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bioRxiv · 10.1101/2020.09.02.274969

Triplet-Triplet Annihilation PLGA-Nanoparticles for Cancer Bioimaging

Vepris, O.·Eich, C.·Feng, Y.·Zhang, H.·Kaijzel, E. L.·Cruz, L. J.
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Abstract

Triplet-triplet annihilation upconversion (TTA-UC) nanoparticles (NPs) have emerged as imaging probes and therapeutic probes in recent years due to their excellent optical properties. In contrast to lanthanide ions-doped inorganic materials, highly efficient TTA-UC can be generated by low excitation power density, which makes it suitable for clinical applications. In the present study, we used biodegradable poly(lactic-co-glycolic acid) (PLGA)-NPs as delivery vehicle for TTA-UC based on the heavy metal porphyrin Platinum(II) octaethylporphyrin (PtOEP) and the polycyclic aromatic hydrocarbon 9,10-diphenylanthracene (DPA) as photosensitizer/emitter pair. TTA-UC-PLGA-NPs were successfully synthesized according to an oil-in-water emulsion and solvent evaporation method. After physicochemical characterization, UC-efficacy of TTA-UC-PLGA-NPs was assessed in vitro and ex vivo. TTA-UC could be detected in the tumor area 96 hours after in vivo administration of TTA-UC-PLGA-NPs, confirming the integrity and suitability of PLGA-NPs as TTA-UC in vivo delivery system. Thus, this study provides proof-of-concept that the advantageous properties of PLGA can be combined with the unique optical properties of TTA-UC for the development of advanced nanocarriers for simultaneous in vivo molecular imaging and drug delivery.

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Vepris, O., Eich, C., Feng, Y., Zhang, H., Kaijzel, E. L., Cruz, L. J.. 2020-09-03. Triplet-Triplet Annihilation PLGA-Nanoparticles for Cancer Bioimaging. https://doi.org/10.1101/2020.09.02.274969

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