Multi-Modal Protein-Engineered Theranostic Fibers: Drug encapsulation, Imaging, and enhanced 19F MRS

Motivation: Theranostic materials allows for simultaneous therapeutic and diagnostic disease intervention. Goal(s): We aimed to engineer a protein-based theranostic with multiple imaging modalities. Approach: Using noncannonical amino acid incorporation of trifluoroleucine (TFL), we synthesize fluorinated coiled-coil, Q2TFL, imageable by 1H MRI and high-frequency ultrasound, and sensitive to 19F MRS. Results: Q2TFL demonstrates reduced signal contrast in 1H MRI, echogenic signals under high-frequency ultrasound, and enhances sensitivity in linear ratiometric 19F MRS. This allows for thermoresponsiveness and potential protein conformation analysis. Q2TFL serves as a promising platform for versatile and effective theranostic agents, bringing together therapeutic and diagnostic modalities in a compact and efficient manner. Impact: Q2TFL, a fluorinated protein fiber, enables drug delivery and offers unique multimodal imaging. It acts as a temperature probe and protein structure monitor, paving the way for innovative theranostic biomaterials.