title: Tracking Drug Loading Capacities of Calcium Silicate Hydrate Carrier: A Comparative X-ray Absorption Near Edge Structures Study.
abstract: Mesoporous spheres of calcium silicate hydrate (MS-CSH) have been prepared by an ultrasonic method. Following an earlier work in which we have revealed the interactions between ibuprofen (IBU) and CSH carriers with different morphologies by X-ray absorption near edge structures (XANES) analysis. In the present investigation, two new drug molecules, alendronate sodium (ALN) and gentamicin sulfate (GS), were incorporated into MS-CSH, and their drug loading capacities (DLCs) were measured using thermogravimetric analysis to establish the relationship between drug-carrier interactions and DLCs. The XANES spectra clearly indicate that acidic functional groups of the drug molecules linked to the active sites (Ca-OH and Si-OH groups) of MS-CSH on the surface by electrostatic interactions. In addition, it is found that the stoichiometric ratio of Ca(2+) ions of CSH carriers and the functional groups of drug molecules may significantly influence the DLCs.
authors.affiliation: †Department of Chemistry, University of Western Ontario, London, Ontario N6A 5B7, Canada.
authors.forename: Xiaoxuan
authors.initials: X
authors.lastname: Guo
authors.affiliation: †Department of Chemistry, University of Western Ontario, London, Ontario N6A 5B7, Canada.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: ‡Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Wu
authors.affiliation: †Department of Chemistry, University of Western Ontario, London, Ontario N6A 5B7, Canada.
authors.forename: Yun-Mui
authors.initials: YM
authors.lastname: Yiu
authors.affiliation: §Canadian Light Source, Saskatoon, Saskatchewan S7N 2V3, Canada.
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Hu
authors.affiliation: ‡Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.
authors.forename: Ying-Jie
authors.initials: YJ
authors.lastname: Zhu
authors.affiliation: †Department of Chemistry, University of Western Ontario, London, Ontario N6A 5B7, Canada.
authors.forename: Tsun-Kong
authors.initials: TK
authors.lastname: Sham
mesh_terms: D019386:Alendronate / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry; D005839:Gentamicins / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D010316:Particle Size; D017640:Silicates / Q000737:chemistry*; D013499:Surface Properties; D013818:Thermogravimetry; D014867:Water / Q000737:chemistry*; D056928:X-Ray Absorption Spectroscopy
chemical_list: D017610:Calcium Compounds; D004337:Drug Carriers; D005839:Gentamicins; D017640:Silicates; D014867:Water; C031293:calcium silicate; D019386:Alendronate