- Synthesis, structure, and EPR characterization of deuterated derivatives of Finland trityl radical
-
Substituted trityl radicals are important spin probes for functional electron paramagnetic resonance spectroscopy and imaging including oxygen and pH mapping in vivo. Here we report the synthetic procedure for large scale synthesis of deuterated Finland t
- Dhimitruka, Ilirian,Grigorieva, Olga,Zweier, Jay L.,Khramtsov, Valery V.
-
-
Read Online
- Synthesis, Characterization, and Nanoencapsulation of Tetrathiatriarylmethyl and Tetrachlorotriarylmethyl (Trityl) Radical Derivativesí-A Study to Advance Their Applicability as in Vivo EPR Oxygen Sensors
-
Tissue oxygenation plays an important role in the pathophysiology of various diseases and is often a marker of prognosis and therapeutic response. EPR (ESR) is a suitable noninvasive oximetry technique. However, to reliably deploy soluble EPR probes as oxygen sensors in complex biological systems, there is still a need to investigate and improve their specificity, sensitivity, and stability. We reproducibly synthesized various derivatives of tetrathiatriarylmethyl and tetrachlorotriarylmethyl (trityl) radicals. Hydrophilic radicals were investigated in aqueous solution mimicking physiological conditions by, e.g., variation of viscosity and ionic strength. Their specificity was satisfactory, but the oxygen sensitivity was low. To enhance the capability of trityl radicals as oxygen sensors, encapsulation into oily core nanocapsules was performed. Thus, different lipophilic triesters were prepared and characterized in oily solution employing oils typically used in drug formulations, i.e., middle-chain triglycerides and isopropyl myristate. Our screening identified the deuterated ethyl ester of D-TAM (radical 13) to be suitable. It had an extremely narrow single EPR line under anoxic conditions and excellent oxygen sensitivity. After encapsulation, it retained its oxygen responsiveness and was protected against reduction by ascorbic acid. These biocompatible and highly sensitive nanosensors offer great potential for future EPR oximetry applications in preclinical research.
- Frank, Juliane,Elewa, Marwa,M. Said, Mohamed,El Shihawy, Hosam A.,El-Sadek, Mohamed,Müller, Diana,Meister, Annette,Hause, Gerd,Drescher, Simon,Metz, Hendrik,Imming, Peter,M?der, Karsten
-
p. 6754 - 6766
(2015/10/06)
-