Fan Chen, , Kecheng Li, Yanyan Jiang, Hongxu Lu, Elvis Pandzic, Sandra Fok, Alexander Macmillan, , Martina Stenzel*

University of New South Wales
Centre for Advanced Macromolecular Design (CAMD), School of Chemistry
Sydney, NSW, Australia

We report a method for imaging and identifying the release site of drugs from polyion complex (PIC) micelles in 3D tumour spheroids using a newly developed fluorescence microscopy, light-sheet microscopy. Negatively charged polymers were synthesised using RAFT polymerisation to form PIC micelles with a positively charged model drug, lysozyme (Lys). By acquiring images on light-sheet microscopy for tumour spheroids, we were able to observe the distribution of polymer and protein in tumour spheroids. We found that the protein distributed all over the spheroid after only 2 hours but polymer was only found at the periphery of cell spheroid even after an incubation of 6 hours. By looking further into single cells, we found the polymers interacted with mitochondria upon cell internalisation, causing the release of drugs. The released lysozyme was able to be transported into inner areas of a cell spheroid. 

Biographic Details
Name: Fan CHEN
Title: Mr
Affiliation, Country: Centre for Advanced Macromolecular Design (CAMD), School of Chemistry, University of New South Wales, Australia
Research interests: Drug delivery system, fluororescence microscopy