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Gd(III)-induced Supramolecular Hydrogelation with Enhanced Magnetic Resonance Performance for Enzyme Detection.

ABSTRACT: Here we report a supramolecular hydrogel based on Gd(III)-peptide complexes with dramatically enhanced magnetic resonance (MR) performance. The hydrogelations were formed by adding Gd(III) ion to the nanofiber dispersion of self-assembling peptides naphthalene-Gly-Phe-Phe-Tyr-Gly-Arg-Gly-Asp (Nap-GFFYGRGD) or naphthalene-Gly-Phe-Phe-Tyr-Gly-Arg-Gly-Glu (Nap-GFFYGRGE). We further showed that, by adjusting the molar ratio between Gd(III) and the corresponding peptide, the mechanical property of resulting gels could be fine-tuned. The longitudinal relaxivity (r₁) of the Nap-GFFYGRGE-Gd(III) was 58.9?mM^-1?S^-1, which to our knowledge is the highest value for such peptide-Gd(III) complexes so far. Such an enhancement of r₁ value could be applied for enzyme detection in aqueous solutions and cell lysates.

SUBMITTER: Hua Y

PROVIDER: S-EPMC5225466 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Gd(III)-induced Supramolecular Hydrogelation with Enhanced Magnetic Resonance Performance for Enzyme Detection.

Hua Yongquan Y Pu Guojuan G Ou Caiwen C Zhang Xiaoli X Wang Ling L Sun Jiangtao J Yang Zhimou Z Chen Minsheng M

Scientific reports 20170111

Here we report a supramolecular hydrogel based on Gd(III)-peptide complexes with dramatically enhanced magnetic resonance (MR) performance. The hydrogelations were formed by adding Gd(III) ion to the nanofiber dispersion of self-assembling peptides naphthalene-Gly-Phe-Phe-Tyr-Gly-Arg-Gly-Asp (Nap-GFFYGRGD) or naphthalene-Gly-Phe-Phe-Tyr-Gly-Arg-Gly-Glu (Nap-GFFYGRGE). We further showed that, by adjusting the molar ratio between Gd(III) and the corresponding peptide, the mechanical property of re ...[more]

PMID: 28074904

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