Organic Phosphorous and Calcium Source Induce the Synthesis of Yolk-Shell Structured Microspheres of Calcium Phosphate with High-Specific Surface Area: Application in HEL Adsorption

• Published in: Nanoscale research letters Vol. 15; no. 1; p. 69
• Main Authors: Cao, Xianshuo, Wang, Guizhen, Wang, Kai, Guo, Lan, Cao, Yang, Cao, Xianying, Yang, Yong
• Format: Journal Article
• Language: English
• Published: New York Springer US 30-03-2020; Springer Nature B.V; SpringerOpen
• Subjects: Adenosine; Adsorption; ATP; Biocompatibility; Calcium; Calcium phosphate; Calcium phosphates; Chemical properties; Chemistry and Materials Science; Drug delivery; Drug delivery systems; Lactic acid; Materials Science; Microspheres; Molecular Medicine; Morphology; Nano Express; Nanochemistry; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Physicochemical properties; Shells (structural forms); Specific surface; Specific surface area; Surface area; Surface chemistry; Synthesis; Yolk; Yolk-shell; Calcium phosphate; Specific surface area; Adsorption; Yolk-shell
• ISSN: 1931-7573; 1556-276X; 1556-276X
• DOI: 10.1186/s11671-020-03298-w

Yolk-shell-structured calcium phosphate microspheres have a great potential for medical applications due to their excellent physicochemical properties and biocompatibility. However, developing a yolk-shell-structured calcium phosphate with high adsorption capability remains a challenge. Herein, a porous yolk-shell-structured microsphere (ATP-CG) of calcium phosphate with high-specific surface area [
S
BET
= 143 m
2
g
−1
, which is approximately three times as high as that of ATP-CL microspheres synthesized by replacing calcium source with calcium
l
-lactate pentahydrate (CL)] was successfully synthesized by using adenosine 5'-triphosphate disodium salt (ATP) as the phosphorous source and calcium gluconate monohydrate (CG) as calcium source through a self-templating approache. The influences of molar ratio of Ca to P (Ca/P), hydrothermal temperature, and time on the morphology of ATP-CG microspheres were also investigated. It is found that the organic calcium source and organic phosphorous source play a vital role in the formation of yolk-shell structure. Furthermore, a batch of adsorption experiments were investigated to illuminate the adsorption mechanism of two kinds of yolk-shell-structured microspheres synthesized with different calcium sources. The results show that the adsorption capacity of ATP-CG microspheres (332 ± 36 mg/g) is about twice higher than that of ATP-CL microspheres (176 ± 33 mg/g). Moreover, the higher-specific surface area caused by the calcium source and unique surface chemical properties for ATP-CG microspheres play an important role in the improvement of HEL adsorption capability. The study indicates that the as-prepared yolk-shell-structured microsphere is promising for application in drug delivery fields and provides an effective approach for improving drug adsorption capability.