EPR Oximetry Sensor-Developing a TAM Derivative for In Vivo Studies
Agnieszka Boś-Liedke1,2, Magdalena Walawender3, Anna Woźniak3
1NanoBioMedical Centre, Adam Mickiewicz University, ul. Umultowska 85, 61614, Poznań, Poland. agnbos@amu.edu.pl.
Cell Biochemistry and Biophysics
|September 6, 2017
Summary
A new multimodal contrast agent, tris(2,3,5,6-tetrachloro-4-carboxy-phenyl)methyl (PTMTC), shows promise for preclinical studies. This agent is non-toxic and suitable for both electron paramagnetic resonance (EPR) and fluorescence imaging, aiding in hypoxia research.
Area of Science:
- Biomedical Imaging
- Chemical Biology
- Medical Physics
Background:
- Oxygenation is a critical physiological parameter, with hypoxia significantly impacting disease states like cancer and treatment outcomes.
- Triaryl methyl (TAM) derivative radicals are established multimodal imaging agents, utilized in electron paramagnetic resonance (EPR), magnetic resonance imaging (MRI), and fluorescence imaging.
- Hypoxia in tumors poses a therapeutic challenge, necessitating advanced imaging techniques for accurate assessment and monitoring.
Purpose of the Study:
- To characterize the multimodal properties of a novel TAM radical, tris(2,3,5,6-tetrachloro-4-carboxy-phenyl)methyl (PTMTC).
- To evaluate PTMTC's sensitivity to oxygen, spectral characteristics, stability, and toxicity for potential use as an EPR/fluorescence contrast agent.
- To assess PTMTC's suitability for preclinical applications, particularly in the context of hypoxia research.
Main Methods:
- Spectral analysis using Electron Paramagnetic Resonance (EPR) and fluorescence spectroscopy.
- In vitro cytotoxicity assays on HT-29 and FaDu cancer cell lines.
- Stability studies in various biological solutions and in vivo toxicity tests in mice.
- Assessment of oxygen sensitivity and quantum yield in a physiologically relevant buffer.
Main Results:
- PTMTC exhibits confirmed multimodal (EPR/fluorescence) properties.
- The radical demonstrated stability in various biological media and was found to be non-toxic in vitro and in vivo up to 250 mg/kg body weight.
- PTMTC showed no cellular absorption and did not interfere with standard biological assays, indicating good biocompatibility.
Conclusions:
- PTMTC is a highly promising, non-toxic multimodal contrast agent for preclinical imaging.
- Its stability and biocompatibility make it suitable for intravenous and intraperitoneal administration.
- PTMTC offers potential for advanced hypoxia detection and therapeutic monitoring in preclinical studies.
