On-chip light sheet illumination enables diagnostic size and concentration measurements of membrane vesicles in biofluids

Cell-derived membrane vesicles that are released in biofluids, like blood or saliva, are emerging as potential non-invasive biomarkers for diseases, such as cancer. Techniques capable of measuring the size and concentration of membrane vesicles directly in biofluids are urgently needed. Fluorescence single particle tracking microscopy has the potential of doing exactly that by labelling the membrane vesicles with a fluorescent label and analysing their Brownian motion in the biofluid

Photographs of the microfluidic chips with planar waveguide for light sheet illumination in a microchannel. (a) Image of a silicon wafer with 20 planar waveguides and microchannels made from SU-8 after photolithography. (b) Light microscopy image of a microfluidic chip showing the 100 mm wide microchannel. (c) Image of a micro-fluidic chip with a glass substrate on top of a PDMS block. (d) Image of a microfluidic chip with a silicon substrate covered with a microscope cover slip.

Hendrik Deschout , Raemdonck Koen, Stremersch S, Maoddi P, Mernier G, Renaud P, Jiguet S, Hendrix A, Bracke M, Van den Broecke R, Röding M, Rudemo M, Demeester J, De Smedt SC, Strubbe F, Neyts K, Braeckmans K.

Nanoscale, 2014, 6, 1741-1747, Date: 2014