To explore biology at the single cell level, we have built optical tweezers with integrated microfluidics, and fluorescence, brightfield and back focal plane interferometry detection methods.
We have developed Optical Tweezers optimised for observations of single bacterial cells stained with fluorescent dyes. The configuration consists of a holographic optical trap operating at near infra-red (NIR) wavelength integrated with microfluidics and combined with epifluorescence and bright field microscopy, and back focal plane (BFP) interferometry.
Example of a microfluidic chip
a) E. coli bacteria stained with SYTO 9 trapped in optical tweezers and imaged with epifluorescence.
b) 1.8 µm green fluorescent beads trapped in optical tweezers and imaged using epifluorescence. Position of the trap is indicated by the yellow circle.