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Multimodal convertible programmable superballs: Novel class of photodynamic therapeutics

By 26th November 2019January 29th, 2020No Comments

The following study was conducted by Scientists from National University of Singapore, Singapore; National Cancer Centre Singapore, Singapore.

Scientists developed programmable superballs that has unique ability for upconversion ranging from infrared light to UV / visible light for purpose of deep tissue photoactivation during the process of photodynamic therapy.  Study is published in Nature Communications as detailed below.

Nature Communications 10, Article number: 4586 (2019).

Upconversion superballs for programmable photoactivation of therapeutics


Upconversion nanoparticles (UCNPs) are the preferred choice for deep-tissue photoactivation, owing to their unique capability of converting deep tissue-penetrating near-infrared light to UV/visible light for photoactivation. Programmed photoactivation of multiple molecules is critical for controlling many biological processes. However, syntheses of such UCNPs require epitaxial growth of multiple shells on the core nanocrystals and are highly complex/time-consuming. To overcome this bottleneck, we have modularly assembled two distinct UCNPs which can individually be excited by 980/808 nm light, but not both. These orthogonal photoactivable UCNPs superballs are used for programmed photoactivation of multiple therapeutic processes for enhanced efficacy. These include sequential activation of endosomal escape through photochemical-internalization for enhanced cellular uptake, followed by photocontrolled gene knockdown of superoxide dismutase-1 to increase sensitivity to reactive oxygen species and finally, photodynamic therapy under these favorable conditions. Such programmed activation translated to significantly higher therapeutic efficacy in vitro and in vivo in comparison to conventional, non-programmed activation.


Nature Communications.



Zhang, Z., Jayakumar, M.K.G., Zheng, X. et al. Upconversion superballs for programmable photoactivation of therapeutics. Nat Commun 10, 4586 (2019) doi:10.1038/s41467-019-12506-w