Spin diffusion transfer difference (SDTD) NMR: An advanced method for the characterisation of water structuration within particle networks

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:594

Article

Gabrielli, Valeria¹  Kuraite, Agne¹  da Silva, Marcelo Alves²  Edler, Karen J.²  Angulo, Jesus^1,3  Nepravishta, Ridvan^1,4  Munoz-Garcia, Juan C.¹  Khimyak, Yaroslav Z.¹ 

[1] Univ East Anglia, Sch Pharm, Norwich Res Pk, Norwich NR4 7TJ, Norfolk, England

[2] Univ Bath, Dept Chem, Bath BA2 7AY, Avon, England

[3] Univ Seville, Dept Chem, Prof Garcia Gonzalez St, Seville 41012, Spain

[4] Univ Texas Med Branch, Dept Biochem & Mol Biol, Galveston, TX 77555 USA

关键词: Spin diffusion;    Saturation transfer difference NMR;    Hydrogel;    Solvation properties;   

DOI  :  10.1016/j.jcis.2021.02.094

来源: Elsevier

【 摘 要 】

Hypothesis: The classical STD NMR protocol to monitor solvent interactions in gels is strongly dependent on gelator and solvent concentrations and does not report on the degree of structuration of the solvent at the particle/solvent interface. We hypothesised that, for suspensions of large gelator particles, solvent structuration could be characterised by STD NMR when taking into account the particle-to-solvent H-1-H-1 spin diffusion transfer using the 1D diffusion equation. Experiments: We have carried out a systematic study on effect of gelator and solvent concentrations, and gelator surface charge, affecting the behaviour of the classical STD NMR build-up curves. To do so, we have characterised solvent interactions in dispersions of starch and cellulose-like particles prepared in deuterated water and alcohol/D2O mixtures. Findings: The Spin Diffusion Transfer Difference (SDTD) NMR protocol is independent of the gelator and solvent concentrations, hence allowing the estimation of the degree of solvent structuration within different particle networks. In addition, the simulation of SDTD build-up curves using the general one-dimensional diffusion equation allows the determination of minimum distances (r) and spin diffusion rates (D) at the particle/solvent interface. This novel NMR protocol can be readily extended to characterise the solvent(s) organisation in any type of colloidal systems constituted by large particles. (C) 2021 Published by Elsevier Inc.

【 授权许可】

Free