vesicles generating mixtures of apatite collagen and operational compound eyes of the insect.

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