Label-free Imaging

Phase Focus Ltd is pleased to report on a paper* describing its patented technology based on ptychography: "Ptychography - a label free, high-contrast imaging technique for live cells using quantitative phase information”   This open access paper was written by a team of scientists from the Imaging and Cytometry Laboratory, part of the Bioscience Technology Facility in the Department of Biology at the University of York

Lead authors Joanne Marrison and Laboratory Head Peter O'Toole summarised the motivation behind the studies: "Cell imaging often relies on synthetic or genetic fluorescent labels, to provide contrast which can be far from ideal for imaging cells in their in vivo state. We report on the biological application of a label-free, high contrast microscopy technique known as ptychography, in which the image producing step is transferred from the microscope lens to a high-speed phase retrieval algorithm. We demonstrate that this technology is appropriate for label-free imaging of adherent cells and is particularly suitable for reporting cellular changes such as mitosis, apoptosis and cell differentiation. The high contrast, artefact-free, focus-free information rich images allow dividing cells to be distinguished from non-dividing cells by a greater than two-fold increase in cell contrast, and we demonstrate this technique is suitable for downstream automated cell segmentation and analysis."

The authors concluded that as tychography removes the need for use of cytotoxic labels it offered high potential particularly for cancer research and drug discovery. “It addresses many of the fundamental problems inherent in current microscopy techniques. Put simply, what you get is far more than what you see. Artefacts of sample preparation which may arise from labelling or use of markers are negated,” said Peter O’Toole.

 Published in Nature Scientific Reports