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Human Serum Albumin Labelled with Sterically-Hindered Nitroxides as Potential MRI Contrast Agents.

ABSTRACT: Four albumin-nitroxide conjugates were prepared and tested as metal-free organic radical contrast agents (ORCAs) for magnetic resonance imaging (MRI). Each human serum albumin (HSA) carrier bears multiple nitroxides conjugated via homocysteine thiolactones. These molecular conjugates retain important physical and biological properties of their HSA component, and the resistance of their nitroxide groups to bioreduction was retained or enhanced. The relaxivities are similar for these four conjugates and are much greater than those of their individual components: the HSA or the small nitroxide molecules. This new family of conjugates has excellent prospects for optimization as ORCAs.

SUBMITTER: Dobrynin S

PROVIDER: S-EPMC7180620 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Human Serum Albumin Labelled with Sterically-Hindered Nitroxides as Potential MRI Contrast Agents.

Dobrynin Sergey S Kutseikin Sergei S Morozov Denis D Krumkacheva Olesya O Spitsyna Anna A Gatilov Yurii Y Silnikov Vladimir V Angelovski Goran G Bowman Michael K MK Kirilyuk Igor I Chubarov Alexey A

Molecules (Basel, Switzerland) 20200408 7

Four albumin-nitroxide conjugates were prepared and tested as metal-free organic radical contrast agents (ORCAs) for magnetic resonance imaging (MRI). Each human serum albumin (HSA) carrier bears multiple nitroxides conjugated via homocysteine thiolactones. These molecular conjugates retain important physical and biological properties of their HSA component, and the resistance of their nitroxide groups to bioreduction was retained or enhanced. The relaxivities are similar for these four conjugat ...[more]

PMID: 32276437

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