Red blood cell as an adaptive optofluidic microlens

Abstract

The perspective of using live cells as lenses could open new revolutionary and intriguing scenarios in the future of biophotonics and biomedical sciences for endoscopic vision, local laser treatments via optical fibres and diagnostics. Here we show that a suspended red blood cell (RBC) behaves as an adaptive liquid-lens at microscale, thus demonstrating its imaging capability and tunable focal length. In fact, thanks to the intrinsic elastic properties, the RBC can swell up from disk volume of 90 fl up to a sphere reaching 150 fl, varying focal length from negative to positive values. These live optofluidic lenses can be fully controlled by triggering the liquid buffer's chemistry. Real-time accurate measurement of tunable focus capability of RBCs is reported through dynamic wavefront characterization, showing agreement with numerical modelling. Moreover, in analogy to adaptive optics testing, blood diagnosis is demonstrated by screening abnormal cells through focal-spot analysis applied to an RBC ensemble as a microlens array.

Red blood cell three-dimensional morphometry by quantitative phase microscopy

“…The latter permits to retrieve the wavefront aberrations induced on a plane wave that passes through the RBC [17]. In particular, we calculate the focusing plane of the diffracted wavefront, demonstrating that for discocyte RBC, i.e.…”

Full 3D morphology of diatoms flowing in a microfluidic channel by digital holographic microscopy

“…It has proved to be very powerful and accurate if applied to convex objects, such as sperm cells, but failed for objects presenting concavities. Successively, the method has been implemented and extended to a wider set of objects, also with concavities, such as red blood cells [7], [8]. The method is all-optical and non-invasive, being based on the combination of optical tweezers (OT) and digital holographic set-ups [10], [11].…”

Biological elements carry out optical tasks in coherent imaging systems

“…[3][4][5][6][7] Imaging through complex media, hologram denoising, and resolution enhancement are among the most investigated issues in DH. [8][9][10][11][12][13][14][15][16] The capabilities offered by DH microscopy turns out to be particularly useful for LoC studies.…”