Drug Carriers Based on Zirconium Phosphate Nanoparticles

Magnetic Reson in Chemistry

Contreras-Ramírez

Drake

et al. 2022

Solid‐state NMR experiments on 2H, 31P, 13C, and 1H nuclei, including 31P T1, 1H T1, and 1H T1ρ measurements, as well as on the kinetics of proton‐phosphorus cross‐polarization have been performed to characterize the crystalline and amorphous α‐zirconium phosphates, which were intercalated with D2O and/or CD3OD. The 13C{1H} CP MAS NMR experiment performed for compound 1‐CD3OD (Zr (HPO4)2.0.2CD3OD) with carbon cross‐polarization via protons of phosphate groups has provided a prove that the methanol was intercalated into the interlayer spaces of this compound. The variable‐temperature 2H solid‐echo MAS NMR spectra of intercalated compounds demonstrated that the methanol molecules, in contrast to the mobile water, were immobile, keeping, however, free CD3 rotations around the C3‐axis. It has been demonstrated that the intercalated species, D2O and CD3OD, do not affect the high‐frequency motions of the phosphate groups. By utilizing local structural models that satisfy the constraints of the experimental data, it has been suggested that the immobile methanol molecules are located in the cavity between two neighboring layers of the zirconium phosphates. Thus, the present work illustrates the reliable criteria in a comprehensive NMR approach to structural and dynamic studies of such systems.

Section: Introductionmentioning

confidence: 99%

Elucidating structure and dynamics of crystalline α‐zirconium phosphates intercalated with water and methanol by multinuclear solid‐state MAS NMR: A comprehensive NMR approach

Magnetic Reson in Chemistry

Contreras-Ramírez

Drake

et al. 2022

“…For example, α ‐zirconium phosphate ( α ‐ZrP) of formula Zr(HPO 4 ) 2 •H 2 O, itself, has a small interlayer distance of 7.6 Å, which limits its applications. However, by intercalating organic compounds, such as amines, quaternary ammonium ions, or biomolecules, the interlayer distance can be increased to allow uptake of different cationic complexes, pillaring agents and many others including creation of molecular systems used for drug delivery . The applications can be significantly improved by a special design of the zirconium phosphate surface with specific organic/inorganic groups …”

Section: Introductionmentioning

confidence: 99%

Modification and intercalation of layered zirconium phosphates: a solid‐state NMR monitoring

Magnetic Reson in Chemistry

Kan

Sheikh

et al. 2017

Self Cite

Several layered zirconium phosphates treated with Zr(IV) ions, modified by monomethoxy-polyethyleneglycol-monophosphate and intercalated with doxorubicin hydrochloride have been studied by solid-state MAS NMR techniques. The organic components of the phosphates have been characterized by the C{ H} CP MAS NMR spectra compared with those of initial compounds. The multinuclear NMR monitoring has provided to establish structure and covalent attachment of organic/inorganic moieties to the surface and interlayer spaces of the phosphates. The MAS NMR experiments including kinetics of proton-phosphorus cross polarization have resulted in an unusual structure of zirconium phosphate 6 combining decoration of the phosphate surface by polymer units and their partial intercalation into the interlayer space. Copyright © 2016 John Wiley & Sons, Ltd.

“…For example, α-ZrP phosphate can be potentially intercalated with an anticancer drug and its surface can be treated with Zr(IV) ions to place a metal anchor for surface modification without altering the interlayer space used for drug loading, and modified with polyethylene glycol units to provide biocompatibility. During the past years, many efforts have been dedicated to the intercalation of different anticancer drugs to develop potential drug nanocarriers to target cancer cells …”

Section: Introductionmentioning

confidence: 99%

³¹P NMR Relaxation and Motions of Phosphate Groups in Layered Zirconium Phosphate Materials

Clearfield

2016

J. Phys. Chem. C

There is little systematic understanding of the motions of phosphate groups in layered zirconium phosphate (α-ZrP) materials applied in chemistry, industry, and nanomedicine for drug delivery. In this paper, we show how to quantitatively characterize correlation times of motions in the zirconium phosphate network on the basis of NMR 31 P relaxation time measurements. By studies of α-ZrP phosphates and their intercalated and decorated derivatives, we have established that room-temperature 31 P relaxation is governed by rotations of HPO 4 − groups with correlation times of (1.1− 4.7) × 10 −8 s restricted by H-bonding with water molecules in ordered and locally disordered areas. The disordered areas have been found by the 1 H spin-lock proton−phosphorus cross-polarization 31 P{ 1 H} MAS NMR experiments.