Amino Acid-Derived Sensors for Specific Zn²⁺ Detection Using Hyperpolarized ¹³ C Magnetic Resonance Spectroscopy

Alterations in Zn²⁺ concentration are seen in normal tissues and in disease states, and for this reason imaging of Zn²⁺ is an area of active investigation. Herein, enriched [1-¹³ C]cysteine and [1-¹³ C₂ ]iminodiacetic acid were developed as Zn²⁺ -specific imaging probes using hyperpolarized ¹³ C magnetic resonance spectroscopy. [1-¹³ C]cysteine was used to accurately quantify Zn²⁺ in complex biological mixtures. These sensors can be employed to detect Zn²⁺ via imaging mechanisms including changes in ¹³ C chemical shift, resonance linewidth, or T₁ .