Physico-chemical characterization-based safety evaluation of nanocalcium

• Published in: Food and chemical toxicology Vol. 62; pp. 308 - 317
• Main Authors: Jeong, Min Sook, Cho, Hyun Sun, Park, Soo Jin, Song, Kyung Seuk, Ahn, Kyu Sup, Cho, Myung-Haing, Kim, Jun Sung
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-12-2013; Elsevier
• Subjects: Administration, Oral; Animals; atomic absorption spectrometry; Biological and medical sciences; calcium; Calcium - administration & dosage; Calcium - pharmacokinetics; Calcium - toxicity; CHO Cells - drug effects; Cricetulus; electron paramagnetic resonance spectroscopy; Electron Spin Resonance Spectroscopy; Female; Genotoxicity; Hydrogen-Ion Concentration; Male; Medical sciences; Metal Nanoparticles - administration & dosage; Metal Nanoparticles - chemistry; Metal Nanoparticles - toxicity; Mice, Inbred ICR; Microscopy, Electron, Transmission - methods; monitoring; Nanocalcium; Particle Size; Physico-chemical characteristics; rats; Rats, Sprague-Dawley; reactive oxygen species; Specific surface area; surface area; toxicity testing; Toxicity Tests - methods; Toxicity Tests, Acute - methods; Toxicology; X-radiation; X-Ray Diffraction; Specific surface area; Nanocalcium; Genotoxicity; Physico-chemical characteristics; Evaluation; Toxicity; Safety; Surface area; Physicochemical properties
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2013.08.024

•Nanocalcium is more bioavailable than microcalcium due to the large surface area.•However, there is no efficient way to evaluate nanocalcium toxicity.•Our approach contributes to the quantification of the maximum concentration of nanocalcium for further repeated toxicity test.
Nano- and microcalcium provided from the KFDA were compared in terms of physico-chemical properties. Calcium samples were tested using EF-TEM and X-ray diffractometry to check for size/morphology and crystal formation, respectively. Two samples of nano- and microcalcium were selected for further evaluation by FE-SEM, DLS (nano-size, 200–500nm; agglomerate, >5μm; micro-size, 1.5–30μm), and electron spin resonance. Both samples were heterogeneous in size, existed as single crystal and aggregated form, and did not generate reactive oxygen species. The specific surface area of nano- and microcalcium measured by N2 Brunauere Emmette Teller method was 12.90±0.27m2/g and 1.12±0.19m2/g, respectively. Inductively coupled plasma optical emission spectrometry analysis revealed the release of 2–3 times more calcium ion from nano- compared to microcalcium at pH 5 and 7. Genotoxicity and acute single-dose and repeated-dose 14-day oral toxicity testing in SD rats performed to evaluate the safety of nanocalcium did not reveal toxicity. However, long-term monitoring will be required for an unequivocal conclusion. A nanocalcium dose of 1g/kg is recommended as the maximum dose for repeated dose 13-week oral toxicity. Further studies could provide details of toxicity of nanocalcium on the repeated dose 13-week oral toxicity test.