Quantitative Microscopy and Tomography of Live Cells

Overview
Contrast-agent-free microscopy is highly desirable to study the dynamics and physiological activity of various structures in living cells. Most commonly, endogenous contrast can be generated from refractive index (elastic Rayleigh scattering), absorption and Raman scattering. Absorption contrast is commonly utilized in microscopy, providing structure information such as cell nuclear size and shape of with exogenous labeling. Without labeling, near-UV light can be used to distinguish between nucleic acids and proteins. Raman scattering is highly specific to the molecular structure and has been used to identify chemicals as a spectroscopy method for more than half a decade, but as an imaging method it has been slow.
The most commonly used contrast mechanism is optical phase. Its use in biological imaging of cells has a rich and long history dating back to Zernike’s invention of phase-contrast microscopy, for which he won the 1953 Nobel Prize. Since its inception, this instrument and its related techniques have been a cornerstone of every cell biology laboratory. In spite of their enormous value, phase contrast methods are inherently qualitative and lack specificity. Recent developments have focused on obtaining quantitative phase information through the use of digital imaging devices such as CCD cameras. The Laser Biomedical Research Center (LBRC) is actively developing novel quantitative phase imaging techniques with unprecedented precision and sensitivity. We believe these instruments, that allow cellular imaging without fixation and staining, will find wide commercial and scientific use in industry and university research laboratories worldwide.
Following is the list of ongoing core and collaborative interferometry-based projects:
Core Projects

• Quantitative Phase Microscopy
        - Low coherence diffraction phase microscopy
        - Wide-field dispersion phase microscopy
        - Line-field reflection phase microscopy
        - Wide-field reflection phase microscopy

• Quantitative 3-D Imaging
        - Tomographic phase microscopy
        - Synthetic aperture tomography
        - Reflection tomographic phase microscopy

Collaborative Projects:

• Refractive index maps and membrane dynamics of human red blood cells
• Cellular growth cycle study using cell dry mass
• Non-invasive monitoring of drug effect on multiple myeloma cells
• Efficient light delivery for photodynamic therapy

Other Key Biological Studies:

• Metabolic remodeling of human red blood cell membrane
• Non-invasive monitoring of membrane potential in live cells

1. Park YK, Popescu G, Badizadegan K, Dasari RR, Feld MS. Diffraction phase and fluorescence microscopy. Optics Express 14, 8263-8 (2006) PMID: 19529201.
2. Popescu G, Ikeda T, Goda K, Best-Popescu CA, Laposata M, Manley S, Dasari RR, Badizadegan K, Feld MS. Optical measurement of cell membrane tension. Physical Review Letters. 97,  (2006) PMID: 17155774.
3. Popescu G, Park YK, Dasari RR, Badizadegan K, and Feld MS. Coherence properties of red blood cell membrane motions. Physical Review E 76, 031902 (2007) PMID: 17930266.
4. Fang-Yen C, Chu MC, Seung HS, Dasari RR, and Feld MS. Phase-referenced probe interferometer for biological surface profiling and displacement measurements. Review of Scientific Instruments 78, 123703 (2007) PMID: 18163733.
5. Lue N, Choi W, Popescu G, Ikeda T, Dasari RR, Badizadegan K, Feld MS. Quantitative phase imaging of live cells using fast Fourier phase microscopy. Applied optics. 46, 1836-42 (2007).
6. Choi W, Fang-Yen C, Badizadegan K, Oh S, Lue N, Dasari RR, Feld MS. Tomographic phase microscopy. Nature methods. 4, 717-9 (2007) PMID: 17694065.
7. Lue N, Choi W, Badizadegan K, Dasari RR, Feld MS and Popescu G. Confocal diffraction phase microscopy of live cells. Optics Letters 33, 2074-2076 (2008) PMCID: PMC2730468.
8. Choi W, Yu C-C, Fang-Yen C, Badizadegan K, Dasari RR and Feld MS. Field-based angle-resolved light scattering study of single live cells. Optics Letters 33, 1596-1598 (2008) PMCID: PMC2833213.
9. Park YK, Diez-Silva M, Popescu G, Lykotrafitis G, Choi WS, Feld MS, Suresh S. Refractive index maps and membrane dynamics of human red blood cells parasitized by Plasmodium falciparum. Proceedings of the National Academy of Sciences of the United States of America. 105, 13730-5 (2008) PMCID: PMC2529332.
10. Lue N, Choi W, Popescu G, Badizadegan K, Dasari RR, Feld MS. Synthetic aperture tomographic phase microscopy for 3D imaging of live cells in translational motion. Optics Express. 16, 16240-6 (2008) PMCID: PMC2750801.
11. Yaqoob Z, Choi W, Oh S, Lue N, Park Y, Fang-Yen C, Dasari RR, Badizadegan K, Feld MS. Improved phase sensitivity in spectral domain phase microscopy using line-field illumination and self phase-referencing. Optics Express. 17, 10681-7 (2009) PMCID: PMC2844447.
12. Lue N, Choi W, Popescu G, Yaqoob Z, Badizadegan K, Dasari RR, and Feld MS. Live Cell Refractometry Using Hilbert Phase Microscopy and Confocal Reflectance Microscopy. The Journal of Physical Chemistry A 113, 13327-13330 (2009) PMCID: PMC2858636.
13. Sung Y, Choi W, Fang-Yen C, Badizadegan K, Dasari RR, Feld MS. Optical diffraction tomography for high resolution live cell imaging. Opt Express. 17, 266-77 (2009) PMCID: PMC2832333.
14. Park YK, Choi W, Yaqoob Z, Dasari RR, Badizadegan K, and Feld MS. Speckle-field digital holographic microscopy. Optics Express 17, 12285-12292 (2009) PMCID2862625.
15. Park YK, Yamauchi T, Choi W, Dasari RR, and Feld MS. Spectroscopic phase microscopy for quantifying hemoglobin concentrations in intact red blood cells. Optics Letters 34, 3668-3670 (2009) PMCID: PMC2848941.
16. Khaykovich B, Kozlova N, Choi W, Lomakin A, Hossain C, Sung Y, Dasari RR, Feld MS, Benedek GB. Thickness–radius relationship and spring constants of cholesterol helical ribbons. Proceedings of the National Academy of Sciences. 106, 15663 (2009) PMCID: PMC2747176.
17. Fu D, Choi W, Sung Y, Oh S, Yaqoob Z, Park YK, Dasari RR, and Feld MS. Ultraviolet refractometry using field-based light scattering spectroscopy. Optics Express 17, 18878-18886 (2009) PMCID: PMC2852178.
18. Park Y, Best CA, Badizadegan K, Dasari RR, Feld MS, Kuriabova T, Henle ML, Levine AJ, Popescu G. Measurement of red blood cell mechanics during morphological changes. Proceedings of the National Academy of Sciences of the United States of America. 107, 6731-6 (2010) PMCID: PMC2872375.
19. Park YK, Best CA, Auth T, Gov NS, Safran SA, Popescu G, Suresh S, Feld MS. Metabolic remodeling of the human red blood cell membrane. Proceedings of the National Academy of Sciences. 107, 1289 PMCID: PMC2802590.
20. Fu D, Oh S, Choi W, Yamauchi T, Dorn A, Yaqoob Z, Dasari RR, and Feld MS. Quantitative DIC microscopy using an off-axis self-interference approach. Optics Letters 35, 2370-2372 (2010) PMID: 20634833.
21. Fu D, Choi W, Sung Y, Yaqoob Z, Dasari RR, and Feld MS. Quantitative dispersion microscopy. Biomedical Optics Express 1, 347-353 (2010).
22. Park YK, Diez-Silva M, Fu D, Popescu G, Choi W, Barman I, Suresh S, and Feld MS. Static and dynamic light scattering of healthy and malaria-parasite invaded red blood cells. Journal of Biomedical Optics 15, 020506 (2010) PMCID: PMC2862053.