Introducing the Tellurophene-Appended BODIPY: PDT Agent with Mass Cytometry Tracking Capabilities

• Published in: ACS medicinal chemistry letters Vol. 12; no. 12; pp. 1925 - 1931
• Main Authors: Campbell, Jacob W, Tung, Matthew T, Diaz-Rodriguez, Roberto M, Robertson, Katherine N, Beharry, Andrew A, Thompson, Alison
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 09.12.2021
• Subjects: Letter; singlet oxygen; dual mass cytometry and PDT; Suzuki-coupled tellurophene
• ISSN: 1948-5875; 1948-5875
• DOI: 10.1021/acsmedchemlett.1c00492

The synthesis and characterization of the first BODIPY appended to the five-membered heterocylic tellurophene [Te] moiety is reported. By incorporating tellurophene at the meso position, the tellurophene-appended boron-dipyrromethene dye (BODIPY) acts as a multimodal agent, becoming a potent photosensitizer with a mass cytometry tag. To synthesize the compound, we developed a method to enable late-stage Suzuki–Miyaura coupling by preparing and isolating tellurophene-2-BPin in a one-step procedure from the parent tellurophene. Coupling to a meso-substituted BODIPY functionalized with a pendant aryl bromide provides the desired tellurophene-appended BODIPY. This compound demonstrated a singlet oxygen quantum yield of 0.26 ± 0.01 and produced a light dose-dependent cytotoxicity with nanomolar IC50 values against 2D cultured HeLa cells and high efficacy against 3D cultured HeLa tumor spheroids, proving to be a strong photosensitizer. The presence of the tellurophene moiety could be detected using mass cytometry, thus showcasing the ability of a tellurophene-appended BODIPY as a novel photodynamic-therapy–mass-cytometry theranostic agent.