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.

Mesoporous Calcium-Silicate Nanoparticles Loaded with Low-Dose Triton-100+Ag+ to Achieve Both Enhanced Antibacterial Properties and Low Cytotoxicity for Dentin Disinfection of Human Teeth

“…The results of FTIR revealed that M-AgTX preserved the specific adsorption peak of benzene skeleton and silicon skeleton structure, suggesting the incorporation of TX-100 within M-AgTX [ 28 , 30 , 31 ]. Although the chemical mechanism behind this combination is still undetermined, the active sites of Ca-OH and Si-OH groups of MCSNs and −CH 2 groups of TX-100 could very much likely bind together through a covalent binding process under a heated-stirring condition [ 13 , 32 ]. When considering the EDS and pH curve, the Ca 2+ cations on the surface of M-AgTX might serve as the inherent active site to effectively adsorb TX-100 with -OH groups [ 17 ].…”

XANES spectroscopy for the clinician

“…The first concerns metabolic disorders that can be studied by experiments at the K edge of metals (here, Fe) [69]. The second involves drugs developed for different purposes, namely cancer and infection, and characterizes the speciation of both light (C) and heavy (Ag and Pt) elements [147,148]. The third shows how Kedge XANES (Zn) can provide valuable clinical information about patients developing skin reactions to tattooing.…”

Biodegradable Inorganic Nanostructured Biomaterials for Drug Delivery

“…Guo et al. [ 148,149 ] used calcium and silicon K‐edge XANES to investigate the interactions between drug molecules and CSH and anhydrous calcium silicate nanocarriers with different morphologies. Significant changes were observed in XANES spectra after IBU drug loading, revealing the ordering of silicates locally and loss of hydrates during the IBU loading process.…”

“…The acidic drug molecules could be loaded into CSH nanocarriers easily with high drug loading capacities, but surface modification of CSH nanocarriers such as acidic groups could load basic drug molecules into CSH nanocarriers with high drug loading capacities. [ 149 ] They also prepared different CSH/polymer nanocomposites and used XANES to analyze effects of polymer intercalation in CSH nanocarriers on drug loading capacity and drug release kinetics. It was found that polymers could alter the structure of CSH to various degrees which could influence the drug loading capacity and drug release kinetics.…”