Abstract
The development of metal-free magnetic resonance imaging (MRI) agents demands precise control over molecular architecture to achieve optimal performance. Current fluorine-based contrast agents rely on maximizing fluorine content (>20 wt %) for sensitivity, requiring extensive solubilizing groups that lead to signal-diminishing aggregation. Here we show that discrete brush polymers (Đ = 1.0) with precise backbone lengths and a single terminal fluorine group achieve superior imaging performance through architectural control rather than high fluorine content. This design prevents both intra- and intermolecular fluorine aggregation while maintaining high aqueous solubility, enabling sharper signals and higher sensitivity than conventional systems despite containing less than 7 wt % fluorine. Systematic investigation reveals how backbone length controls fluorine mobility and signal generation, establishing clear structure-property relationships previously obscured by molecular heterogeneity. This work demonstrates how precise architectural control can enhance functional performance beyond traditional approaches, providing new strategies for designing imaging materials.
| Original language | English |
|---|---|
| Journal | Journal of the American Chemical Society |
| DOIs | |
| State | Accepted/In press - 2025 |
| Externally published | Yes |
Funding
N.O. and J.L. acknowledge the support from the National Institute of General Medical Sciences of the National Institutes of Health (R35GM151217) and the National Science Foundation CAREER Award (2340664). S.J. acknowledges the support from the National Cancer Institute of the National Institutes of Health (R01CA255176). The authors acknowledge the support for material characterizations by the NMR, Shared Laboratory for Macro and Bio-Macromolecular Research, and Shared Instrumentation Facilities at Louisiana State University. The authors acknowledge the technical support from Japan Analytical Industry (JAI). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or the National Science Foundation.