Red blood cell three-dimensional morphometry by quantitative phase microscopy

In humans, healthy mature erythrocytes or Red Blood Cells (RBCs) have globule structure and mostly important they lack a cell nucleus and most organelles, thus RBC is an envelope filled of uniform and transparent liquid. Abnormal RBCs may be fragmented or shaped like teardrops, crescents, needles, or a variety of other forms deviating from their regular ordinary shape. Here we show that seeing an erythrocyte-ensemble as nanolens-array, detection of abnormal cells can be made rapidly and efficiently without recurring to subjective shape analysis of image by the doctor or by sophisticated image processing tools, but rather by exploiting their abnormal shape alterations affecting the lens-focusing properties. Demonstration of how aberrations affect the focusing properties of the RBC is given by Hartmann- Shack approach and Zernike polynomial-fitting, as occurs for wavefront aberration correction in adaptive modern astronomic telescopes. The results show how the concept of biological lens could be addressed for revolutionary integration between photonics and biology and that a fast blood pre-screening can be performed by the proposed approach.