Targeted theranostics : near-infrared triterpenoic acid-rhodamine conjugates as prerequisites for precise cancer diagnosis and therapy

Abstract

Pentacyclic triterpenoic acids have shown excellent potential as starting materials for the synthesis of highly cytotoxic agents with significantly reduced toxicity for non-malignant cells. This study focuses on the development of triterpenoic acid-rhodamine conjugates with fluorescence shifted to the near-infrared (NIR) region for theranostic applications in cancer research. Spectral analysis revealed emission wavelengths around λ = 760 nm, enabling stronger signals and deeper tissue penetration. The conjugates were evaluated using SRB assays on tumor cell lines and non-malignant fibroblasts, demonstrating low nanomolar activity and high selectivity, similarly to their known rhodamine B counterparts. Additional staining experiments proved their mode of action as mitocans.