Examination of cucurbit[7]uril and its host-guest complexes by diffusion nuclear magnetic resonance

N.J. Wheate, P.G.A. Kumar, A.M. Torres, J.R. Aldrich-Wright, W.S. Price

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

The self-diffusion of cucurbit[7]uril (CB[7]) and its host−guest complexes in D2O has been examined using pulsed gradient spin−echo nuclear magnetic resonance spectroscopy. CB[7] diffuses freely at a concentration of 2 mM with a diffusion coefficient (D) of 3.07 × 10-10 m2 s-1. At saturation (3.7 mM), CB[7] diffuses more slowly (D = 2.82 × 10-10 m2 s-1) indicating that it partially self-associates. At concentrations between 2 and 200 mM, CsCl has no effect on the diffusion coefficient of CB[7] (1 mM). Conversely, CB[7] (2 mM) significantly affects the diffusion of 133Cs+ (1 mM), decreasing its diffusion coefficient from 1.86 to 0.83 × 10-9 m2 s-1. Similar changes in the rate of diffusion of other alkali earth metal cations are observed upon the addition of CB[7]. The diffusion coefficient of 23Na+ changes from 1.26 to 0.90 × 10-9 m2 s-1 and 7Li+ changes from 3.40 to 3.07 × 10-9 m2 s-1. In most cases, encapsulation of a variety of inorganic and organic guests within CB[7] decreases their rates of diffusion in D2O. For instance, the diffusion coefficient of the dinuclear platinum complex trans-[{PtCl(NH3)2}2μ-dpzm]2+ (where dpzm is 4,4'-dipyrazolylmethane) decreases from 4.88 to 2.95 × 10-10 m2 s-1 upon encapsulation with an equimolar concentration of CB[7].
LanguageEnglish
Pages2311-2314
Number of pages3
JournalJournal of Physical Chemistry B
Volume112
Issue number8
DOIs
Publication statusPublished - 2008

Fingerprint

diffusion coefficient
examination
Nuclear magnetic resonance
nuclear magnetic resonance
magnetic resonance spectroscopy
Encapsulation
alkalies
echoes
platinum
cucurbit(7)uril
saturation
cations
gradients
Alkalies
Platinum
Nuclear magnetic resonance spectroscopy
Cations
metals
Positive ions
Metals

Keywords

  • diffusion
  • nuclear magnetic resonance
  • biomedical sciences

Cite this

Wheate, N. J., Kumar, P. G. A., Torres, A. M., Aldrich-Wright, J. R., & Price, W. S. (2008). Examination of cucurbit[7]uril and its host-guest complexes by diffusion nuclear magnetic resonance. Journal of Physical Chemistry B, 112(8), 2311-2314. https://doi.org/10.1021/jp709847p
Wheate, N.J. ; Kumar, P.G.A. ; Torres, A.M. ; Aldrich-Wright, J.R. ; Price, W.S. / Examination of cucurbit[7]uril and its host-guest complexes by diffusion nuclear magnetic resonance. In: Journal of Physical Chemistry B. 2008 ; Vol. 112, No. 8. pp. 2311-2314.
@article{8775ec0073054c789225fe990c9e2721,
title = "Examination of cucurbit[7]uril and its host-guest complexes by diffusion nuclear magnetic resonance",
abstract = "The self-diffusion of cucurbit[7]uril (CB[7]) and its host−guest complexes in D2O has been examined using pulsed gradient spin−echo nuclear magnetic resonance spectroscopy. CB[7] diffuses freely at a concentration of 2 mM with a diffusion coefficient (D) of 3.07 × 10-10 m2 s-1. At saturation (3.7 mM), CB[7] diffuses more slowly (D = 2.82 × 10-10 m2 s-1) indicating that it partially self-associates. At concentrations between 2 and 200 mM, CsCl has no effect on the diffusion coefficient of CB[7] (1 mM). Conversely, CB[7] (2 mM) significantly affects the diffusion of 133Cs+ (1 mM), decreasing its diffusion coefficient from 1.86 to 0.83 × 10-9 m2 s-1. Similar changes in the rate of diffusion of other alkali earth metal cations are observed upon the addition of CB[7]. The diffusion coefficient of 23Na+ changes from 1.26 to 0.90 × 10-9 m2 s-1 and 7Li+ changes from 3.40 to 3.07 × 10-9 m2 s-1. In most cases, encapsulation of a variety of inorganic and organic guests within CB[7] decreases their rates of diffusion in D2O. For instance, the diffusion coefficient of the dinuclear platinum complex trans-[{PtCl(NH3)2}2μ-dpzm]2+ (where dpzm is 4,4'-dipyrazolylmethane) decreases from 4.88 to 2.95 × 10-10 m2 s-1 upon encapsulation with an equimolar concentration of CB[7].",
keywords = "diffusion, nuclear magnetic resonance, biomedical sciences",
author = "N.J. Wheate and P.G.A. Kumar and A.M. Torres and J.R. Aldrich-Wright and W.S. Price",
year = "2008",
doi = "10.1021/jp709847p",
language = "English",
volume = "112",
pages = "2311--2314",
journal = "Journal of Physical Chemistry B",
issn = "1520-6106",
publisher = "American Chemical Society",
number = "8",

}

Wheate, NJ, Kumar, PGA, Torres, AM, Aldrich-Wright, JR & Price, WS 2008, 'Examination of cucurbit[7]uril and its host-guest complexes by diffusion nuclear magnetic resonance' Journal of Physical Chemistry B, vol. 112, no. 8, pp. 2311-2314. https://doi.org/10.1021/jp709847p

Examination of cucurbit[7]uril and its host-guest complexes by diffusion nuclear magnetic resonance. / Wheate, N.J.; Kumar, P.G.A.; Torres, A.M.; Aldrich-Wright, J.R.; Price, W.S.

In: Journal of Physical Chemistry B, Vol. 112, No. 8, 2008, p. 2311-2314.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Examination of cucurbit[7]uril and its host-guest complexes by diffusion nuclear magnetic resonance

AU - Wheate, N.J.

AU - Kumar, P.G.A.

AU - Torres, A.M.

AU - Aldrich-Wright, J.R.

AU - Price, W.S.

PY - 2008

Y1 - 2008

N2 - The self-diffusion of cucurbit[7]uril (CB[7]) and its host−guest complexes in D2O has been examined using pulsed gradient spin−echo nuclear magnetic resonance spectroscopy. CB[7] diffuses freely at a concentration of 2 mM with a diffusion coefficient (D) of 3.07 × 10-10 m2 s-1. At saturation (3.7 mM), CB[7] diffuses more slowly (D = 2.82 × 10-10 m2 s-1) indicating that it partially self-associates. At concentrations between 2 and 200 mM, CsCl has no effect on the diffusion coefficient of CB[7] (1 mM). Conversely, CB[7] (2 mM) significantly affects the diffusion of 133Cs+ (1 mM), decreasing its diffusion coefficient from 1.86 to 0.83 × 10-9 m2 s-1. Similar changes in the rate of diffusion of other alkali earth metal cations are observed upon the addition of CB[7]. The diffusion coefficient of 23Na+ changes from 1.26 to 0.90 × 10-9 m2 s-1 and 7Li+ changes from 3.40 to 3.07 × 10-9 m2 s-1. In most cases, encapsulation of a variety of inorganic and organic guests within CB[7] decreases their rates of diffusion in D2O. For instance, the diffusion coefficient of the dinuclear platinum complex trans-[{PtCl(NH3)2}2μ-dpzm]2+ (where dpzm is 4,4'-dipyrazolylmethane) decreases from 4.88 to 2.95 × 10-10 m2 s-1 upon encapsulation with an equimolar concentration of CB[7].

AB - The self-diffusion of cucurbit[7]uril (CB[7]) and its host−guest complexes in D2O has been examined using pulsed gradient spin−echo nuclear magnetic resonance spectroscopy. CB[7] diffuses freely at a concentration of 2 mM with a diffusion coefficient (D) of 3.07 × 10-10 m2 s-1. At saturation (3.7 mM), CB[7] diffuses more slowly (D = 2.82 × 10-10 m2 s-1) indicating that it partially self-associates. At concentrations between 2 and 200 mM, CsCl has no effect on the diffusion coefficient of CB[7] (1 mM). Conversely, CB[7] (2 mM) significantly affects the diffusion of 133Cs+ (1 mM), decreasing its diffusion coefficient from 1.86 to 0.83 × 10-9 m2 s-1. Similar changes in the rate of diffusion of other alkali earth metal cations are observed upon the addition of CB[7]. The diffusion coefficient of 23Na+ changes from 1.26 to 0.90 × 10-9 m2 s-1 and 7Li+ changes from 3.40 to 3.07 × 10-9 m2 s-1. In most cases, encapsulation of a variety of inorganic and organic guests within CB[7] decreases their rates of diffusion in D2O. For instance, the diffusion coefficient of the dinuclear platinum complex trans-[{PtCl(NH3)2}2μ-dpzm]2+ (where dpzm is 4,4'-dipyrazolylmethane) decreases from 4.88 to 2.95 × 10-10 m2 s-1 upon encapsulation with an equimolar concentration of CB[7].

KW - diffusion

KW - nuclear magnetic resonance

KW - biomedical sciences

UR - http://dx.doi.org/10.1021/jp709847p

U2 - 10.1021/jp709847p

DO - 10.1021/jp709847p

M3 - Article

VL - 112

SP - 2311

EP - 2314

JO - Journal of Physical Chemistry B

T2 - Journal of Physical Chemistry B

JF - Journal of Physical Chemistry B

SN - 1520-6106

IS - 8

ER -